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New dietary guidelines officially endorsed by the U.S. government were and were immediately greeted with criticism.
The guidelines are roughly similar to the previous version, issued in 2010, but with an added focus on dietary patterns rather than on individual foods, and a new recommendation that fewer than 10% of calories per day should be from added sugars.
They also depart in several respects from recommendations given last year by the U.S. Dietary Guidelines Advisory Committee (DGAC).
As a result, the final guidelines were criticized sharply by both sides: those who stood by the DGAC recommendations and those who found those to be lacking.
"These guidelines are effectively useless," said , at Yale University, in an email to 木瓜直播, adding that Americans should rather follow the advisory committee's report, which is still online.
"Very disappointing," said , at the T.H. Chan School of Public Health at Harvard.
Influential food researcher and blogger , at New York University, applauded the focus on dietary patterns but pointed out that the report relies on euphemisms, urging Americans to cap sugar intake as a proportion of total caloric intake. , she said she would have preferred an explicit call to limit sugar-sweetened beverages.
But other researchers applauded the guidelines for keeping them consistent with years past.
"I think they did a really good job, and I applaud them for that," said , founder and president of the Preventive Medicine Research Institute, in an interview with 木瓜直播.
And, in a statement, the American Medical Association (AMA) expressed solid support for the new dietary guidelines without hint of criticism.
"The AMA applauds the Committee for recommending that our nation's children and adults should focus on achieving a healthy overall diet rather than focus on consuming only specific nutrients," wrote , AMA president. "With obesity and its associated health consequences -- namely type 2 diabetes and cardiovascular disease -- on the rise throughout our country, the AMA also is extremely pleased that the new recommendations call for significantly reducing the amount of added sugars and sugar sweetened beverages from the American diet."
The Basics
"Eating pattern may be more predictive of overall health status and disease risk than individual foods or nutrients," according to the published guidelines, issued jointly by the U.S. Department of Agriculture and the Department of Health and Human Services. The guidelines have been updated every 5 years since 1980.
Despite the focus on dietary patterns, the new guidelines do recommend that certain nutrients be capped. In addition to the sugar cap, it's recommended that people consume fewer than 10% of calories per day from saturated fats, and less than 2,300 mg per day of sodium. But, in line with the DGAC recommendation, there is no cap on total fat.
Similar to the previous guidelines, Americans are encouraged to eat a variety of vegetables and fruits, with grains, fat-free or low-fat dairy, and oils. "A healthy eating pattern limits saturated fats and trans fats, added sugars, and sodium," the authors wrote.
Also new: the former cholesterol limit of 300 mg/day has been dropped. But , the president of the American College of Cardiology, pointed out in an email to 木瓜直播 that there's still a focus on cholesterol in the guidelines: "The USDA Food Patterns are limited in saturated fats, and because of the commonality of food sources of saturated fats and dietary cholesterol, the Patterns are also low in dietary cholesterol," the authors of the guideline wrote.
There was also a prompt to eat "a variety of protein foods, including seafood, lean meats and poultry, eggs, legumes (beans and peas), and nuts, seeds, and soy products." The authors of the report added that two further aims of the report are to get people to shift to healthier food and beverage choices and to "Support health eating patterns for all."
Physical activity was mentioned briefly in the report. "They mention all Americans should meet the physical activity guidelines for Americans as well," wrote , at the University of Rochester in New York.
"We talk about health literacy a lot more now in health care and this applies to many areas. It's not just about knowing which medications you take, how much and when. Nutrition is right at the top of that health literacy pillar," Cook added.
Nutritionists Disappointed
Several scientists expressed frustration in what they saw as clouded and euphemistic language.
Katz said that the guidelines are "a virtuoso display of linguistic contortionism" that remove the clarity of the advisory committee's report.
Nestle, who was a peer reviewer of an earlier version of the guidelines, wrote, "These Dietary Guidelines, like all previous versions, recommend foods when they suggest 'eat more.' But they switch to nutrients whenever they suggest 'eat less'," on .
Nestle added that "sodium" is a euphemism for processed foods and junk foods, and "saturated fat" is a surrogate for meat. She wrote that she wished the guidelines would come out with more clarity.
Katz agreed, noting that "any guidance to limit any particular foods is buried deep within passages in the chapter on 'shifts,' and even them, foods to limit are very effectively de-emphasized."
, at the University of North Carolina, also wished the guidelines had come out stronger against soda. They do mention sugar-sweetened beverages, but indirectly and in the middle of the long report, stating simply that "[t]he two main sources of added sugars in U.S. diets are sugar-sweetened beverages and snacks and sweets."
The report also mentioned processed meats, but in the context of endorsing their limited consumption. "Processed meats and processed poultry are sources of sodium and saturated fats, and intake of these products can be accommodated as long as sodium, saturated fats, added sugars, and total calories are within limits in the resulting eating pattern," it said.
Politics Intrude?
The guidelines indicate that a can be very healthy, but don't specifically discuss red meat, which the DGAC had singled out as unhealthy. Nor do they address environmental sustainability, another issue emphasized by the DGAC.
Several of the nutritionists told 木瓜直播 that political pressure from Congress had led to these omissions from the final guidance.
"The USDA censored the scientific advisory committee report by saying nothing about reducing consumption of red and processed meat; they only talk about eating lean meat," wrote Willett in an email to 木瓜直播. He added that the scientific advisory committee was "very clear about adverse health effects of red and processed meat."
, also at Harvard, wrote, "The censoring of the environmental effects was very unfortunate but expected, due to congressional action, but taking out advice to eat less red meat is flat out in opposition to what the committee recommended for straightforward dietary advice, based on strong science.
"This is apparently due to lobbying by the beef industry and a clear case of politics overriding science," he added.
Ornish said he understood why the guideline authors removed the sustainability portion, but said it was unfortunate that they did. "It was too bad that they had a lot of political power from vested interests."
A summary of the guidelines was also published in the .