Proposed Canada Food Guide called "obesogenic"
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《加拿大医疗协会学报》
The proposed revised Canada Food Guide is a recipe for dramatic increases in premature death resulting from chronic diet-related disease, some critics say.
Figure. Health Canada's proposed food guide could prove less than fruitful, say critics. Photo by: Canapress
Bill Jeffery, the Canadian coordinator for the US-based Centre for Science in the Public Interest, says he can't fathom the rationale behind recommending lower consumption of fruits and vegetables (for most categories, a daily intake of 5–8 servings, as opposed to the 5–10 recommended in the 1992 edition) and more consumption of meat (an intake of 4 servings for men, instead of the 2–3 urged in 1992).
"It will be disastrous for the health of Canadians," Jeffery says, noting that over 25 000 Canadians die prematurely each year because of diet-related diseases and that the WHO estimates nearly 5 years is shaved off life expectancy because of diet-related risk factors such as low fruit and vegetable intake.
But Health Canada says the revised guide has undergone "comprehensive" scientific review and will promote weight loss while preventing the onset of chronic disease, contends Mary Bush, director-general of the office of nutrition policy and promotion. (The revised guide was taken off the Health Canada Web site during the federal election. "We're awaiting direction before resuming consultations," spokes-person Renee Bergeron says.)
The 1992 version of the guide was considered the Canadian "bible" of nutrition, with some 24 million copies distributed nationwide.
Health Canada's review of the Guide began in 2003 and included stakeholder meetings and surveys of professionals and consumers. In the fall of 2005, Health Canada proposed a fold-out, 8-page guide to replace the current 2-sided single sheet. It retains the concept of 4 core food groups — fruits and vegetables, grain products, milk products, and meats and alternatives — while adding 6 pages of advice on issues ranging from healthy eating and shopping tips to reading labels.
More substantively, the proposed guide tailors nutritional advice to age and gender, while providing more specificity on suitable serving sizes. Instead of advising everyone to, for example, eat 5–10 servings of fruits and vegetables daily, the new guide recommends different daily intakes for 9 demographic categories: preschoolers, and 4 age groups (4–13, 14–18, 19–50 and over 50), divided by gender.
Dr. Yoni Freedhoff, an Ottawa specialist in obesity medicine, identifies a number of deficiencies in the proposed guide: inadequate recognition of the value of consuming more polyunsaturated fatty acids or more whole-grain products; a complicated and confusing array of recommended serving sizes; a total lack of guidance on recommended daily caloric intake; and insufficient warnings about the dire consequences of eating high calorie foods in the so-called "others" category. Canadians now consume about 600–800 calories worth of fried foods and sugary desserts in this category.
"It's obesogenic," says Freedhoff. With help from a dietician, he calculated that the fewest calories anyone scrupulously following the new guide would consume daily is 1700 (females aged 19–50), assuming they only drank water, didn't use salad dressing or have dessert. In other demographic categories, the daily intake topped 3200 calories, again without extras.
"What it means is that should anybody who is of average height and size follow Canada's Food Guide, there is a very, very good chance it will lead to weight gain."
Both Freedhoff and Jeffery also chide Health Canada for failing to furnish the scientific rationale for the changes and allowing industry representatives to sit on its external Food Guide Advisory Committee. The 12-member committee includes representatives from Food and Consumer Product Manufacturers of Canada, the Vegetable Oil Industry Council and the BC Dairy Foundation.
"It's obscene that industry is involved," Freedhoff says. "I would not have Exxon developing Canada's energy policy."
Health Canada's Bush says such criticism is unfounded. Representatives of industry and other stakeholders were involved because "philosophically, we absolutely believe that if we're going to improve the nutritional health of Canadians, it takes all sectors to . . . understand their role."
As for the changes, they're rooted in "comprehensive" internal reviews of nutrient standards recently developed by the US Institute of Medicine, WHO's 2003 report on Diet, Nutrition and Prevention of Chronic Disease and a 2005 US Dietary Guidelines Advisory Committee report.
Bush also dismisses concerns the guide will contribute to obesity or encourage consumption of fewer fruits and vegetables. Rather, it offers a greater degree of specificity and precision by demographic group, she argues.
None of the changes are written in stone, Bush adds, as Health Canada will complete consultations and conduct focus group testing before releasing the finished product — probably later this year. Both exercises were suspended until after the federal election, which may give influential groups such as the Dietitians of Canada time to weigh in — provided its members can reach a consensus, says director of policy Lynda Corby.
Others are convinced Health Canada is on the right track. "Overall, the direction seems appropriate," says Elinor Wilson, CEO of the Canadian Public Health Association.
"Given the obesity epidemic, promoting healthy eating is an important part of public policy," says Dr. Arya Sharma, chair of the Canadian Obesity Network. The guide is not a treatment for obesity, or diabetes or any other medical condition, he adds. "This is for someone who is healthy and wants a healthy diet."
Sharma believes the proposed guide is based on the best available science, but acknowledges that contradictory evidence is common in the nutrition sciences.
But Jeffery is so persuaded the revisions aren't evidence-based that he recommends Canadians look to the "Healthy Eating Pyramid" developed by Dr. Walter Willett at the Harvard School of Public Health as a superior, independent alternative for nutrition advice.(Wayne Kondro)
Figure. Health Canada's proposed food guide could prove less than fruitful, say critics. Photo by: Canapress
Bill Jeffery, the Canadian coordinator for the US-based Centre for Science in the Public Interest, says he can't fathom the rationale behind recommending lower consumption of fruits and vegetables (for most categories, a daily intake of 5–8 servings, as opposed to the 5–10 recommended in the 1992 edition) and more consumption of meat (an intake of 4 servings for men, instead of the 2–3 urged in 1992).
"It will be disastrous for the health of Canadians," Jeffery says, noting that over 25 000 Canadians die prematurely each year because of diet-related diseases and that the WHO estimates nearly 5 years is shaved off life expectancy because of diet-related risk factors such as low fruit and vegetable intake.
But Health Canada says the revised guide has undergone "comprehensive" scientific review and will promote weight loss while preventing the onset of chronic disease, contends Mary Bush, director-general of the office of nutrition policy and promotion. (The revised guide was taken off the Health Canada Web site during the federal election. "We're awaiting direction before resuming consultations," spokes-person Renee Bergeron says.)
The 1992 version of the guide was considered the Canadian "bible" of nutrition, with some 24 million copies distributed nationwide.
Health Canada's review of the Guide began in 2003 and included stakeholder meetings and surveys of professionals and consumers. In the fall of 2005, Health Canada proposed a fold-out, 8-page guide to replace the current 2-sided single sheet. It retains the concept of 4 core food groups — fruits and vegetables, grain products, milk products, and meats and alternatives — while adding 6 pages of advice on issues ranging from healthy eating and shopping tips to reading labels.
More substantively, the proposed guide tailors nutritional advice to age and gender, while providing more specificity on suitable serving sizes. Instead of advising everyone to, for example, eat 5–10 servings of fruits and vegetables daily, the new guide recommends different daily intakes for 9 demographic categories: preschoolers, and 4 age groups (4–13, 14–18, 19–50 and over 50), divided by gender.
Dr. Yoni Freedhoff, an Ottawa specialist in obesity medicine, identifies a number of deficiencies in the proposed guide: inadequate recognition of the value of consuming more polyunsaturated fatty acids or more whole-grain products; a complicated and confusing array of recommended serving sizes; a total lack of guidance on recommended daily caloric intake; and insufficient warnings about the dire consequences of eating high calorie foods in the so-called "others" category. Canadians now consume about 600–800 calories worth of fried foods and sugary desserts in this category.
"It's obesogenic," says Freedhoff. With help from a dietician, he calculated that the fewest calories anyone scrupulously following the new guide would consume daily is 1700 (females aged 19–50), assuming they only drank water, didn't use salad dressing or have dessert. In other demographic categories, the daily intake topped 3200 calories, again without extras.
"What it means is that should anybody who is of average height and size follow Canada's Food Guide, there is a very, very good chance it will lead to weight gain."
Both Freedhoff and Jeffery also chide Health Canada for failing to furnish the scientific rationale for the changes and allowing industry representatives to sit on its external Food Guide Advisory Committee. The 12-member committee includes representatives from Food and Consumer Product Manufacturers of Canada, the Vegetable Oil Industry Council and the BC Dairy Foundation.
"It's obscene that industry is involved," Freedhoff says. "I would not have Exxon developing Canada's energy policy."
Health Canada's Bush says such criticism is unfounded. Representatives of industry and other stakeholders were involved because "philosophically, we absolutely believe that if we're going to improve the nutritional health of Canadians, it takes all sectors to . . . understand their role."
As for the changes, they're rooted in "comprehensive" internal reviews of nutrient standards recently developed by the US Institute of Medicine, WHO's 2003 report on Diet, Nutrition and Prevention of Chronic Disease and a 2005 US Dietary Guidelines Advisory Committee report.
Bush also dismisses concerns the guide will contribute to obesity or encourage consumption of fewer fruits and vegetables. Rather, it offers a greater degree of specificity and precision by demographic group, she argues.
None of the changes are written in stone, Bush adds, as Health Canada will complete consultations and conduct focus group testing before releasing the finished product — probably later this year. Both exercises were suspended until after the federal election, which may give influential groups such as the Dietitians of Canada time to weigh in — provided its members can reach a consensus, says director of policy Lynda Corby.
Others are convinced Health Canada is on the right track. "Overall, the direction seems appropriate," says Elinor Wilson, CEO of the Canadian Public Health Association.
"Given the obesity epidemic, promoting healthy eating is an important part of public policy," says Dr. Arya Sharma, chair of the Canadian Obesity Network. The guide is not a treatment for obesity, or diabetes or any other medical condition, he adds. "This is for someone who is healthy and wants a healthy diet."
Sharma believes the proposed guide is based on the best available science, but acknowledges that contradictory evidence is common in the nutrition sciences.
But Jeffery is so persuaded the revisions aren't evidence-based that he recommends Canadians look to the "Healthy Eating Pyramid" developed by Dr. Walter Willett at the Harvard School of Public Health as a superior, independent alternative for nutrition advice.(Wayne Kondro)