If it weren’t for the last minute, nothing would ever get done.
So it goes with my CME (Continuing Medical Education), a rather boring venture most times. That is, until I discover a hidden gem . . .
Nearing the end of another 3-year cycle of reporting CME, I’ve been working to complete some journal quizzes before the end of the year. I was reading an article summarizing the top research studies of 2014 that were relevant to primary care physicians and was pleasantly surprised to discover a particular study cited in regards to weight loss.
Here’s a little blurb from the article about this particular study (PDF of study can be accessed here):
More than 40 years ago, Dr. Robert Atkins wrote his first book advocating for a low-carbohydrate diet to cause and sustain weight loss. This study (of mostly women) found that a low-carbohydrate diet—though not as severe a diet as the Atkins approach—caused an average 3.5 kg (7.7 lb) greater weight loss than a low-fat diet. Both diet approaches were undertaken without any caloric restriction; in other words, these were low-carbohydrate and low-fat, not low-calorie, diets.
The 148 participants were volunteers from the general public: 88% were women and 50% were black. They were randomized, concealed allocation uncertain, to a diet of fewer than 40 g carbohydrates per day (the Atkins diet suggests fewer than 20 g/day) or a diet aimed to keep fat to less than 30% of daily energy intake, which is in line with the diet recommended by the National Cholesterol Education Program in the United States. Neither diet included a specific calorie goal. Participants in both groups received significant counseling consisting of individual weekly sessions with a dietitian for the first 4 weeks followed by small-group counseling sessions every other week for the next 5 months. At 12 months, the low-carb diet group lost an average 3.5 kg more than the low-fat diet group (-5.3 kg vs -1.8 kg). They also had greater reductions in fat mass and higher lean mass gains. Though total cholesterol levels did not markedly change in either group, high-density lipoprotein levels increased significantly more in the low-carb group and triglyceride levels decreased significantly more in that group, as well. Blood pressure, glucose levels, and insulin levels were not different between the groups.
Am Fam Physician. 2015 Sep 1;92(5):377-383.
In addition to the (1) increased weight loss, (2) greater reductions in fat mass, and (3) higher lean mass gains, there was also a (4) significantly greater increase in HDL cholesterol levels in the low-carbohydrate intervention group. Can you lose weight on a low-fat diet? Of course you can, but you’ll likely lose more weight on a low-carbohydrate diet . . . AND improve the markers of metabolic syndrome (HDL cholesterol, triglycerides, glucose, waist circumference, blood pressure).
There are several randomized trials demonstrating the superiority of low-carbohydrate diets over other diets for achieving weight loss. Since carbohydrates stimulate an increased insulin response, and insulin drives weight gain (stores excess energy as fat), it’s an intuitive finding based on basic physiology.
Why, then, is this reference a big deal? Glad you asked.
It’s a big deal because health care is on the verge of a rude awakening.
Obesity is skyrocketing and yet the dietary advice stays the same year after year (actually on a 5-year plan – to be updated this month!). The conventional wisdom of weight loss is that decreasing calorie intake results in weight loss, and that decreasing the amount of fat one eats is preferred because fat contains the most calories per mass (9 Cal/gm for fat vs. 4 Cal/gm for protein and carbohydrates) and because fat is [wrongly] blamed for cardiovascular disease, etc.
But obviously, this dietary advice is not working. Even if the proponents of this diet want to allege that people continue to gain weight because they simply don’t adhere to the advice, then the advice still doesn’t work because people don’t want to follow it. No matter how you look at it, the current dietary guidelines have not improved our collective health.
The changing face of medicine
Simply publishing this reference in a journal that is distributed in print to nearly 180,000 physicians in the US is a step in the right direction towards overturning the bad nutritional information that those 180,000 physicians were taught in medical school. Medicine is driven more and more by evidence. There is an ever-growing application of medicine known as Evidence-Based Medicine, formed out of necessity when it was realized that many procedures routinely offered and performed on patients were inappropriate even by the standards of the expert physicians in the field. (JAMA. 1987 Nov 13;258(18):2543-7. )
The evidence cited above demonstrating significantly greater weight loss with a low-carbohydrate diet than a low-fat diet should be offered to patients as a recommendation based on a scientific, randomized trial – far superior to the traditional committee opinion or weak correlational studies, which were felt to be good enough for the current dietary guidelines (and your health). With luck, more and more primary care physicians will encounter well-designed research studies like this, whether they’re leisurely browsing through the print journal or are chipping away at their CME requirements online at the last minute.
The impending collapse of health care can be prevented
In terms of nutrition, it appears that the government and the professional medical associations are also waiting until the last minute. They have no sense of urgency to replace the current dietary guidelines with evidence-based guidelines, but I surmise that they will just before the collapse of health care. The expense of managing the rapidly growing epidemic of obesity, diabetes, and the associated cardiovascular disease as well as other complications (think bypass surgery or dialysis is cheap??) will eventually be crippling to health care and will force a dramatic change. Impending collapse of the health care system might be the only catalyst to overturn the pitifully unscientific nutrition guidelines that are being driven more by money and politics than by real science.
Finishing CME requirements is one thing, but when it comes to the health of a nation (and world), procrastination is not an option.