Swimsuit season is here and you may have noticed that you have a few pounds that have crept up over the sedentary winter months. Tempted by some of the diet trends circulating on Instagram, Tiktok and other media? I’m often asked my opinion on these trendy diets. One thing I’ve learned over the last 30 years being a dietitian: most diets work for weight loss, but many don’t work for the long term. If you don’t work on changing your behaviors, those behaviors will come back and usually you’ll regain some weight. The problem is some trendy diets can even be harmful to your long-term health.

Ketogenic (Keto) Diet

You probably know at least a handful of people who rave about the keto diet. They’ve lost weight, have better focus and may even sleep better. Even some dietitians swear by it! In my opinion, there are some practical and health issues to consider with Keto diets:

  • May be difficult to follow over the long term
  • Keto “flu” is not pleasant
  • Is no more effective than a regular weight loss diet with similar calorie level
  • It cuts several whole food groups out of your diet, which are anti-inflammatory and cancer-fighting and good for blood pressure.
  • Research has shown that this diet may decrease blood sugar, but the effect is short term. 
  • Keto diets generally increase saturated fat, cholesterol and animal protein, which are linked with insulin resistance and oxidative stress. LDL cholesterol has also been shown to increase significantly, which is associated with an increased risk of heart disease.
Intermittent Fasting (Time Restrictive Feeding)

This diet has also gained a lot of traction in the last few years. Positives for some people is not having to think about “what” to eat, just “when” to eat. Some highlights of the diet:

  • Easier to follow long term than Keto
  • Doesn’t cut out whole food groups
  • Because it doesn’t focus on foods to eat more of or limit, it may not encourage you to eat any healthier.
  • Research on Time Restricted Feeding has shown promise for its effectiveness for weight loss, reducing blood pressure, body and abdominal fat and reducing the risk of factors for metabolic syndrome, diabetes and cardiovascular disease.
  • However, a recent study looking at the eating habits of 24,000 American adults found that skipping meals can lead to an early death. Skipping breakfast was linked with death from heart disease, and skipping lunch or dinner was linked to a higher risk of all cause death. But this study, which did adjust for smoking, alcohol and calorie intake and activity level was an observational study, so does not prove causality.
Detox and Cleanse Diets
  • Detox and cleanse diets promise big weight loss and removal of toxins in your body through fasting, drinking only juices, adding herbs, laxatives and even colon cleanses. The truth is some of these practices can be dangerous, including causing dehydration and electrolyte imbalances which can affect the heart and muscles. 
  • Beware of diets that contain only fruits and vegetables. When you don’t eat enough protein while losing weight, part of your weight loss will be muscle. Muscle uses more energy than fat, so muscle loss should be avoided for multiple reasons!
  • There is very little scientific basis for detox or cleanse diets, though some well-known celebrities swear by them. Your liver, kidneys, lungs and skin are detoxing your body 24/7. Supporting them by eating plenty of fruits, veggies and less processed foods, getting enough sleep, drinking plenty of water, and moderating alcohol intake are the most effective ways to detox. Finally, exercise enough to work up a sweat; sweating actually helps your body get rid of heavy metals like lead and arsenic.


Intermittent Fasting, Longevity and Disease

Ketogenic Diets and Chronic Disease: Weighing the Benefits Against the Risks

The Goop Lab Experiments with Viewers Credulity

Dr. Oz’s “Two Day Holiday Detox “Should be Flushed