Here's Why Eating Almonds Can Cause Stomach Pain

Almonds are a rich source of protein, vitamin E, fiber and many other nutrients, according to the U.S. Department of Agriculture (USDA). Many people enjoy them as a nutritious snack. However, some find themselves regretting their choice a short time later when a mild to severe stomach ache sets in.

As it turns out, eating a lot of almonds, especially raw almonds, can cause stomach pain for several reasons. Although the reaction is usually temporary and harmless, stomach cramps from almonds can occasionally be symptomatic of a dangerous food allergy or even almond intolerance.

The U.S. National Library of Medicine (NLM) reports that tree nuts such as almonds are one of the "problem foods" that most commonly trigger allergic reactions. Even a mild allergy to almonds can cause gastrointestinal symptoms such as abdominal cramps and pain, nausea, diarrhea and vomiting. If you consistently have stomach pain after eating almonds, it might be a good idea to consult your doctor to rule out the possibility of an almond allergy.

There is no cure for an almond allergy, so you will need to create an elimination diet with your doctor to prevent symptoms from recurring. No matter how much you like almonds, you may have to stop eating these nuts if you develop stomach ache or abdominal cramping every time you eat them.

If you experience serious symptoms after eating almonds — such as severe dizziness or difficulty breathing — contact a doctor right away, because these are symptoms of a life-threatening allergic reaction called anaphylaxis, according to the Centers for Disease Control and Prevention (CDC). This condition can lead to death if not treated.

Many people enjoy eating almonds in their natural state. But the rigid texture of raw almonds can make them difficult for the stomach to break down during digestion, according to an October 2009 report in ‌Food Biophysics‌. This can be another source of stomach pain.

The results of a randomized controlled trial published in the December 2018 ‌European Journal of Nutrition‌ found that, contrary to popular belief, softening almonds by soaking them prior to consumption "does not improve gastrointestinal tolerance."

In 2004, millions of packages of raw almonds were recalled in response to salmonella contamination, prompting the Food and Drug Administration to require that all almonds be pasteurized before sale. These almonds are still labeled as raw.

However, you can still buy unprocessed almonds from farmers' markets and vendors outside the United States, and there is a small chance these nuts could contain cramp-inducing salmonella or other bacteria.

The average American only eats about 16 grams of the recommended 20 to 35 grams of fiber daily, according to the NLM. One ounce of almonds contains 3.6 grams of dietary fiber, according to the USDA. If you eat a lot of almonds and your system isn't accustomed to processing that much fiber, you might develop cramping, bloating and gas for a few days.

Eating over 70 grams of fiber in a day, regardless of the source, can result in cramping, diarrhea and other symptoms of gastrointestinal distress, according to Duke University. If you eat a lot of almonds in one sitting, their high fiber content might put you over your daily limit and cause temporary cramping. In most cases, this fiber-induced pain will subside within a few hours. Contact your doctor if the discomfort persists.

Mention that you have stomach pain after eating almonds, and you just might have someone not-so-helpfully inform you that you are experiencing cyanide poisoning. This is absolutely not the case.

There are two kinds of almonds: sweet and bitter. While it is true that the bitter variety of almonds produces cyanide when digested, that is the very reason that they are not sold as food, as the PLOS blog DNA Science explains. The sweet almonds that you buy in the store produce no cyanide during digestion.

Food intolerances can trigger some of the same digestive symptoms as food allergies, but the two conditions have different causes. According to the National Health Service of the United Kingdom (NHS), food allergies such as almond allergies are the result of the immune system overreacting to the proteins in the nut, while almond intolerance doesn't involve the immune system at all.

Rather, it's the result of the digestive system not being able to fully digest almonds. The undigested portion of the almond enters the colon, where it interacts with various bacteria, leading to gas, diarrhea and abdominal pain.

Almond intolerance isn't life-threatening, but it is uncomfortable. If you have an almond intolerance, you may need to avoid not just eating almonds, but also eating foods that contain almonds, such as almond milk, candy bars, certain cereals and mixed nuts.

According to the Mayo Clinic, experiencing severe stomach pain after eating anything — including almonds — can potentially signal a more serious condition, such as gallstones, ulcers or irritable bowel syndrome. If you develop severe cramping along with a fever, body chills or blood in your stool, call your doctor immediately.