How to Try an Elimination Diet

Medically Reviewed by Melinda Ratini, MS, DO on September 28, 2021
3 min read

When you have frequent diarrhea and can’t pinpoint its cause, you may wonder if certain things that you eat cause the problem. Sometimes, it’s easy to guess which foods may be the culprit. One way to find out if your hunch is right is to go on an elimination diet.

An elimination diet isn’t about weight loss. Instead, you do it to find out if skipping certain foods for a while makes a difference to your digestion.

Many foods can act as triggers for diarrhea, but the same ones don’t affect all people the same way, and some aren’t obvious choices to avoid. So you may need to do a bit of testing until you find your problem ingredient.

Elimination diets can help reduce frequent diarrhea that’s caused by a number of chronic health problems, such as:

  • Lactose intolerance
  • Irritable bowel syndrome (IBS)
  • Food allergy or intolerance
  • Gluten intolerance or celiac disease

The first step is to check in with your doctor or a nutritionist. Tell them about your diarrhea and other symptoms.

If they think an elimination diet would help, they’ll let you know which items to take out of your diet, how long to skip them, and how to get all the nutrients you need.

You may have already thought of some items that you suspect are the problem. An expert may be able to point out others that could be part of the problem.

Your doctor knows your health history and may suspect what could be the cause of your diarrhea. If they think that you could have IBS, for example, they may suggest that you rid your diet of certain kinds of fiber. If they think that gluten might be the culprit, they’ll help you rid your diet of all foods that could offend.

Some people who try elimination diets alone make them too drastic, cutting out too many foods at once, which can lead to poor nutrition. You’ll want expert advice to help you stay healthy as you try to find the cause of your diarrhea.

Your doctor or nutritionist can also give you guidelines about how long to wait before you decide that the food you eliminated from your diet was not the problem. Sometimes, your doctor may suggest that you stop eating a certain food for a few weeks. In other cases, they may suggest that you quit for up to 12 weeks or more before trying something else.

When you’re ready to get started:

  1. Decide, with the help of a health expert, what is the most likely food that causes your diarrhea.
  2. Work with your doctor to rid your diet of this food for a set period of weeks and notice how you feel. In a food diary, note everything else that you’re eating. Mention whether or not you have diarrhea or other symptoms.
  3. At the end of the diet, if the food that you’ve stopped eating didn’t fix the problem, add it back into your diet, and quit eating the next food on your list.
  4. Follow the same plan until you find the food that affects your stomach and causes diarrhea.

These items sometimes cause diarrhea in certain people. You may want to eliminate them from your diet, one at a time, starting with the food that seems to be your most likely trigger.

  • Dairy products such as milk or cheese
  • Foods with added fructose (also called high-fructose corn syrup)
  • Wheat and other foods that have gluten
  • Nuts
  • Caffeine (coffee, tea, colas, chocolate)
  • Fatty, fried foods
  • Foods with a “diet” or “sugar-free” on the label

If you have any questions or problems as you go through the process, reach out to your doctor or nutritionist for help or advice.