New Calorie Diet Study

Article by Greg Bonney.

A new study by Harvard has claimed that "… eating fewer calories leads to weight loss, regardless of where those calories come from," according to a Harvard School of Public Health article by Todd Datz dated February 25, 2009 (http://www.harvardscience.harvard.edu/medicine-health/articles/weight-loss-bottom-line-fewer-calories). Okay, so what? More importantly, the subtitle of the article claims "Carbohydrate, protein, or fat content doesn’t play a key role" which goes way beyond what the study actually concluded.

This study is being reported all over the news and is very interesting until you read the actual details of the study. In particular, the fact that the 4 groups of subjects were on diets ranging from 35% carbohydrates to 65% carbohydrates, so none of them were really low carb diets.

According to http://wilstar.com/lowcarb/: "There are many different versions of the low-carb diet, such as Dr. Atkins New Diet Revolution, Protein Power, Neanderthin, The Carbohydrate Addict's Lifestyle Plan, Life Without Bread, and others. All of them, however, have one thing in common — a very strict reduction in the consumption of carbohydrates. Most low-carb diets replace carbohydrates with fats and proteins. Although diets vary in their recommendations, as a general rule, a low-carb diet is synonymous with a high-fat and moderate protein diet. Those on a low-carb diet should get at least 60 to 70 percent of their daily calorie intake from fat. Carbohydrates should make up less than 10 percent, and in some cases, less than 5 percent of your daily calorie intake."

Even the more modest diet by Dr. Sears known as The Zone has a ratio of protein to carbohydrate to fat of 40:30:30, which is lower in carbohydrates than any of the four groups in the Harvard study.

On NPR Talk of the Nation Science Friday February 27, 2009, Dr. Frank Sacks the head researcher in the Harvard study admitted, "The highest carb [diet] didn't really reduce insulin levels." Sacks didn't seem to think this was an issue, because nobody in his study was diabetic. Hello! Low carb diets are all about lowering insulin levels! It is the lower insulin that is supposed to super-charge fat burning processes in the body and decrease risks of all kinds of health problems.

What this study did was to compare four different relatively high carbohydrate diets and then allowed the science reporters to jump to the conclusion that one of them was a low carb diet. You might even think it was a natural assumption, because otherwise what's the point of the study? I really have no clue unless it is to make money for the researchers.

Fortunately, I am not alone in noticing this flaw. Jimmy Moore of examiner.com (http://www.examiner.com/x-867-LowCarb-Lifestyle-Examiner) wrote, "Each of the diet plans used in this study were forced to comply with the 'heart healthy' guidelines that restricted saturated fat calorie intake to less than 8 percent of total calories, generous portions of fruits, vegetables and whole grains, and a minimum of 20g of fiber daily. The template for the diets was the infamous DASH (Dietary Approaches to Stop Hypertension) diet rather than any of the more popular diet books over the past decade, including Atkins and Dr. Arthur Agatston’s South Beach Diet." You really should read Jimmy's article, because it has some great quotes from experts, but I think you get the point.

Now let's compare this to a diet study that actually collected useful information.

This information is from an article by Clarence Bass (http://www.cbass.com/LowCarb.htm), describing a diet study that was featured as "the headline on page D1 of The Wall Street Journal: 'Study Fuels Low-Fat vs. Low-Carb Debate.'" "The 2-year study, funded by the Robert Atkins foundation and reported in the July 17, 2008, New England Journal of Medicine, randomly assigned 322 moderately obese subjects into one of three diets: low-fat, Mediterranean, and low-carb. Calories were restricted in the first two diets, while the low-carb diet limited carbohydrate intake to 20 grams per day for two months, and then gradually increased to120 grams. All three groups ended up eating about the same number of calories."

Bass goes on to say, "The low-carb group lost an average of 10.3 pounds, the Mediterranean group lost 10 pounds, and the low-fat group lost 6.5 pounds. The low-carb group reduced the ratio of total cholesterol to HDL ='good' cholesterol by 20%, compared to 16% in the Mediterranean group and 12% in the low-fat group. (Low ratio is better.)Levels of LDL “bad” cholesterol did not change significantly within the groups. Harmful triglycerides decreased significantly in the low-carb group compared to the low-fat group (24mg vs. to 3mg). Finally, those on the Mediterranean diet (<35% fat, rich in vegetables, poultry and fish instead of red meat) did best in controlling blood sugar levels."

This study was conducted by Ben-Gurion University of the Negev in Israel. According to the Wall Street Journal article by William M. Bulkeley (which you can read at http://www.aabgu.org/media-center/headlines/study-fuels-diet-debate.html), "The study, which tracked 322 Israelis for two years, surprisingly found that a low-carb diet, often associated in the U.S. with high levels of meat consumption — was better than a low-fat diet in boosting blood levels of 'good' cholesterol, or high-density lipoproteins associated with cardiovascular health benefits. It also determined that the Mediterranean diet, which includes wine, olive oil, whole grains and fruits, was better than the low-fat diet in controlling glucose levels."

So, when comparing a real low carb diet to other diets, there really are differences among different diets even in the same calorie range.

You may still conclude, as Clarence Bass did, that a low carb diet is not right for you. He says, "Personally, I would not choose the low-carb approach. I tried it many years ago and resolved never to do it again. I felt tired and couldn’t think properly; see my book Ripped for full details. As an athlete, my muscles and brain need carbohydrates (glucose) to function properly." However, that's anecdotal, not scientific and brings up many more questions (hopefully answered in his book?). Which low carb diet did he try? How low carb is low carb? Did he try consuming more carbs just before or just after exercise and limiting the rest of the day? How long was he on the diet?

I admit the induction phase of Atkins is tough. You may feel tired and get headaches for few days as your body is adjusting, especially if you try to give up caffeine at the same time. After the induction phase, you can increase carbs. Other low carb diets are less drastic than Atkins and might be less of a problem. Also, timing when you consume carbs can help. However, these are all details that don't speak to the basic questions that they tried to answer in these studies.

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