What Are the Symptoms of Food Intolerance?

Doubling over with abdominal pain or running for the bathroom after every meal can be painful, annoying and embarrassing. Food intolerance can be less severe than food allergies, but it too can be inconvenient and troublesome. It's important to know what the symptoms of food intolerance are in order to stop them in their tracks. 

The differences between food allergies and food intolerances aren't exactly black and white . The symptoms may be similar but tend to occur at different times and levels of intensity. A food allergy is an autoimmune response, whereas food intolerance is a digestive system problem. 

Symptoms of food intolerance include: 

  • nausea;
  • stomach pain;
  • gas;
  • cramps;
  • bloating;
  • vomiting;
  • diarrhea; and
  • headaches. 

Health expert Dr. Andrew Weil writes, "Food intolerances are often highly individualized and mysterious" and are "due to physical or emotional stress or exposure to environmental toxins rather than a reaction to the foods themselves." He added that intolerance is not a true allergy. Food intolerance will not show up in allergy tests. But the negative result does not mean the food agrees with your digestive system. 

Food intolerance is more common than food allergies, and the only real way to tell if you have food intolerance is by trial and error to see which foods cause you to feel sick. When you eliminate the problematic food from your diet, symptoms should disappear. 

WebMD describes one difference between a food tolerance and a food allergy as how quickly the symptoms set in, as well as the severity of food intolerance symptoms. An allergy can be life threatening in severe cases, and the symptoms happen suddenly after consuming the problematic food. The effect is less severe for a food intolerance and after eating the problem food, the onset is more gradual. Food intolerance symptoms may appear after overeating. 


 

Common Sources of Food Intolerance 

Common triggers among both allergies and food intolerances are nuts, fish, dairy products, eggs, soy and wheat. Syrup, corn and fruit sugar (fructose) also can be problematic. Fructose intolerance and lactose intolerance are among the most prevalent and the easiest to diagnose. Avoiding these foods is one way to minimize the painful symptoms associated with the condition. 

With 7 to 20 percent of adults experiencing symptoms like irritable bowel syndrome, researchers in the March 2011 issue of Gastroenterology Clinics of North America noted that many people with IBS report symptoms shortly after eating. They report that as many as 93 percent of patients fell ill within three hours of eating, citing another study. The study found that people who experience food intolerance symptoms often receive the wrong treatment when what they really need is dietary intervention and counseling. 

The best way to identify the problem is to journal about your diet and reactions after eating certain foods. By tracking how you feel, you may be able to see a pattern and learn which foods cause you trouble. When that food is removed from your diet completely, you should feel better and lose the symptoms associated with food intolerance. 


 

Learn how to read food labels and understand code words that mean the same thing as the food that causes you gas, pain and bloating. Ingredient lists aren't always written clearly enough to make it obvious that the item contains the food to which you are sensitive or intolerant. It is up to you to be your own advocate and know what is in everything you eat. Only then can you avoid the foods that make you sick so you can prevent the symptoms of food intolerance. 

The elimination diet is a good method for identifying and treating the symptoms of food intolerance. Removing certain foods from your diet for a period of a couple of weeks and then slowly adding them back in while tracking your reaction to them is a good way to find out what foods cause digestive problems. Those you can eat without feeling sick can be added back in, while you avoid problematic foods to keep from experiencing symptoms after eating. You may start by removing: 

  • gluten;
  • wheat;
  • dairy;
  • soy;
  • eggs; and
  • coffee. 

While the diet may seem drastic, you need to stick with it for just two weeks to get the other foods out of your system. When you slowly add one or two items back in, it will be clear whether or not they are the problem. Concentrate on recognizing and controlling what you eat for an accurate test. You may work with a dietitian to create a meal plan you can follow that allows you to test your intolerance for certain foods while still getting the nutrients you need. Also consult your doctor if you have any health problems to avoid eliminating essential nutrients from your diet. 

The whole process of adding food or groups of food back into your diet can take up to six weeks because each group needs to be added back in slowly and monitored for several days before another food can be added. Watch the symptoms listed above as you rule out foods. 

By the time you complete the elimination method, you should have a good idea of the foods that cause stomach pain, diarrhea and other symptoms of food intolerance. Once you do this, you will reduce the number of incidents after eating. There will be no more embarrassing moments of being gassy or making a mad dash for the restroom. You may have to avoid a food group, but the payoff is a feeling you'll definitely be able to stomach.