Low-fat diets are not effective. That’s the conclusion of the newest research comparing low-fat diets to weight loss plans that are higher in fat and protein but lower in carbohydrates, reports Science Daily.
Although many clinical trials have been conducted to determine whether low-fat diets are best for weight loss, the results previously were often contradictory. Now, a new study that lasted longer than many of the others revealed that slashing those tasty, high-fat foods such as cheese, steak, and butter as needed for a low-fat diet had no more benefits than eating a diet higher in fat when it comes to weight loss.
To conduct the new study, researchers from Brigham and Women’s Hospital (BWH) and the Harvard T.H. Chan School of Public Health (HSPH) analyzed data from clinical trials that focused on low-fat diets. Given that the prevailing wisdom was that dieters must reduce fat to win at weight loss, the researchers sought to discover whether it was fact or fiction.
“Despite the pervasive dogma that one needs to cut fat from their diet in order to lose weight, the existing scientific evidence does not support low-fat diets over other dietary interventions for long-term weight loss,” said Deirdre Tobias, ScD, a researcher in the Division of Preventive Medicine at BWH. “In fact, we did not find evidence that is particularly supportive of any specific proportion of calories from fat for meaningful long-term weight loss.”
Therefore, said Tobias, it’s important to look at issues such as portion sizes and what really helps dieters to stick to a diet. The researchers’ meta analysis included nearly 70,000 participants and 53 separate studies, with the focus on diets that were longer than 12 months.
Although the average weight loss was six pounds for all types of diets, when researchers followed up after a year, those on low-carb diets had succeeded in shedding an additional two-and-a-half pounds.
With some describing both diabetes and obesity as epidemics, a diet study comparing the American Diabetes Association food plan to a low-carb ketogenic diet provided some food for thought, points out Dr. William Lagakos of Calories Proper.
Lagakos, who has a Ph.D. in Nutritional Biochemistry and Physiology with a focus on obesity, inflammation, and insulin resistance, notes that this trial contrasted a moderate carb diet to an extremely low carb diet in those who were overweight or obese and had type 2 diabetes.
“[The study] was confirmation of a phenomenon that is starting to become well-known, and soon to be the status quo. That is, advising an obese diabetic patient to reduce their carb intake consistently produces better results than advising them to follow a low fat, calorie restricted diet….The most important finding of this study…: 7 out of 11 keto dieters (64%) were able to reduce their anti-diabetic medications, whereas only 2 out of 13 low fat dieters did (15%).”
But, that’s not the only evidence that low-fat diets are not effective, while low-carb diets are. More than 20 studies in the last decade have shown that low carb diets trump when it comes to weight loss. These food plans, whether you go with the unprocessed food Paleo version, the higher fat Atkins diet, a plant-based vegan or vegetarian diet, or do-it-yourself low carb diet, eliminate the need to count calories while cutting down on hunger so that you eat fewer calories without stressing about it, according to Eco Watch.
In addition to weight loss, low-carb diets can boost good cholesterol (HDL) and help combat belly fat. Dieters who cut carbohydrates, such as bread and pasta, may also benefit from reductions in their blood sugar levels and blood pressure. Low-carb diets also may be helpful for conditions ranging from type 2 diabetes to obesity.
For those on the Paleo or Atkins diet — both of which allow meat, fish, and poultry — utilizing the new data showing that low-carb diets work most effectively can be easy to implement. But, even vegans and vegetarians can benefit by understanding how to cut carbohydrates while adhering to a plant-based diet.
Vegetarians who consume eggs and dairy should make sure that they’re eating versions that are processed without additional sugar. For example, skip that tempting raspberry jelly omelet at your favorite cafe or the sugar-laden carton of yogurt at the store. Grass-fed butter and cheese are other low-carb-friendly additions to a vegetarian low-carb diet.
For vegans who want to try a low-carb diet, remember that tofu, tempeh, and other soy products that do not contain sugar contain protein and fat without excess carbs. Other options include seeds and nuts. Most vegetables also are low in carbohydrates but it’s important to remember to limit your fruit intake, caution experts. For vegans who feel envious of the butter available to vegetarians, consider fats such as coconut oil and extra virgin olive oil.
If you’re perplexed about how, with all this evidence, the prevailing wisdom for decades has been that fat is evil, investigative journalist Nina Teicholz recently answered the question in her ground-breaking book, THE BIG FAT SURPRISE: Why Butter, Meat & Cheese Belong in a Healthy Diet.
In it, Nina traces the history that caused so many health experts to tell their overweight patients to go on low-fat diets, while citing significant evidence that diets higher in protein and fat are best for overall health as well as weight loss.
“I think there’s no doubt that the evidence used to sustain the diet-heart hypothesis has been cherry picked. Large clinical trials have been ignored. In the case of the largest-ever trial to test the hypothesis, the investigators simply didn’t publish the results for 16 years, because apparently they were so disappointed in the way they came out. This is selection bias, or cherry picking, at work,” notes Teicholz on her website.
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