As those of you who read my blog know, I find it disheartening when a syndicated columnist writes about research or nutrition and fails to do so accurately. I've previously pointed to errors in the column, The Lean Plate Club, penned by Sally Squires in the Washington Post. Today, again, she gives me one more reason to write about her misinformation and inaccuracies.
Her column today is titled "The Protein Solution" and opens with surprisingly positive sentences about eating more protein - To reach a healthier weight with fewer hunger pangs, consider eating more lean protein. A new study adds to a growing body of research that points to protein's power to satisfy hunger better than either fat or carbohydrates.
From there it's downhill as she tries to make the data fit her opinion, that low-fat is the only healthy option. And, hey, she is entitled to her opinion - my problem is with her ommissions and dismissal and/or ignoring fact.
The findings could also help explain the recent but short-lived enthusiasm for low-carb diets, which happen to be high in protein.
What is her definition of "high protein" and exactly which low-carb diets is she writing about?
The low-carb diets all include advice to eat more protein foods, and yet, none that I've crunched menus for exceed the 35% of calories from protein the Institute of Medicine [IOM] feels is the upper limit of Adequate Intake. In fact, most fall within 20-30% of calories from protein and are better described as "high fat" since restricting calories from carbohydrate typically requires higher amounts of fat, often exceeding the upper limit of 35% of calories from fat, a level the IOM believes is the upper limit for fat intake.
And this "short-lived enthusiasm" for low-carb diets - is it true?
A just released survey from the Harvard School of Public Health found that in 2004 36% of respondents were keeping track of their carbohydrate intake and in 2005 the same percentage, 36% still kept track of their carbohydrate intake. Where there has been a significant waning in interest is in the use of products touted as "low-carb" - sales for such products has been declining for well over a year now.
However, two noteworthy indicators provide more insight. One - sales of whole foods those following a low-carb diet rely on - eggs, cheese, edible oils, meat, poultry, nuts, seeds, fresh produce, fish, etc. - remain strong or continue to rise for sales. Two - research funding continues to be strong in the area of low-carb nutrition - the data is compelling and scientists continue to investigate the low-carb dietary approach for weight loss, diabetes and other health issues.
Let's not mistake product failure with declining interest in the low-carb dietary approach - whole foods remain strong as does the interest from the scientific community...two indicators that are more important than the sale of processed foods touted as low-carb.
Ms. Squires relies on a quote from a "biased" source, Arne Astrup.
"It's telling us that one of the reasons why the low-carbohydrate diets seemed to work is not because of low carbohydrates, but because of high protein," said Arne Astrup, head of the department of human nutrition at the Royal Veterinary and Agricultural University in Copenhagen. "Look at Atkins, South Beach and the Zone," said Astrup, who wrote an editorial accompanying the protein study, which appears in this month's American Journal of Clinical Nutrition. "They're all characterized as having 30 to 40 percent of calories from protein."
Now you may be wondering why I consider Dr. Astrup to be biased. Well, Ms. Squires fails to disclose that Dr. Astrup is medical advisor to Weight Watchers in Denmark. His department at the university has also received funding from over 50 Danish and international food companies.
I think her readers deserve to know any potential conflict-of-interest from whom she is quoting, don't you?
Thirty percent of daily calories as protein -- about twice what most Americans eat, and the upper limit recommended by the Institute of Medicine -- is the amount that University of Washington researchers gave to 19 participants in the latest study.
Ms. Squires incorrectly states the upper limit for protein as 30% of calories from protein. The Institute of Medicine website provides access to their macronutrient distribution recommendation documents which are found here: Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids
The correct upper limit is 35% of calories from protein as determined by the IOM. It is noteworthy that even at this level, the IOM documentation states that, "no defined intake level at which potential adverse effects of protein was identified." It continues with the explanation that the range of protein advised is to "complement" the percentages from carbohydrate and fat!
So, quite frankly, even that 35% upper limit intake is not an evidence-based recommendation, it was designed to fit the low-fat recommendations.
Ms. Squires continues to put forth the myth that higher protein in the diet is dangerous to those with normal kidney function.
Even so, Weigle and others caution that boosting protein to 30 percent of daily calories may not be safe for everyone, since it could overtax kidneys in those with kidney problems, diabetes or glucose intolerance.
While those who have existing kidney problems should understand the potential risk of high protein diets and work closely with their physician to determine if increasing protein is appropriate, those who have normal kidney function - including diabetics and those with glucose intolerance - are at no increased risk for degradation of their kidney function. This is based on decades of research data which has shown that increased protein does not cause kidney disease.
A broad, sweeping generalization that, in fact, may prove disasterous in terms of health.
For others trying to reach a healthier weight, Astrup said that the latest findings show "that there's no reason to cut down on carbohydrates or that much on fat. Simply increase your protein. That can be done as part of a very healthy diet, including eating all kinds of fruit, vegetables and whole grains."
No reason to cut down on carbohydrate?
While Dr. Astrup includes eating fruits, vegetable and whole grain as part of the diet, he fails to adequately address the carbohydrates one needs to seriously consider limiting - refined sugar, refined grains, high fructose corn syrup, and processed foods that often are not only high in added sugars but also contain trans-fats!
Without stating the types of carbohydrate foods that are potentially nutritionally bankrupt, he and Ms. Squires leave the reader with the impression that anything they want to eat that's carbohydrate is A-Okay. A steady diet of processed, sugar laden foods, high in carbohydrate offer little in the way of nutrient density and are best viewed as "empty calories" that displace calories from better nutrient-dense foods.
This should have been clearly stated for readers to understand that in the study in question, participants ate nutrient-dense carbohydrates - fruits, vegetables, whole grains and legumes - and did not eat just any carbohydrates they wanted to in their diet!
The continued perpetration of fat-phobic recommendations for weight loss.
Ms. Squires wraps up her column with a number of recommendations to keep the level of fat calories low while increasing protein intake. In doing so, she ignores the evidence that finds that increased fat intake while reducing carbohydrate intake works for weight loss while also improving health risk factors.
I personally have no problem with anyone wanting to eat a diet that is lower in fat, but to continue to put forth opinions that imply an increased fat intake is harmful in the context of a low-carb diet, is, in my opinion, irresponsible. The data clearly shows that when carbohydrate is restricted, protein is adequate and fat is inevitably increased, calorie reduction is spontaneous (no calorie counting is required), weight is lost (with a sparing effect on lean body mass) and risk factors such as cholesterol, triglycerides, CRP and glucose tolerance all improve.
Now while this particular study was low in fat and calorie reduction was also spontaneous, the researchers DID NOT analyze the effect such a dietary approach had on cholesterol, triglycerides or CRP in the blood. Without this data we simply do not know if a diet higher in protein, stable with carbohydrate and lower in fat has the same positive effect on these risk factors.