Nuts and Stomach Discomfort

Most people don’t have problems with nuts and stomach discomfort; even though in reality they are difficult to digest because of the relatively high fiber and fat content.  They are digested slowly (a good thing for hunger) increasing the risk of digestive problems like bloating and gas.  Nuts also contain tannins which can interfere with digestion in some people.

[pullquote align=”right” textalign=”right” width=”30%”]Soaking nuts and seeds overnight in salty water is an easy way to make them more digestible and remove most of the phytic acid and other antinutrients.  After the nuts have soaked for a number of hours, rinse them thoroughly and dry them under the sun, in a dehydrator or oven set at the lowest temperature.[/pullquote]

See your doctor if your stomach hurts every time you eat nuts to rule out any serious health issues.  The timing of your pain, how long it lasts, and how much it hurts are all clues to the cause and severity of your condition.

What to Look For

Pay attention to two things in particular after you eat the nuts: 1) How soon after you eat them does your stomach start to hurt and 2) what else you eat with them.  If your stomach hurts right away you could have a nut allergy.  If it starts several hours later, when the food has had time to arrive in your lower intestine, then gas is more likely the culprit.  If the pain kicks in suddenly and all it once, it could be a gall bladder issue (you would notice this if when eat other fatty foods as well).

Gas pains are characterized by sharp pains and the pain can “move.”   This can be caused by an imbalance in your flora.  Nut allergies are usually accompanied by other allergy type symptoms – tingling in the mouth, itchy throat, hives or even swelling.  The gall bladder holds bile from your liver, which helps your body digest fats.  Sometimes, the ducts that let bile flow out of the gall bladder and into the small intestine get blocked by gall stones.  Pain from a gall bladder attack is often just under the ribs on the right side of the body, and it starts 15 to 90 minutes after eating.  Gall bladder issues typically aren’t limited to only eating nuts, but any high fat foods or large meals.


If you have severe pain when you eat nuts, see your doctor.

If you experience moderate discomfort try eating fewer nuts in one sitting to help your system get accustomed to them. You can also try over-the-counter digestive aids to help break down nut carbohydrates.  Also try soaking, freezing or roasting your nuts before you eat them.  Worse case, just avoid them; but try not to eliminate them entirely, because nuts are an excellent source of of vegetable protein and heart-healthy monounsaturated fats.

 Paleo/Primal Note

  • Eat nuts in moderation for a few main reasons:

– Most nuts contain lectins that can irritate the gut lining;

– Most nuts also contain phytic acid that bind to minerals (zinc and magnesium) and blocks their absorption;

– Most nuts are very high in total polyunsaturated fat and in omega-6 fat, two things that should be kept to a minimum;

  • The “best” nuts are:

– Macadamia nuts, high in monounsaturated fat, healthy even in high amounts;

– Chestnuts, starchy and very low in polyunsaturated fat, beneficial as a source of healthy carbohydrates;

– Brazil nuts, high in omega-6 and total PUFA, but also extremely high in selenium selenium;

And remember,  you can improve the digestive profile of nuts and seeds by soaking them in salty water overnight.

Article Sources:

  1. Today I ate handful of macadamia nuts and went for a short bike ride. Once I got home I felt a sudden sensation in my stomach like I wanted to vomit. If i bend over at all the pain rises, if I sit and relax and don’t move too much the pain falls and goes away, but returns if I move about. It’s not the gall bladder pain, cause it’s the entire stomach region that’s hurting and I have no other pain or sensations anywhere. I did drink orange juice after the bike ride. Any ideas as to why I got such pain?

    • Foods with a lot of fat or fiber can be very difficult and slow to digest and remain in the stomach a long time and should be avoided before exercise. Macadamia nuts would fall into the “high fat” category. They also will pull blood into the stomach to aid in digestion, which can cause cramping and discomfort. If you eat at all before exercise, it should be items that relatively high in carbs are easy to digest. But every athlete is different so eating before exercise is something only the athlete can determine based upon experience (Source: Quinn, Elizabeth. What to Eat Before Exercise). BUT, as always see your doctor to rule out other others is you experience pain when you eat nuts.