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The purpose of Part A of this document is to seek comments on proposals for the following:
This document will also set in Part B out the position of Health Canada on the following health claims that have been approved for use in the United States:
A diet-related health claim is a statement that links a food or constituent of a food to reducing the risk of developing a diet-related disease or condition (e.g., osteoporosis, cancer) in the context of the total diet. The composition of a food that carries the claim must contribute to a dietary pattern associated with the claimed benefit.
In November 1998, Health Canada announced its policy regarding health claims for foods in the Policy Paper on Nutraceuticals/Functional Foods and Health Claims on Foods. The policy stated that risk reduction and structure/function claims should be permitted for foods while all other products claiming to cure, treat, mitigate or prevent illness should continue to be regulated as drugs. The policy was the result of a two-year consultation with all interested stakeholders.
Two key steps were undertaken to implement the policy. The first was the development of standards of evidence to evaluate foods with health claims. This resulted in the publication of the Interim Guidance Document on Preparing a Submission for Foods with Health Claims-Incorporating the Standards of Evidence.
As a second step in implementing this policy, Health Canada in 1999 began an evaluation of the diet-disease relationships that formed the basis for the ten health claims that were authorized at that time in the U.S. under the Nutrition Labeling and Education Act of 1990. The process involved contracting with Canadian experts to prepare reports updating the science related to the ten health claims since the U.S. Food and Drug Administration had finalized its reviews (1993 for most claims). The reports were subsequently peer-reviewed. Taking these reports into consideration, Health Canada scientists undertook a systematic review to provide details necessary for setting out the conditions for each claim. The review process supported five of the ten claims with modifications (sodium, potassium and hypertension; calcium, vitamin D and osteoporosis; saturated and trans fat and heart disease; vegetables and fruit and cancer; carbohydrates that do not promote dental caries). The executive summaries of the scientific reviews along with the elements and conditions for these five claims were published for comment in 2000.
For the five remaining claims, the same peer review process was undertaken. For these however, the outcome varied. In one case the expert reviewers agreed that the updated science did not continue to support the claim (fat and cancer); in three others, they disagreed about certain aspects of the claim [the strength of the evidence behind the claim (fibre-containing grain products and cancer); the use of the term "soluble fibre" (from fruits, vegetables and grain products; from oats and psyllium)], and in the case of folate and neural tube defects, the reviewers did not address the issue of supplement recommendations versus food sources in the Canadian context. Health Canada scientists undertook systematic reviews in 4 cases to resolve the outstanding issues, but in the case of the claim pertaining to soluble fibre from oats and psyllium, no review was undertaken because this was considered a "product-specific" claim (see p 10 for further discussion of this claim). In preparing these systematic reviews, Health Canada's standards of evidence were applied to evaluate the evidence using the approach described in the Interim Guidance Document on Preparing a Submission for Foods with Health Claims. For most claims the Health Canada reviews covered the period from when the claims were accepted in the US, i.e., 1993, until the date the reviews were conducted i.e., between 2000 and 2003, depending on the claim. The delay in publishing this position paper until 2006 arose because of the complex nature of some of the implementation issues, such as characterizing the whole grain content of foods. The outcomes of the Health Canada reviews are noted below for each claim.
Statements or claims linking a food to a reduction in risk of a disease are deemed to bring the food within the definition of a drugFootnote 1 in the Food and Drugs Act. Furthermore, three of the diet-related diseases - cancer, heart disease and hypertension - are listed in Schedule A so the prohibitions contained in Subsections 3(1) and 3(2)Footnote 2 of the Act also apply. Therefore amendments to the Food and Drug Regulations are required to permit the use of health claims in food labelling and advertising.
The regulations (B.01.600 - B.01.603) providing for the use of health claims in food labelling and advertising were included in Schedule of Amendments No. 1172 on nutrition labelling and claims published in the Canada Gazette Part II on January 1, 2003. Section B.01.601Footnote 3, written under the authority of paragraph 30 (1)(j) of the Food and Drugs Act, exempts foods that are the subject of the permitted claims on labels or in advertisements from the provisions of the Act and Regulations respecting drugs and from Subsections 3 (1) and (2) of the Act. The wording of the claims is specified in quotes and follows, except where not appropriate, the two step format set out in the Codex Guidelines for Use of Nutrition and Health Claims. The first part describes the characteristics of the diet associated with the reduced risk of the disease; the second part describes the compositional aspects of the food that make it a suitable part of the diet. The claims and conditions for their use are set out in the Table following B.01.603
The Health Canada review of the U. S. health claim for fruits, vegetables and whole grain products that contain fibre and reduced risk of heart disease, particularly soluble fibre, assessed the large body of new evidence which has been published since 1993 through 2000. The executive summary of the review is attached (Annex 1). The evidence continues to support the relationship between consumption of fruit, vegetables, whole grains and brans and reduced risk of coronary heart disease. Evidence from experimental and observational prospective cohort and case control studies of acceptable quality demonstrated that risk of coronary heart disease (CHD) was reduced with increasing intakes of vegetables and fruit. An even greater number of experimental studies of acceptable quality was available on the effects of whole grains and brans on CHD risk factors in addition to a few large cohort studies. Consistency in the evidence was demonstrated in that the large majority of the experimental studies (randomized controlled trials) showed significant lipid-lowering effects with whole grains and brans. The majority of the cohort studies reported a reduction in CHD morbidity and mortality associated with consumption of whole grains and brans.
The U.S.-approved health claim relates the reduction in risk of CHD to the total fibre and soluble fibre content of the food. In Health Canada's review of more recent data, the effect of fibre intake from vegetables and fruit on CHD risk, examined in three prospective cohort studies, was found to be not significant suggesting that the effects of vegetables and fruits in reducing CHD risk is related to constituents other than fibre. In addition, in controlled studies where the effect of fruit or vegetable intake on blood lipids was investigated, the amount of fruit or vegetable (with the associated fibre content) required to affect blood lipids was much greater than the amount associated with risk reduction in the cohort studies suggesting that the effect of vegetables and fruit on CHD may be mediated through other mechanisms than their effect on blood lipids.
Experimental studies of the effects of fibre (total and soluble) from a variety of cereal grains and certain oil seeds (flax in three studies, sunflower seed in one study) have demonstrated a link between fibre intakes and reductions in blood lipids with oats and oat bran being the most effective in reducing lipid levels in hypercholesterolemic subjects. Blood lipids are biomarkers for CHD risk. Evidence for actual decreases in CHD morbidity and mortality in the healthy general population comes from prospective cohort studies which examined the relationship between the intake of whole grains and brans and CHD risk. Three independent large scale cohort studies have found a significant reduction in risk related to consumption of whole grains, including brans. Whole grains in these studies included products made with wheat and brown rice among other cereal grains. These grains are not characterized as containing soluble fibre. Based on these studies, and the fact that the risk reduction was associated with servings of whole grains, and that a limited number of studies focussed on dietary fibre per se, the scientific review concluded that fibre should not be mentioned in the claim and that a minimum level of soluble fibre should not be a criterion for the claim.
It was further concluded that brans should not be included in the health claim because the efficacy of brans is affected by processing. Until more evidence is available on the efficacy of brans under a wide range of processing effects, allowing brans to bear the claim is premature.
Since the evidence supports the link between diets containing whole grains, vegetables, and fruit and reduced risk of CHD, it is proposed that the Table following B.01.603 be amended to permit the following health claims:
1. In the case of a vegetable or fruit:
"A healthy diet rich in a variety of vegetables, fruit and whole grain products may reduce the risk of heart disease."
"A healthy diet rich in a variety of vegetables and fruit may reduce the risk of heart disease."
"A healthy diet rich in a variety of vegetables and fruit may reduce the risk of heart disease and some types of cancer."Footnote 4
Conditions for the Claims:
It is proposed that inclusion/exclusion criteria for vegetables and fruit be the same as those for the claim linking vegetable and fruit consumption with reduced risk of some cancers set out in column 2 of Item 4 in the Table following section B.01.603, viz:
The exclusions can apply to both the heart disease claim and the cancer claim because the epidemiological evidence in both cases related to the consumption of fruits and vegetables, and their juices and excluded potatoes, tofu, soybeans, and lentils as vegetables. Condiments and preserves made with fruits or vegetables similarly were not normally included as fruits and vegetables. The other white starchy roots and tubers such as cassava and yams would be excluded as being similar in composition to potatoes.
2. In the case of a whole grain product:
"A healthy diet rich in a variety of vegetables, fruit and whole grain products may reduce the risk of heart disease. (Naming the food) contains (naming the percentage) whole grain(s) / (Naming the food) contains (naming the percentage) whole (naming the grain(s))."
"A healthy diet rich in whole grain products may reduce the risk of heart disease. (Naming the food) contains (naming the percentage) whole grain(s) / (Naming the food) contains (naming the percentage) whole (naming the grain(s))."
Conditions for the Claim:
To address the issue of what constitutes a whole grain, a definition is required. It is proposed that the definition of the American Association of Cereal Chemists (AACC), 1999, be adopted and incorporated in Section B.01.001 of the Regulations to apply to "whole grain(s)", "whole cereal grain(s)" and "whole (naming the grain(s))". The definition is as follows:
Whole grains shall consist of the intact, ground, cracked or flaked caryopsis, whose principal anatomical components - the starchy endosperm, germ and bran - are present in the same relative proportions as they exist in the intact caryopsis.
The current interest in grains has resulted in seeds such as poppy seed and legumes such as soy being included in the grain count in "multi-grain" products. To ensure that only those foods which are correctly considered "grains"are included in any claim for grains, it is proposed that a definition of "grain" be included in B.01.001. Grain would be defined as the dried seeds of a list of cereal species, namely, wheat (includes all species intended for human consumption, including spelt and kamut), barley, oats, rye, corn, rice, wild rice, millet (includes all species intended for human consumption), sorghum, teff and triticale, and of pseudo-cereals, i.e. the seeds of certain dicotyledonous plants including buckwheat, amaranth, and quinoa. This list is based on recognized classification of cereal grains and pseudocereals (Plants Consumed by Man by Brouk, 1975; online searches Purdue University, Mayo Clinic, FAO). Oilseeds such as flax, sesame seeds, poppy seeds, and legumes such as soy beans are not included because they were not normally included in the studies of the relationship to heart disease risk reduction and are not considered cereal grains.
There is at present considerable interest in claiming the presence of whole grains in foods. It has been noted that the proportion of whole grain ingredients contained in products that are claimed to be made with whole grains or to be "multi-grain" may be very low. The claims could mislead the consumer into thinking that the products contained substantial amounts of whole grains. It is therefore proposed that Division 1 of the Food and Drug Regulations be amended to require that the percentage of whole grains, either in total or individually if the grains are specifically named, be declared in any statement or claim for the presence of whole grains in a food, e.g. "Contains 25% whole grains"; "Made with 15% whole oats and 10% whole wheat". The percentage would be calculated by dividing the ingoing weight of the whole grain ingredient(s) by the total weight of all the ingoing ingredients of the food, excluding the weight of added water or volatile ingredients evaporated or removed during processing, and multiplying this amount by 100. This estimation is consistent with the Canadian Food Inspection Agency Guidelines for Highlighted Ingredients and Flavours.
A whole grain bread:
55 g whole grain wheat flour
25 g other ingredients
30 g water
110 g total ingoing weight at the mixing bowl
90 g finished weight (20 g moisture lost in processing)
Percent whole grain is 55 / (110-20=90) X 100% = 61%
The issue of requiring a minimum level of whole grains, in the case of any statement respecting whole grain, was considered. It was decided from a health point of view that no minimum amount of whole grain would be required in a food in order for the food to carry an indication of its whole grain content.
|Food||Calculation of % whole grain||% Whole grain declaration|
|Bread, made with 100% whole grain wheat flour||55 g whole grain flour
25 g water
31 g other ingredients
Total ingoing weight=111 g
Finished weight =83 g ( 25% moisture loss)
% whole grain is 55 /83 x 100%=66%
|Bread, made with 60% whole grain wheat flour (40% white)||60% of 55 g is whole grain=33 g whole grain wheat flour
25 g water
53 g other ingredients
Total ingoing weight=111 g
Finished weight=83 g (25% moisture loss)
% whole grain is 33/83 x 100%=40%
|Bread, made with 100% whole wheat flour (Canadian standard whole wheat bread)
See description on page 8 regarding the composition of whole wheat flour.
|30% of 55 g is whole grain flour=16.5 g whole grain wheat flour
25 g water
69.5 g other ingredients
Total ingoing weight= 111 g
Finished weight= 83 g (25% moisture loss)
% whole grain is 16.5/83 x 100%=20%
|Rice pudding made with brown rice||71 g whole grain rice
118 g water
584 g other ingredients
Total ingoing weight= 773 g
Finished weight= 564 g (27% moisture loss)
% whole grain is 71/564 x 100%=13%
The Case of Whole Wheat Flour and Bread
The standard for whole wheat flour in the Food and Drug Regulations permits the exclusion of 5% of the wheat berryFootnote 5. This effectively means that about 70% of the germ is typically removed. As such, the flour could only be said to be 30% whole grain (see further explanation of this later in this section). Thus, flour meeting the minimum requirements of the standard for whole wheat flour does not meet the proposed definition of whole grain. At the same time, there are breads and bakery products on the market in Canada made with flour containing 100% of the wheat berry. While the flour used in these products can also be called "whole wheat flour," typically, manufacturers differentiate them by declaring the presence of the germ or using the term "whole grain" to describe the product. These currently make up a small proportion (about 15%) of the bread market. Regular whole wheat bread (about 21% of the bread market) is made from flour that is missing about 70% of the germ.
Since the names "whole wheat flour" and "(naming the percentage) whole wheat bread" are the official names of the foods meeting the respective standards in the Food and Drug Regulations, (B.13.005, B.13.026), Health Canada is concerned that consumers will not adequately recognize the difference between whole wheat flour meeting the Canadian standard and whole wheat flour that meets the definition of whole grain (and products made with them). Therefore, Health Canada is considering revising the standard for whole wheat flour to require a declaration of the % whole grain content of the flour.
A flour that is declared as100% whole grain would therefore contain 100% of the wheat berry or all three principal anatomical components in the same relative proportions as in the intact grain. Flour which contains the three components in proportions different from the intact grain would have a % whole grain declaration that reflects the lowest of the three components of the whole grain. For example, if the flour contains 100% of the bran, 100% of the endosperm and 30% of the germ of the original wheat berry, the whole grain content of the flour would be 30%.
It is proposed that the regulation for the standard for (naming the %) whole wheat bread would similarly be modified to require a declaration of the whole grain content.
The relationship between folic acid and reduced risk of neural tube defects (NTDs) is the subject of a recommendation contained in the Health Canada publication Nutrition for a Healthy Pregnancy - National Guidelines for the Childbearing Years, 1999:
"Research has found that the risk of babies having a neural tube defect is reduced when women consume a daily multivitamin/multimineral supplement containing folic acid beginning before becoming pregnant and continuing through the early weeks of pregnancy. Taking the evidence as a whole, a daily supplement containing 400 µg (0.4 mg) of folic acid together with the amount of folate found in a healthy diet is expected to reduce the risk for women who have not previously had a pregnancy affected by a neural tube defect. Although the focus has been on folic acid, it is unclear from the results of research completed to date whether folic acid alone will have the same proven beneficial effects for these women as folic acid taken as a component of a multivitamin\mineral supplement. Taking a supplement containing folic acid does not preclude the need to follow a healthy eating pattern according to Canada's Food Guide to Healthy Eating".
Although the Health Canada Scientific Summary (Executive Summary, Annex 2) concluded that the evidence continued to support the relationship between folate and NTD risk reduction, it was decided not to include a health claim on folate and NTDs with the other health claims in Schedule No. 1172 (Nutrition Labelling and Claims) for several reasons. It was not feasible to obtain 400 µg of folic acid, the synthetic form of the vitamin, from fortified foods in the Canadian diet at that time and the evidence suggested that the most complete protection was provided by the ingestion of a multivitamin/mineral supplement which would supply other nutrients such as vitamin B12 which, like folate, are also involved in methyl group metabolism.
The level of folic acid fortification of white flour and other products was increased in 1998 but not enough to permit this level of additional folic acid intake from foods. Therefore, while it was anticipated that some reduction in neural tube birth defects rates was possible, it was only predicted to be up to 20% whereas a reduction of 40% or more was considered possible based on the studies where supplements were used.
Examination of NTD rates before, during and since the introduction of mandatory addition of folic acid to white flour and enriched pasta and cornmeal, however, has shown that there has been a decrease of approximately 50% on average in the incidence of NTDs in Canada temporally associated with the introduction. This is concurrent with an increase in red blood cell folate in a large sample of Canadians such that the prevalence of folate insufficiency has dropped below 0.5%. The mean levels of red cell folate have increased from 527 nmol/L prefortification to 741 nmol/L following full adoption of fortification by industry (since approximately January 1998). This change in red cell folate concentration would correlate with a net increased intake in folic acid of approximately 115 micrograms per day. From provincial dietary survey data, the folic acid fortification of flour provides an estimated average of 115 micrograms per day for women aged 19-40 years based on the regulated level of addition. In practice somewhat higher levels are added to ensure that the product meets the regulated level but at least some of this overage may in turn be lost during storage or cooking. The net result is an intake that is only about one third as high as the recommended supplemental level which nevertheless is highly effective in eliminating folate deficiency in the population and in substantially reducing NTD rates.
These findings led to a reconsideration of a claim linking dietary folate to reduced risk of NTDs.
It is proposed that the Table following B.01.603 be amended to permit the following health claims, the first on any available display surface of the label, and the second divided into two parts because of the complexity of the claim:
Condition for the claim:
It is proposed that the food be required to contain at least 44 μg folate per reference amount and per serving of stated size. The amount of folate present in the food must be stated in the Nutrition Facts table as a percentage of the Daily Value (DV). The DV for folate is 220 micrograms (μg). The current level for an excellent source claim according to the Canadian Food Inspection Agency Guide to Food Labelling and Advertizing is 25% DV or 55 μg. However, under proposed regulatory amendments anticipated regarding the addition of vitamins and minerals to foods, the excellent source claim level is 20% DV. Thus the level of 44 μg would be the new excellent source claim level. This level is close to the 40 μg content that is the condition for the equivalent health claim in the U.S.
Health Canada acknowledges that the current labelling of the folate content of foods does not reflect the latest science related to the bioavailability of the different forms of folate. The Recommended Daily Intake on which the % Daily Value is based is calculated as μg and there is no adjustment for bioavailability. This will continue to be the case until such time as the DVs can be updated to reflect the new Dietary Reference Intakes (DRIs). The minimum folate content for foods which may bear the claim, 44 μg folate, will be the same whether the folate is in the monoglutamate form (folic acid) or the polyglutamate form (naturally occurring folate).
Claims that are referred to as biological role claims are permitted under Part B.01.311 (3) of the Food and Drug RegulationsFootnote 7. In response to an industry request, Health Canada is proposing a biological role claim for folate which recognizes the role of folate as a nutrient in the periconceptional period for the normal development of a healthy brain and spinal cord in the fetus. The proposed biological role claim is as follows:
"Folate is a factor in normal early fetal development."
"Folate is a factor in the normal early development of the fetal brain and spinal cord."
It is proposed that the condition for a food that may bear the biological role claim is that the food contain at least 44 μg folate per reference amount and per serving of stated size. The amount of folate present in the food must be stated in the Nutrition Facts Table as a percentage of the Daily Value (DV). This level is higher than the amount usually accepted for a biological role claim, a level that normally would meet at least the source claim level. The higher level is proposed because the biological basis for the biological role claim is considered to be the same as for the health claim.
Since a claim was already permitted for diets rich in vegetables and fruits and reduced risk of some types of cancer, the Health Canada review of this claim focussed on the relationship between the consumption of dietary fibre and cereal-based foods and cancer. A considerable amount of research has been published since 1993 when the US health claim was accepted. The evidence does not provide consistent support for the relationship between fibre and cancer. Three expert panels have examined the issue and arrived at different conclusions regarding the strength of the association between grain products, dietary fibre and cancer. Published review articles are equally divided on the strength of the association. The Health Canada review concluded that it would be premature at this time to support a health claim that indicates a link between cancer risk and consumption of dietary fibre or cereal products. A copy of the executive summary of the scientific review is attached (Annex 3).
Since the U. S. health claim pertaining to dietary fat and cancer was accepted by the FDA in 1993, there have been numerous studies and reviews published on the subject along with six expert committee reports. The Health Canada review of this evidence concluded that the evidence indicating no relationship between total fat intake and different types of cancers greatly outweighs the evidence for the claim. A copy of the executive summary of the scientific review is attached (Annex 4).
This claim was initially considered by Health Canada to be a "product-specific" claim and was not included in the review of the diet-related health claims in 2000. A product-specific claim applies to a food that has a direct, measurable effect on a body function or structure beyond normal growth and development or maintenance of good health when consumed in a reasonable quantity as part of a diet. Since the cholesterol-lowering action of foods containing oat bran or psyllium depends on the amounts of these ingredients present in the food and on the food matrix and may be affected by processing it was decided at the time of the promulgation of the Nutrition Labelling Regulations that claims for these foods should be assessed on a case-by-case basis. In particular, it was concluded that the notion of solubility of fibre is insufficient to classify fibres in relation to the claimed effect.
This decision has recently been reviewed and Health Canada is reconsidering the conclusion that this is a "product-specific" claim and considering how to handle claims for specific fibre types. Health Canada is therefore prepared to accept submissions for diet-related health claims related to the effect of well-characterized dietary fibre-containing foods on blood lipid levels and heart disease risk where it is possible to identify the characteristics of eligible foods in terms of generic criteria.
Individuals and organizations wishing to comment on this document are asked to respond by February 12, 2007 to:Section Head: Nutrition Labelling and Claims
The full technical reviews including bibliography can be obtained upon request.
1. Notice of a separate consultation on a regulatory framework for expanded authorization of health claims in Canada will be coming in spring 2007.
2. Health Canada will be examining the whole wheat flour standard and seeking to address the fact that it is not consistent with the definition of whole grain.
3. The government of Canada will be publishing proposed regulatory amendments in Canada Gazette Part I as the next step in implementing the revised policy on the addition of vitamins and minerals to foods, later this year.
4. Health Canada is planning to make provision for the addition of folic acid to whole wheat flour.
Health Canada's Scientific Summary on the U. S. Health Claim for Fruit, Vegetables, and Grain Products Containing Fibre, Particularly Soluble Fibre, and Heart Disease
Since the U. S. health claim pertaining to fruit, vegetables, and grain products containing fibre, particularly soluble fibre, and heart disease risk was accepted in 1993, a large amount of new evidence continues to support a claim linking fruit, vegetable, whole grain, and bran intakes to coronary heart disease (CHD) risk reduction. However, the link to soluble fibre specifically has been muddied by a lack of a consistent definition for soluble fibre among researchers and an inability to separate effects attributable to soluble fibre from other components of the food matrix, whether fruit, vegetable, or grain.
A search was conducted for papers published between 1991 and 2000 using Medline, EMBase and Food Science and Technology Abstracts. For Medline the following key words were used: dietary fibre, dietary fiber, cereals, fruit, vegetables, nuts and intersected with the terms cardiovascular disease and hyperlipidemia. For EMBase and Food Science and Technology Abstracts, key words used included cardiovascular diseases, hyperlipidemia, hyperlipaemia, hypertension, hypercholesterol, hyperlipid, cardio, arteri, athero, heart, vascular, vein, venous, artery, cerebrovascular, stroke, cardiac, coronary, and were intersected with fruit, fruits, vegetable, vegetables, nuts, seed, seeds, cereal, cereals, legume, dietary fiber and dietary fibre. The search was limited to papers involving human subjects and those abstracts written in English or French. In addition, a manual scan of the resulting articles was conducted, and papers were excluded if the topic was not relevant to the present claim. Studies were excluded if the dietary intervention was conducted in subjects with diagnosed CHD or with a history of myocardial infarction or coronary bypass surgery. Studies with prudent (i.e. fat restricted) or vegetarian diet interventions were excluded as confounded by major changes in other dietary risk factors such as fat intake. Studies focusing on oats per se were evaluated as a group. Each study was classified by design and evaluated with reference to the Standards of Evidence for Evaluating Foods with Health Claims. Eighty-nine relevant studies were identified, evaluated and summarized but only the 69 studies of acceptable quality were referred to in detail in the report.
Limited support for a relationship between intake of fruits and vegetables and heart disease comes from a few controlled trials with very large changes in either a single fruit or juice (750 ml/d), or total fruit and vegetable intakes (at least 4 servings/d in addition to usual intake) using LDL-cholesterol as a biomarker for CHD risk. A large amount of consistent evidence supporting a risk-reducing effect of fruits and vegetables comes largely from 10 (out of 14 identified) large prospective cohort studies plus 1 case control study.
In the controlled trials with statistically significant results, the single fruits tested were orange juice and guava. Diets incorporating multiple fruits and vegetables included raspberries, honey dew melons, bananas, brussels sprouts, okra, green peas, mushrooms, plums, broccoli, eggplant, carrots, strawberries, tangerines, avocado, fresh figs, cabbage, onions, apples, asparagus, blueberries, mangoes, red peppers, grapes, tomatoes, pears, and kiwi. Other combinations of fruits and vegetables included green leafy vegetables plus peas, (corn- a grain), eggplant, and avocado. In the observational studies, fruits and vegetables included onions and apples, berries, those high in carotenoids, carrots and squash, tomatoes, green leafy vegetables, dried fruit, fresh strawberries and melons, broccoli and brussels sprouts, fresh and dried fruit, raw salad, and fresh fruit and raw vegetables and excluded potatoes, tofu, soybeans, and lentils as vegetables. In some food frequency questionnaires, the fruits and vegetables were not defined. As noted, potatoes were generally excluded; when included, they were not significantly associated with risk reduction. Since potatoes are consumed in large quantities in most North American diets, the inclusion of potatoes as a vegetable in this recommendation could potentially confound the effect of vegetable intake.
The CHD mortality reductions associated with fruit and vegetable intakes ranged from 15 to 37%, with a 20% risk reduction being reported for individuals in the highest quintile of intake (>8 servings/d) compared with those in the lowest (<3 servings/d) in the largest and best- controlled cohort study (Joshipura et al., 2001). Joshipura et al. (2001) estimated that for each 1-serving/d increase in fruit or vegetable consumption, CHD mortality risk was lowered by 4% (RR of 0.96, CI: 0.94-0.99, p = 0.01 for trend). With average daily Canadian intakes estimated at 2 servings/d each of fruit and vegetables, including their juices (or an intake below the 5 to 10 servings/d in Canada's Food Guide to Healthy Eating), based on Nova Scotia and Québec provincial surveys, an increase in intake is feasible.
The recent evidence linking whole grains and brans with CHD risk comes from 22 controlled trials testing the effects of a range of whole grain products or brans on blood lipids. In addition, a few large prospective cohort studies also consistently show a reduction in CHD mortality or in blood lipids, or both, with higher levels of intake of whole grains or of dietary fibre from grains. In the controlled trials, whole grains or brans of rice, barley, wheat, oats, rye, flax, or lime-treated maize husks reduced blood lipids, usually LDL-cholesterol, independent of fat intakes. This lipid-lowering effect was seen in both normo- and hyperlipidemic subjects.
In the cohort studies, "whole grains" have included intakes of dark bread, popcorn, oatmeal, wheat germ, brown rice, bran, bulghur wheat, kasha (buckwheat), couscous (semolina), and those breakfast cereals with >25% whole grain or bran content. The CHD risk reductions across all cohort studies ranged from 21 to 32% after adjustment for other major risk factors. For the best conducted cohort study (Liu et al., 1999), the CHD event risk reduction was 25% comparing the median of the highest versus lowest quintile of whole grain intakes (2.7 vs 0.13 servings/d). Similarly, the adjusted CHD mortality hazard risk ratio in women was 0.82 (p = 0.02 for trend) comparing highest versus lowest quintile of whole grain intakes (3.2 vs 0.2 servings/d) (Jacobs et al., 1999). Thus, an intake of about 3 servings/d of whole grain products was associated with greatest CHD morbidity and mortality reduction in those well conducted studies in which servings of whole grains were assessed. When fibre from cereals was examined in Kushi's 1999 systematic review, significant relative risks ranged from 0.64 to 0.77, similar to those above for whole grain intakes.
A limited number of experimental and observational studies have focused on total dietary fibre per se. The increased fibre intake was achieved from consumption of foods rich in fibre-cereal grains or grains plus fruit and vegetables. However, the 3 experimental studies examining effects of increased dietary fibre intake demonstrated lipid-lowering effects in hypercholesterolemic or hyperlipidemic men and women, limiting the generalizability of these results beyond this at-risk population. The magnitude of effect ranged from 3.3 to 4.9% reductions in blood lipids in addition to independent and significant decreases in cholesterol levels induced by low-fat diets. The observational studies provide additional support for an association between increased fibre intakes and reduced CHD risk. Three out of 4 large prospective cohort studies reported between 25 and 50% reductions in CHD risk comparing higher and lower levels of fibre intake (>20 g /d and <15 g /d, respectively). However, when only fruit- and vegetable-derived fibre intake was examined in three prospective cohort studies, it was not significantly associated with CHD in any study.
Based on the Nova Scotia and Québec provincial surveys, the whole grain and dietary fibre intakes of these Canadian adults are estimated at 2 servings/d and 13 to 15 g /d, respectively. As with fruit and vegetable intakes, an increase in the intake of whole grain products to reduce CHD risk is feasible.
The proposed claim wording is:
"A healthy diet rich in a variety of vegetables, fruits and whole grain products may reduce the risk of heart disease."
Based on the evidence, it is proposed that foods bearing the claim include fresh, frozen, canned, or dried fruit or vegetables, and their juices, as well as products containing at least 51% by weight of the following whole cereal grains: wheat, barley, oats, rye, corn, rice, wild rice, millet, sorghum, teff, triticale, and the pseudo-cereals, i.e. the seeds of specified dicotyledonous plants such as buckwheat, amaranth, and quinoa.
Brans are not included in the health claim because the health benefits of brans may be affected by food processing, e. g ., depending on the type of bran, milling, grinding, extruding or cooking may change its nature and its effects on health.
A fibre criterion is not included because the majority of the evidence is linked to consumption of whole fruits, vegetables, their juices, and to whole grain foods and defined brans. Since it is not possible to distinguish between the fibre from whole grains versus the fibre from other sources it is not appropriate to use fibre as a food compositional criterion for the claim.
The effects of fruits, vegetables, whole grain products are independent of dietary fat content and do not require a low fat diet for the claimed benefit. However, the claim should only be permitted for foods that meet the "low in saturated fatty acids" content claim (containing equal to or less than 2 g saturated and trans fatty acids combined) and contain less than 480 mg sodium per reference amount to avoid a health claim for foods that may contribute to diets associated with potentially adverse health effects due to fat composition or sodium content. This is consistent with the approved claim related to saturated and trans fat and reduced risk of heart disease.
Health Canada's Scientific Summary on Health Claim for Folate and Neural Tube Defects
Since the U. S. Health Claim on folate and neural tube defects (NTDs) was accepted in 1996, evidence continues to support the relationship between folate and NTDs. In addition, an inverse dose-response relationship between folate intake and NTD risk is indicated, at least for dietary folate over a range of intakes from about 100 to about 400 μg dietary folate equivalents (DFE). One study reported the red cell folate associated with lowest risk of NTDs, and a second studied the folic acid intake needed to achieve that level of red cell folate in the general population of women. Recent work has explored the risk associated with common genetic polymorphisms and their relationships with both folate and vitamin B12 status and NTD risk. National trends in several countries in total NTDs have also been reported.
A Medline search was conducted for the period 1995 to December 1999 using the terms folate or folic acid and neural tube defects and human and review which formed the basis of one external reviewer's report. A second Medline search was conducted for the period 1987 to April 2000 using the same terms plus randomized controlled trial, and these references together with the Institute of Medicine (IOM), 1998 Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline provided the basis for the scientific summary. Four randomized controlled trials, two non-randomized interventions, two recent observational studies plus those cited in the IOM report, four reports of NTD prevalence before and after mandatory folic acid fortification of flour in four Canadian provinces, as well as dose response studies relating folate intakes to red blood cell folate and NTD risk formed the evidence of the relationship. Other relevant research regarding genetic polymorphisms related to folate and vitamin B12 metabolism was included in the review.
NTDs are serious and largely preventable birth defects which are associated with genetic predisposition, reproductive history of giving birth to an infant with NTD, folate and vitamin B12 status, maternal diabetes mellitus, maternal obesity, use of anti-convulsant drugs such as valproic acid or carbamazepine, exposure of the mother to hyperthermia during first trimester of pregnancy, and possible environmental factors.
The importance of considering a health claim on folate and NTD risk in the Canadian context is based on two main factors. First, in Canada, until recently, dietary folate intakes have been low, with about half of adult women having reported intakes below the Estimated Average Requirement. In most NTD-affected pregnancies, folate status (red cell folate) tends to be lower than that seen in women with non-affected pregnancies, although still in the normal range for red cell folate in both groups. Since folic acid fortification of flour was mandated in November 1998, folic acid intakes were predicted to improve to a median intake level which would meet the recommended dietary allowances (RDA) for folate for adult women who are not considering pregnancy. A legitimate question arising from this is whether enough dietary folate and folic acid can be reasonably consumed to reduce NTD risk. Secondly, genetic predisposition appears to be relatively common in the population. Common genetic polymorphisms, especially of methylene tetrahydrofolate reductase (MTHFR), a folate- dependent enzyme in the metabolic pathways for DNA precursors and methionine synthesis from homocysteine have been identified. About 12% of the population is homozygous for a polymorphism of MTHFR; in such cases the activity of the enzyme is reduced by about 50 % leading to the suggestion of increased folate requirement for this segment of the population. Those with the polymorphism also have an approximately two-fold increased risk of NTDs, and may account for about 15% of NTD cases. A second common polymorphism, that for methionine synthase reductase (MTRR), an enzyme required for activation of methionine synthase, in conjunction with low B12 status is associated with a five-fold higher risk of NTDs. In one study in Montreal, homozygosity for this polymorphism occurred in 25% of the sample from the general population of women of reproductive age.
While there is consistent evidence that a folic acid supplement of 360 to 800 μg in the periconceptional period reduces the risk of NTDs, only one trial included vitamin B12 as part of the micronutrient supplement, the only trial with 100% reduction in risk of NTDs which was statistically significant. Considerable evidence indicates that B12 status as well as folate status is lower in NTD-affected pregnancies, and one study in Newfoundland indicates a rather high prevalence of low serum B12 in women of reproductive age.
A basic question that must be addressed in a health claim for dietary folate and folic acid is the relative efficacy of each in NTD risk reduction. Three of the four randomized controlled trials (RCT) included groups using folic acid supplements with other micronutrients; one RCT, two non-randomized trials and one community intervention trial used folic acid only. However increasing dietary folate (from naturally occurring food folate sources) was also associated with NTD risk reduction up to a dietary intake of 400 μg folate as DFE, in two case/control studies. In addition, dietary folate and folic acid when consumed in similar amounts based on bioavailability have similar effects on folate status in healthy men and women. Preliminary evidence suggests that the absorption of monoglutamate and polyglutamate forms are similarly absorbed in women with a history of NTD-affected pregnancy, although this should be confirmed in a larger study. However, recently the Institute of Medicine has reported that the absorption of the two forms differ significantly. Taken together, this evidence suggests that both dietary folate and folic acid contribute to folate status and to NTD risk reduction.
A continuous inverse relationship between folate status (red cell folate) and NTD risk has been demonstrated, in one study, such that as red cell folate increases over the range from 0 to 399 μg/L, NTD risk falls. A red cell folate level of 176 μg/L, a level associated with modest reduction in NTD risk, has been associated with a short term intake of food folate of approximately 400 μg/d DFE, and of folic acid of 200 μg. In a second study, an addition of 100 μg or 200 μg folic acid over six months resulted in red cell folate concentrations of 375 and 475 μg/L, levels associated with lowest NTD risk. Thus levels of folic acid intake of about 200 μg per day may be sufficient to achieve increases in red cell folate to levels associated with lowest risk.
Trends in true incidence of NTDs as well as birth prevalence have been declining over the past decades in many countries, including Canada, but the rate of decline has slowed down since 1992, until 1998. After adjusting for secular trends, no significant trend was attributable to preventive strategies. In the reporting countries, the incidence may have reached such a low level that it may not be possible to achieve further reduction. However in Canada, with the introduction of mandatory folic acid fortification of flour in 1998, the impact on the reduction of NTDs has been monitored and results from four provinces show an approximately 50% reduction in NTD prevalence taking into account all births including early terminations of pregnancy. The results of a Canadian research project to conduct a detailed analysis of annual NTD prevalence based on live births, stillbirths, and terminations of pregnancies because of fetal anomalies, prior to any fortification, through the voluntary fortification period and since mandatory folic acid fortification of white flour is expected to be reported soon. The lowest reported true rates are in Hungary at about 0.2 per 1000 where fortification of the staple food, bread, with folic acid, vitamin B12 and B6 has been instituted.
Based on the consistent evidence of a causal relationship between folic acid and NTD, and the supporting evidence of the dose-response relationships for both folate and folic acid on folate status, the association of NTDs with vitamin B12 status, relatively high prevalence of genetic predisposition to NTDs, and taking into account current Canadian recommendations for the preventions of NTDs, the following claim was originally proposed:
"Women who could become pregnant may reduce the risk of having an baby with a brain or spinal cord defect like spina bifida by taking a daily supplement containing 0.4 mg of folic acid, a B vitamin, and consuming a healthy diet rich in folate-containing foods. (Naming the food) is an excellent source of folate."
Following subsequent consumer focus testing of the above statement, the claim was changed as follows:
"Women consuming healthy diets with adequate folate and taking a daily multivitamin supplement containing 0.4 mg folic acid starting at least three months before becoming pregnant may reduce their risk of having a baby with a birth defect of the brain or spinal cord. (Naming the food) is an excellent source of folate."
It is recommended that the claim be permitted for foods containing at least 44 μg folate per reference amount. This represents 20% of the Daily Value for folate, based on the 1990 Recommended Nutrient Intake for folate for women not intending pregnancy.
Health Canada Scientific Summary on the U. S. Health Claim on Fibre-Containing Grain Products, Fruits and Vegetables and Cancer
Since the U. S. health claim pertaining to a diet rich in fibre-containing grain products, fruits, and vegetables was accepted in 1993, a considerable amount of research has been published examining the relationship between cancer and consumption of dietary fibre and cereal foods. Four randomized dietary intervention trials have been conducted in the past few years with patients diagnosed with adenomatous polyps, presumed precursors of colorectal cancer, and several cohort studies have been completed. These studies extended the extensive animal literature that examined the potential link between consumption of dietary fibre and a reduced risk of cancer.
A Medline search was conducted for the period 1993-2000 that included the terms "dietary fiber AND (grains OR cereals OR legumes) AND neoplasms NOT (fruit OR citrus OR vegetables)". A further Medline search was conducted for the period January 1996 to April 2000 using the following key words: cereals, whole grains, neoplasms, and human. The search was expanded to Medline, CAB, Food Science and Technology Abstracts and EMBase for the terms "whole grain OR wheat OR oat OR rye OR barley OR rice OR corn OR cereals" and "cancer OR tumour OR neoplasm OR neoplasms". These articles were screened by title/key words/abstracts for relevance to the subject. All articles were in English or French. Several expert consensus reports were identified including the World Cancer Research Fund/American Institute for Cancer Research 1997 report. The review focussed on this and research conducted since 1996, including 4 controlled trials, 9 cohort studies, 16 case-control studies and 5 ecological studies.
Cancer is a major public health problem affecting approximately 40% of males and 36% of females over their lifetimes. Cancer incidence increases dramatically with age: between the ages of 40-69, the risk of cancer more than doubles for every 10 additional years of age. Risk factors for cancer include non-dietary environmental factors, lifestyle factors, and genetic pre-disposition. However, dietary factors also play a major role.
The fundamental question addressed by this report is whether increasing consumption of diets high in fibre and of cereal foods can have a significant effect on lowering the risk of cancer. The relationship between fruit and vegetable consumption and risk of cancer has been addressed in a previous report (Health Canada, 2000) where it was concluded that sufficient scientific evidence existed to support a Health Claim stating that diets high in fruit and vegetable may lower the risk of some cancers. Thus, the present report focuses on dietary fibre and, specifically, cereal foods.
The evidence presented in the current report does not consistently support a health claim linking dietary fibre, grain products and a lower risk of cancer. Three different expert panels have examined this question and have arrived at different conclusions regarding the strength of the association between grain foods, dietary fibre and cancer. Literature review articles are equally divided about the strength of the association. For colorectal cancer, four randomized intervention trials have failed to demonstrate an effect of diets high in fibre and/or grain supplements on the recurrence of adenomatous polyps in patients with a history of such polyps. In addition, most prospective cohort studies found no effect of grain consumption on cancer risk. The data also fail to support a convincing effect of dietary fibre on cancer.
Part of the problem in determining whether a relationship exists between dietary fibre or grain products and cancer has been methodological. Several different methods have been used to measure the dietary fibre content of foods in nutritional databases. In addition, it is possible that associations between cereal intake and cancer are influenced by methods of processing of the cereals, a factor which has not been assessed consistently or extensively in the literature. An effect of processing is suggested both by plausible biologic mechanisms and by four case-control studies that examined the link between refined grain intake and risk of colon cancer, all of which found a statistically significant higher risk of colon cancer with increasing refined grain intake. These considerations, together with the lack of consensus from expert panels and the literature, indicate that it would be premature at this time, to support a Health Claim that indicates a link exists between cancer risk and consumption of dietary fibre or cereal foods.
Health Canada Scientific Summary on the U. S. Health Claim Regarding Dietary Fat and Cancer
Since the U. S. health claim pertaining to dietary fat and cancer was accepted in the U. S. in 1993, new evidence has weakened the support for this claim.
The searches to update the evidence included Medline from 1993 to December 2003 inclusive, Food Science and Technology Abstracts for the period 1997 to 2002 and Current Contents from 1998 to 2002. Key words fat, dietary fat, fat intake, saturated fat, saturated fatty acids and meta analysis were intersected with the words cancer, breast cancer, prostate cancer, gastric cancer, colon cancer, colorectal cancer, rectal cancer, lung cancer, oesophagus cancer, endometrial cancer, testicular cancer and carcinogenesis. The search was limited to papers involving human subjects and published in English. Manual searches were also made of primary studies and reviews for additional papers not identified in the electronic search. Experimental studies were excluded if the dietary intervention was conducted in subjects with diagnosed cancer. Each study was classified by design type and evaluated for quality with reference to the Standards of Evidence for Evaluating Foods with Health Claims. Four controlled trials, 18 cohort studies and 60 case-control studies of acceptable quality of 63 identified were included in the evaluation.
Several large prospective cohort studies have examined the relationship between dietary fat and risk of breast, prostate and colon cancer in particular. For the nine cohort studies focussing on breast cancer risk, only one found a relationship with both total fat and saturated fat intake, one identified an association with saturated fat only, two identified an inverse association with monounsaturated fatty acids (MUFA) while one found a positive association with MUFA. Of the three studies that assessed trans fatty acid intake, one identified an increased risk of breast cancer with trans fatty acid intake, one found an decreased risk with trans fatty acid intake, and one found no effect. For the three prospective cohort studies focussing on prostate cancer, energy-adjusted total fat intake was not associated with total prostate cancer risk in any of these studies. Eight of nine cohort studies focussing on colon cancer found no relationship with total fat intake.
In addition six expert committee reports (Food and Agriculture Organisation of the United Nations / the World Health Organisation (FAO/WHO), 1994; The World Cancer Research Fund / the American Institute for Cancer Research (WCR/AICR), 1997; The Committee on Medical Aspects of Food and Nutrition Policy (COMA), UK, 1998 (Gurr, 1998); WHO, 1999 (Scheppach et al.,1999); the Institute of Medicine(IOM), 2002 and FAO/WHO, 2003) have been published during this period as well as several systematic reviews. Among the expert reports, the first, that of the FAO/WHO on Fats and Oils in Human Nutrition (1994), concluded that cohort and case-control studies cast some doubt on animal studies and inter-country correlations linking dietary fat with cancer of the breast, colon, pancreas and prostate, but commented that there were serious limitations in case-control and cohort studies.
The WCR/AICR (1997) concluded that "there is a consistent pattern suggesting that diets high in total fat possibly increase the risk of lung, colorectal, breast and prostate cancers. Diets high in fat increase the risk of obesity; therefore high-fat diets are an indirect risk factor for cancers, the risk of which is increased by obesity." This tentative conclusion was based on early case-control studies which showed a relationship between total fat intake and these cancers.
The COMA, UK stated that "in a rigorous review of the literature, the authors found little evidence for a strong association between the intake of total fat or of individual fatty acids and any type of cancer" (Gurr, 1998).
A WHO concensus statement, 1999, on fat intake and promotion of cancer was that "fat intake is probably associated with colorectal cancer risk. The data available are not sufficient to identify clearly the role of total fat, compared with specific types of fat" (Scheppach et al.,1999).
The IOM (2002) recommended an acceptable macronutrient distribution range (AMDR) for fat to be 20 to 35 percent of energy for adults. Reduction in risk of cancer was not a factor in setting the AMDR for fat due to insufficiency of the data to determine a defined level of fat intake for prevention of chronic disease.
The most recent joint FAO/WHO report Diet, Nutrition and the Prevention of Chronic Diseases (2003) concluded that the evidence does not support a relationship between dietary fat intake and the increased risk of breast, prostate, colorectal and other cancers.
Overall the scientific evidence of an association between dietary fat intake and incidence of breast, prostate and colon cancer has weakened over the past ten years. Although cross sectional population studies continue to provide some support for the relationships between breast cancer and fat components and between colorectal cancer and animal fat intake, prospective cohort and case-control studies generally do not. The primary change in the literature has been the softening of support for the relationship on the basis of case-control studies especially where relative risks and odd ratios have been adjusted for energy intake. Further, several recent large cohort studies did not support a relationship between dietary fat intake and breast, prostate or colon cancers. There is also increased inconsistency in the relationship between specific foods and cancer. Evidence for an effect of meat, in particular red meats, on cancer risk has not been
consistently supported by case control and cohort studies reported during the past 10 years.
The evidence indicating no relationship between total fat intake and different types of cancers greatly outweighs the evidence for the claim and thus it is recommended that Canada does not accept a health claim for an association between dietary fat and cancer.
"drug" includes any substance or mixture of substances manufactured, sold or represented for use in the (a) diagnosis, treatment, mitigation or prevention of a disease, (bold added) disorder or abnormal physical state, or its symptoms, in human beings or animals, (b) restoring, correcting or modifying organic functions in human beings or animals, (c) disinfection in premises in which food is manufactured, prepared or kept;
s3(1) No person shall advertise any food, drug or cosmetic device to the general public as a preventative, treatment or cure for any of the diseases, disorders or abnormal physical states referred to in Schedule A.
B.01.601 (1) A food with a label or advertisement that carries a statement or claim set out in column 1 of the table following section B.01.603 is exempt from the provisions of the Act and its Regulations with respect to drugs and from subsections 3(1) and (2) of the Act, if (a) the food meets the applicable conditions set out in column 2.
A health claim related to vegetables and fruit and reduced risk of some types of cancer has already been approved in the Food and Drug Regulations (Table following B.01.603). This proposed wording would permit a combined claim for the two relationships.
B.13.005 (b) shall contain the natural constituents of the wheat berry to the extent of not less than 95 per cent of the total weight of the wheat from which it is milled;
Section B.01.001 "available display surface", in respect of a prepackaged product, means
(a) the bottom of an ornamental container or the total surface area of both sides of a tag attached to the ornamental container, whichever is greater,
(b) the total surface area of both sides of a tag attached to a package to which a label cannot be physically applied or on which information cannot be legibly set out and easily viewed by the purchaser or consumer under the customary conditions of purchase, and
(c) the total surface area of any other package, excluding the bottom if the contents of the package leak out or are damaged when the package is turned over, but does not include
(d) any area of a package on which a label cannot be physically applied or on which information cannot be legibly set out and easily viewed by the purchaser or consumer under the customary conditions of purchase,
(e) any part of a package that is intended to be destroyed when it is opened, other than a package of a food that is intended to be consumed by one person at a single eating occasion, or
(f) the area occupied by the universal product code; (surface exposée disponible)
"Subject to section B.01.311, the label of or advertisement for a food may carry a statement or claim to the effect that the food's energy value or a nutrient contained in the food is generally recognized as an aid in maintaining the functions of the body necessary to the maintenance of good health and normal growth and development."