Can You Lose Weight Eating High-Fat Foods?

The keto diet is the latest weight-loss regimen taking the dieting world by storm. Many are reporting extraordinary results, but is it the best plan for you? We sat down with nutrition expert Dr. Thomas M. Campbell, medical director of the Highland Weight Management & Lifestyle Center, to talk about the pros and cons.

Health Matters: What is the keto diet?

Campbell: The ketogenic diet—or keto diet, as it's commonly known—is a low-carb, moderate protein, high-fat diet. Its purpose is to get the body to burn fats instead of carbohydrates, putting it into a metabolic state known as ketosis.

A few of the foods allowed in the diet include meat, poultry, cheese, eggs, butter, and cream.

Foods not allowed on the diet include certain vegetables including potatoes and beans, fruit, and all foods made from grains.

Health Matters: Why is it so popular?

Campbell: It's basically a way for people to have short-term benefits while eating their favorite foods. People love to hear good things about their bad habits, so communicating that you can lose weight and drop your blood sugar while eating bacon and lots of oil has plenty of appeal. This message is reinforced because the diet works in the short term. Unfortunately, the diet encourages eating super-rich foods, which aren't good for you in the long run.

Health Matters: Does it really help you lose weight?

Campbell: Yes. When you're in ketosis, you are in a fasting-mimicking state. There are a lot of benefits to fasting, which hold true in ketosis as well. Essentially, your body stops using carbs for fuel. You lose weight while your appetite is satisfied. Because you're eliminating the major source of blood glucose in your body, people can see a drop in blood sugar as well. Losing weight can result in lower blood pressure too, so there are some short-term benefits.

The effects of being in ketosis over a long time are largely unknown. But when you get out of ketosis, you're left eating a diet very high in meat and added fats, without the benefits of the fasting-mimicking state. We know that this is a dangerous way to eat long term. The vast majority of research shows this is associated with weight gain, diabetes, heart disease, certain cancers, and premature death.

Health Matters: What are the benefits?

Campbell: People lose weight in the short term. It is quick weight loss eating your favorite foods; that’s the appeal.

Health Matters: What should people watch out for if they choose to do the keto diet?

Campbell: When choosing a diet, you don't want to lose weight at the expense of long-term health, and once you’re out of that ketotic state, eating a diet loaded with meat and fat, long-term health is likely to suffer. In addition, the keto diet can be a risk for anyone with kidney disease. It can provoke kidney stones as well as gallstones and gout.

When you’re starting the diet, some of the initial weight loss is water weight, but you might have an influx of water weight when you start adding carbs again. And of course you can’t tell how much is water from a standard bathroom scale. So while it may be encouraging with the quick weight loss in the beginning, it’s frustrating if you have equally easy, rapid weight gain when you start eating more carbohydrates again. This process can be very demoralizing for people who have tried multiple times to lose weight unsuccessfully.

The one condition that has been scientifically proven to benefit from the keto diet is seizure disorders. Studies have shown, for example, that this diet does work to treat difficult-to-control epilepsy in children.

Thomas M. Campbell, M.D., is a board-certified family physician and medical director of the Highland Weight Management & Lifestyle Center. With his father T. Colin Campbell, PhD, he co-authored "The China Study, The Most Comprehensive Study of Nutrition Ever Conducted and The Startling Implications for Diet, Weight-Loss, and Long-Term Health" and has published a follow-up book, “The Campbell Plan.”