Fad Diets: What Really Works

UW Health Registered Dietitians explain why fad diets don't workYou may have heard about the Cabbage Soup Diet, the Atkins Diet and other fad diets that promote rapid weight loss. But such fads offer only short-term quick fixes, are often developed by people with no health or nutritional background, and can even be harmful.


Fad diets lead to weight loss because they restrict food choices and lead to eating fewer calories than are expended. Because weight loss tends to be rapid, muscle and water are lost in addition to fat. Since these diets are too restrictive, they cannot be maintained. Once people go off the diet and begin to eat normally again, the weight they have lost is usually gained back as fat.


The following tips will help you with successful and sustainable weight loss:

  • Slow weight loss is the key to weight maintenance. Aim to lose no more than 1/2 to one pound per week.
  • Eat at least three meals per day. Eat breakfast as soon as you wake in the morning in order to boost your metabolism.
  • Exercise is essential for health. Find physical activities you enjoy and aim for 30-60 minutes of physical activity daily for at least five days per week.
  • Avoid diets that tell you to limit entire food groups. You need to maintain a healthy balance of all food groups because each food group provides essential nutrients. Be sure to include complex carbohydrates like whole grains, colorful fruits and vegetables, lean meats and dairy products, and healthy fats such as omega-3 fatty acids from fish and monounsaturated fats from avocados, nuts, olives and olive oil.
  • Avoid diets that claim certain foods will help you to lose weight.
  • Eating specific foods at certain times of the day or specific combinations of food have not been shown to help with weight loss.

Rigid meal plans are likely not sustainable. Ask yourself, "Can I eat this way for the rest of my life?" If the answer is no, it is not the right meal plan for you.


What's a Portion?


Successful weight maintenance needs to be something you can maintain lifelong. When weight is lost while following a rigid and restrictive plan, the weight is often regained when the diet is stopped. Furthermore, it is extremely important not only to pay attention to the foods you eat, but to portion size as well.


Many people eat portions that are too large. Here are some things to keep in mind: 

  • A cup of fruit should be no larger than your fist
  • One ounce of meat or cheese is the size of your thumb from base to tip
  • Three ounces of meat, fish or poultry is an appropriate serving size. It’s the size of your palm or a deck of cards.
  • One to two ounces of nuts would fit in your cupped hand
  • Serve meals on salad plates instead of large dinner plates
  • Pre-portion snack foods into sandwich bags
  • Restaurant portions are often too large. Split an entrée with a friend or take half of your entrée home.
  • Choose the small size at fast-food restaurants. Never ask for the super-size portion.
  • When eating out, fill up on salads, fruits and vegetables first. Eat smaller portions of high-fat foods and desserts.



The following information was provided by Laura Isaacson, MS, RD, CNSC, and Kelly Nuckolls, MS, RD. UW Health's Registered Dietitians provide accurate, evidence-based nutrition information that promotes health and wellness to empower individuals to make healthy lifestyle changes that will enhance their health. Recommendations may vary based on your individual health history. For a personalized nutrition plan contact UW Health to schedule an appointment with a Registered Dietitian. For more nutrition information, visit the Nutrition and Health Library.