Thursday, August 12, 2010

From the Los Angeles Times

The U.S. Dietary guidelines -- the advice that Americans are issued to help us eat healthier -- aren't working very well judging by the number of people who are overweight, obese or have nutrition-related illnesses. That may be because the guidelines aren't paying enough attention to food, according to a commentary released Tuesday.

The dietary guidelines and recommended dietary allowances, or RDAs, were formulated about 70 years ago to target illnesses related to nutritional deficiencies, such as vitamin D and rickets. But nutritional deficiencies that cause rickets and scurvey and beriberi aren't as common today. And, the authors noted: "the greater the focus on nutrients, the less healthful foods have become."

The commentary, written by two nationally recognized experts in nutrition and nutrition-related illness, states that the nation has gone astray by focusing on the nutritional components of food, such as various types of fat, sugars and vitamins. Instead, people should be advised to focus on foods, such as emphasizing the consumption of whole foods over processed foods, which would reduce salt intake among other benefits; and fruits and vegetables, which would increase vitamin and fiber intake.

The argument is convincing. For example, the authors said, the dietary guidelines focus on advice such as "avoid too much fat, saturated fat, cholesterol." But, despite attempts to simplify food labels, "few individuals can accurately gauge daily consumption of calories, fats, cholesterol, fiber, or salt."

The RDAs are based on carbohydrates, proteins and fats despite the fact that various foods within each of these groups can have much different health effects. For example, chicken, fish, beans and nuts are all proteins.

It's probably the combination of nutrients in foods and the makeup of the diet over the long-term that influences nutrition-related illnesses, such as heart disease and some types of cancer. . . .individual compounds in isolation have small effects on chronic disease," the authors wrote.

Moreover, the dietary guidelines are often misused by food manufacturers. Based on the addition of a few ingredients, foods can be advertised as healthy.

"Taking the nutrient approach to self-serving extremes, the food industry 'fortifies' highly processed foods, like refined cereals and sugar-sweetened beverages, with selected micronutrients and recharacterizes them as nutritious," wrote the authors, Dr. Dariush Mozaffarian and Dr. David S. Ludwig, both of Harvard Medical School." The commentary was released Tuesday in the Journal of the American Medical Assn.

Nutritional science should not be abandoned, they said. But the focusing on nutrients over foods "contributes to confusion, distracts from more effective strategies, and promotes marketing and consumption of processed products that normally meet selected nutrient cut points but undermine overall dietary quality." 

Anyone for peaches, rice and fish instead of vitamin C, starch and omega-3 fatty acids? 

-- Shari Roan / Los Angeles Times

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