Eating a diet low in carbohydrates and high in protein and fat, including red meat, butter, cheese and eggs, made news recently when both The New York Times and Time magazine featured articles reporting study results that show eating some long-vilified foods is actually beneficial. The decades-old philosophy that eating fat creates fat in the body has vocal proponents, including the government’s dietary guidelines. But others (those who believe there are beneficial chemical reactions that take place in the body by lowering carbohydrate consumption and increasing proteins and fats) are glad their practices are gaining credibility. We spoke to two local doctors who both agree and disagree about how justified all the recent hype really is.
Angela Tran, D.O., owner of Med-Fit Weight Loss in Stapleton, is board-certified in internal medicine and is a member of the American Society of Bariatric Physicians. She isn’t surprised by the findings of the studies and feels the attention has been a long time coming. She recounts the inception of the belief, in the 1970s, that fat was a significant factor for heart disease. “Small trials were done, a lot of people were having heart attacks, and heart disease and medications were created to treat cholesterol. Along the way, even though these trials were small, the country said ‘We’re going to correlate that fat is a culprit for heart disease,’” says Tran. Subsequent media attention, development of the food pyramid, and the American Heart Association saying that fat was something to be concerned about, created the birth of low-fat guidelines.
“Then the food industry comes along to follow the guidelines and makes things low fat,” says Tran. “However, fat plays an important role in our bodies. Not only does it transport hormones and vitamins and some other things we need for our cells, it contributes to the fullness signal and satisfaction. So when you take fat out of foods, you are actually hungrier. Our bodies have had to adapt, but we haven’t adapted well in processing carbs.”
James O. Hill, Ph.D., professor of pediatrics and medicine at the University of Colorado School of Medicine and executive director, Anschutz Health and Wellness Center, feels people should be wary of the attention being given to the study. He says the day after the higher protein and fat, lower carb study was released, the results of a meta-analysis (a study of other studies) found no significant difference in weight loss among more than 7,000 people on different name-brand diets, including high-protein, low- fat, and moderation diets. “There are dozens of other studies, some that find the same thing and some find the opposite, which is why you cannot go with one single study,” cautions Hill.
“Any diet you follow will allow you to lose weight,” he says. “There are some people who follow a low- carb diet and do very well, but for most people, that’s difficult to do if you increase your physical activity. Carbohydrates are really the best fuel for physical activity. You don’t need very many carbs if you’re sedentary, but once you get active, you need a lot,” he says. “Saying everyone should eat a low-carb or low-fat diet is just absolutely silly unless you look at the other components of the diet and physical activity.” Hill feels the recommended exercise guidelines of 30 minutes a day, 5 times per week should be considered minimal and that more movement should be added throughout the day—from taking breaks from sitting to using walking and cycling as transportation methods.
Dr. Tran agrees that diets aren’t one-size-fits-all. “The low-fat diet is certainly beneficial for those who have gastrointestinal issues or problems with the liver, gallbladder and pancreas because these particular patients don’t absorb or process fat well,” she says. She would also not put an athlete on a low-carb diet because they need carbs for performance due to their higher metabolic demands. “The typical person who really benefits from low carb is someone who has insulin-resistant conditions such as diabetes or pre-diabetes,” says Tran.
Dr. Hill and Dr. Tran’s discussion of calories shows some of the differences in their beliefs.
Hill says, “There’s never been an indication that people who were fed an equal number of calories, where you knew they were equal, that they got a difference in weight. If you know they are taking in the same number of calories, it doesn’t matter if those come from fat, carb or protein, you’re going to burn them all. Your body needs them. When you’re eating less than you burn, a calorie is a calorie. You’ll find people who disagree with that but I have seen no data that would contradict that point.
“If you don’t carefully control calories, then anything can happen depending on hunger, ease of following the diet, etc. And that’s where the confusion comes in and that’s where sometimes you find low carbs better and sometimes you find low fats better and sometimes you find no difference . . . . When you get a hundred or so (in a study), you can get differences, but once you now get over 7,000 people, what you’re seeing (in the literature) is, overall, there’s no difference (in weight loss on different diets).”
Dr. Tran says, “It’s not about the quantity of calories, it’s the quality of the calories and not so much about just creating a deficit. That’s the unique thing about the low-carb diet, you’re actually not counting calories. You’re eating really good quality foods in the right portions and your body’s going to process it much more efficiently.” Tran adds, “The low-carb approach is what we (the American Society of Bariatric Physicians) have used in our practices across the country.”
Tran explains that a diet lower in carbs and higher in protein and fats works because carbs break down into blood sugar, which is controlled by the hormone insulin. Blood sugar goes to muscle for energy use but leftover blood sugar gets sent to the liver, which converts it into fat. “That’s what causes you to increase fat storage and gain weight,” says Tran, adding that if the amount of carbs is lowered to the right amount to feed muscle, there is none left over to be turned to fat. “Now you’re burning fat for energy and storing less, which equals weight loss,” she says.
To help guide patients toward a balance of protein, fat and carbs, Tran recommends consuming a daily average of 25 percent carbs, 40–50 percent protein and the remaining 25–35 percent fat. For those who prefer an easy way to visualize the division, Tran says a serving of protein should be the size of the palm of your hand, vegetables the size of a tennis ball, and carbs half a tennis ball.
One thing both doctors can agree on is that obesity is on the rise and is considered a disease, although only recognized as such by the American Medical Association in 2012, which Tran finds frustrating. “We know it’s a disease because of all the other medical conditions that have come along with it,” she says. “We’re slowly coming along. We still have a long ways to go.”