Fad Diets: Lower Weight, Higher Heart Risk?

Fad diets have been around for a while, with newer ones cropping up all the time. “But research shows that some of these diet trends may increase your risk for health problems like cardiovascular disease,” says cardiologist Nidhi Mehta, MD, with LVPG Cardiology–Muhlenberg. The American Heart Association (AHA) recently identified some of the heart-riskiest dietary patterns.

“Proceed with caution if you want to try a new diet.” - Nidhi Mehta, MD

These included the following:

What is it? An eating pattern that emphasizes produce, whole grains and legumes while cutting out oils, meats, fish, nuts and seeds, eggs and dairy. Examples include the Ornish and McDougall diets. To follow a very low-fat diet, less than 15 percent of your total calories needs to come from fat.

What are its heart risks? “This diet limits or forbids some foods that the AHA says are important for heart health, such as fish, nuts and plant oils,” Dr. Mehta says. “Excluding these foods from your diet can increase your risk for heart problems.” And this diet can lead to nutrient deficiencies that are associated with heart disease. If following a low-fat diet, focus on nutrient-dense foods. 

What is it? Short for Paleolithic, this diet encourages loading up on produce, nuts and lean meats while staying away from grains, legumes, oils and dairy.

What are its heart risks? The AHA puts the Paleo diet in its lowest tier of adherence to a heart-healthy diet and says it’s “of strong concern” around heart health. Two other problems: possibly not getting adequate nutrients and lack of fiber.

What is it? A keto, or ketogenic, diet focuses on high fats and low carbs. It emphasizes meats, eggs and full-fat dairy while severely limiting carbohydrates like grains, legumes and most fruits.

What are its heart risks? Another diet classified in the lowest tier by the AHA, keto can lead to the loss of certain plant-based chemicals that are associated with a reduced risk of dying.

The ultimate takeaway? “Proceed with caution if you want to try a new diet,” Dr. Mehta says. “The best path toward weight loss is different for everyone.” Talk with your doctor or clinician about what’s right for you. Try focusing on Mediterranean foods, including fruits, vegetables, grains, olive oil, legumes, nuts, seeds, and fish. Or look into the DASH eating pattern, which can help lower high blood pressure.

For DASH diet information: 

Opens in new tab Go to NIH.gov