Keto Dieting Risks

When you follow a keto diet, you severely limit carbohydrates, eating only 20 to 30 grams of carbs daily (about the amount in a medium-sized banana). You eat primarily meat (protein), fish, shellfish and nonstarchy vegetables. You also eat plenty of fat, such as olive oil, butter and coconut oil. The body then breaks down the fat into molecules called ketones, which serve as an alternative fuel for the brain and muscles. It typically takes a few days to enter this state of ketosis.

Ketones are produced by the liver, which breaks down fat in response to low blood insulin levels. When you restrict carbs, your body uses the ketones for energy instead of glucose. Some studies have shown that ketogenic diets can help with epilepsy by reducing seizures.

But it isn’t an ideal long-term solution for most people. The high-fat, low-carb approach can lead to nutrient deficiencies, especially if you rely on processed or packaged foods, says Dr. Condon. That may include a lack of fiber, vitamin C, folate, calcium, magnesium and potassium, which can cause bloating, constipation and fatigue, among other symptoms.

Other risks include short-term weight loss and a potential for plateaus and even weight regain. The keto diet can also lower good cholesterol and raise triglycerides, leading to heart disease risk factors, say experts. They recommend getting a baseline cholesterol and triglyceride blood test before starting the keto diet. Then after three to six months, you can see whether your numbers have improved or not.