I was pretty excited to see in my inbox a study published in The Annals of Internal Medicine. Funded by the National Institutes of Health, it was a randomized controlled trial (RCT) to show the superiority of low-carb over low-fat dieting for losing weight. The result showed the superiority of low-carb over low-fat in the primary end point of the hypothesis being tested: improving heart disease risk, using all the classical markers for determining that risk.
The study, “Effects of Low-Carbohydrate and Low-Fat Diets: A Randomized Trial,” was performed at the Tulane University School of Public Health in New Orleans. It enlisted a diverse population of 148 men and women without either clinical cardiovascular disease or diabetes. The study DESIGN: “A randomized, parallel group trial. The OBJECTIVE: “To examine the effects of a low-carbohydrate diet compared with a low-fat diet on body weight and cardiovascular risk factors. I was able to read only the ABSTRACT, as full access cost $29.95.
The study participants were randomly selected to be placed in one of two groups and had no restrictions on calories. They were also told to make no changes in physical activity. The target for the low-carb group was to eat less than 40 grams of carbohydrate a day. The target for the low-fat group was to eat less than 30% of daily energy intake from total fat and less than 7% from saturated fat. Both groups received dietary counseling from an RD and were tested at baseline, three months, six months, and twelve months. About 80% of the participants finished the one-year study.
The CONCLUSION was succinct: just two sentences. The first is declarative and absolute: “The low-carbohydrate diet was more effective for weight loss and cardiovascular risk factor reduction than the low-fat diet.” The second, “Restricting carbohydrates may be an option for persons seeking to lose weight and reduce cardiovascular risk factors,” is prospective and phrased more like an implied suggestion. This may be more palatable to physicians, who have not been trained in nutrition, and to nutrition professionals who, together with physicians, have all been misled.
The results, in layman’s terms, have now been broadcast widely. Andreas Eenfeldt (The Diet Doctor) and Jimmy Moore (Livin’ La Vide Low-Carb) were among the first. But The New York Times, The Wall Street Journal, National Public Radio, Time Magazine, CBS News, and the Washington Post, were all quick to follow. The NYT’s summarized it thus:
● Triglycerides – the type of fat that circulates in your blood – “plunged” on the low-carb diet.
● HDL – the so-called “good” cholesterol – rose more sharply than it did for people on the low-fat diet.
● Total Cholesterol/HDL ratio – an important maker of heart disease risk – improved.
● Chronic systemic inflammation – as measured by hs-CRP (C-reactive protein) also “plunged.”
● Blood pressure, total cholesterol and LDL, the “bad" cholesterol, showed little change in both groups.
The NYT article was clearly open-minded and its view of the results positive. A professor of cardiology at McGill University in Montreal who was not associated with the study was quoted as saying that the decrease in [heart disease] risk on the low-carbohydrate diet “should translate into a substantial benefit.” He added,
“One important predictor of heart disease that the study did not assess was the relative size and number of LDL particles in the bloodstream. Two people can have the same overall LDL concentration, but very different levels of risk depending on whether they have a lot of small, dense LDL particles or a small number of large and fluffy particles.”
In contrast to the very well reported and balanced story in the New York Times, the Fox News Channel had a cardiologist on their “Fox and Friends” program who failed to mention, in terms of heart disease risk, all the clearly beneficial primary outcomes of the trial, including the 5 bullets above. He did, however, begrudgingly acknowledge, it seemed to me with genuine surprise, that Total Cholesterol and LDL (the so-called “bad” cholesterol) stayed about the same for people in each group. That was no surprise to me. Personally, I have seen all the listed cardiovascular risk benefits and more. In the course of a few years, I also managed to lose a tremendous amount of weight (170 pounds).
Maybe the more conservative Fox News Network was interviewing a more conservative cardiologist. Frankly, it seems to me that he (and most of the conservative medical establishment) has plaque on the brain, not in their arteries.