The debate between whether low-fat, plant-based diets or high-fat, low carb diets work better for weight loss has become increasingly heated. Now several new studies indicate that foods recommended for high fat diets, including butter, cream and full-fat milk, can boost weight loss and keep you lean, reported NPR on Feb. 12.
Swedish researchers have discovered that middle-aged men who consume high-fat milk, butter and cream are significantly less likely to become obese than those who avoided high-fat dairy. Their study contrasted two groups of men during a 12-year period, and those who followed the higher fat diet were more likely to stay lean.
"I would say it's counter-intuitive," says Greg Miller, executive vice president of the National Dairy Council, at the results showing that high-fat dairy kept the men slimmer.
In another study, researchers analyzed a hypothesis that high-fat dairy foods contribute to obesity and heart disease risk. However, after a meta-analysis of 16 observational studies, the scientists discovered that high-fat dairy was linked to a reduced risk of obesity.
"We continue to see more and more data coming out [finding that] consumption of whole-milk dairy products is associated with reduced body fat," says Miller.
The reason for this seemingly contradictory diet link? Some experts cite the satiety factor. In other words, consuming food high in fat, such as butter, fills you up, so that you eat less. They also refer to this factor in the success of low-carb diets.
However, not enough is known to develop a final conclusion.
"There may be bio-active substances in the milk fat that may be altering our metabolism in a way that helps us utilize the fat and burn it for energy, rather than storing it in our bodies," Miller theorizes.
Other studies show that the association between higher dairy fat and lower body weight holds true for children as well. One study revealed that children who drank low-fat rather than full-fat milk gained more weight.
"It really surprised us," study author Mark DeBoer, a pediatrician at the University of Virginia, told NPR.
However, some experts are not surprised. Dr. David Perlmutter, for example, recently released a book advocating high fat, low carb diets for weight loss and for protection against conditions ranging from dementia to depression: "Grain Brain: The Surprising Truth about Wheat, Carbs, and Sugar--Your Brain's Silent Killers" (click for details).
And science writer and researcher Gary Taubes has been contending for years that carbohydrates are the enemy, not saturated fat, in his bestsellers such as "Why We Get Fat: And What to Do About It" and "Good Calories, Bad Calories: Fats, Carbs, and the Controversial Science of Diet and Health."
But the debate about the merits of high fat, low carb diets hasn't died down. Dr. David Katz recently attacked Taubes in a Huffington Post editorial, defending low fat diets. His view: Americans have misinterpreted and misused the concept of low-fat diets by chomping up anything labeled fat-free, regardless of the calorie content.
"The advice to cut fat was intended to direct us to the naturally low-fat foods that existed at the time, namely vegetables, fruits, beans, lentils, whole grains," says Katz, whose most recent book is "Disease-Proof: The Remarkable Truth About What Makes Us Well."
Also taking up the argument against high fat diets and arguing for low-fat plant-based diets: John McDougall, M.D., author of "The Starch Solution: Eat the Foods You Love, Regain Your Health, and Lose the Weight for Good" (click for details).
McDougall authored a blog for the Forks Over Knives community, entitled "The Smoke and Mirrors Behind Wheat Belly and Grain Brain."
In it, he took up his own forks and knives against both "Grain Brain" and "Wheat Belly: Lose the Wheat, Lose the Weight, and Find Your Path Back to Health."
Within their pages you learn that all starchy foods, including rice, corn, and potatoes—the traditional foods consumed by billions of people throughout human history—are now unhealthy and must be minimized or, better yet, avoided altogether.
If you believe these authors, then what is left to eat in order to meet your energy requirements? Meat, dairy, fish, and eggs (the original Atkins Diet).
He expands from there, citing studies that high protein, high fat diets are harmful to the health. And although McDougall does concede that "low-carbohydrate diets can cause weight loss," he contends that his approach is better for a long, healthy life.
But has enough evidence been developed to compare adequately the long-term weight loss and health benefits of a high fat, low carb diet versus low-fat plant-based or "starch solution" plan?
As Gary Taubes writes on his Web site, we still need "rigorous, well-controlled experiments targeted at resolving unambiguously many of the outstanding nutrition controversies — to answer the question definitively of what constitutes a healthy diet."