Foods That Cause Constipation

The foods that cause constipation play a role in altering our stools, making them harder, slower to move through out systems, and more painful to pass.

The Bristol School Scale, displayed to the right, is what doctors and scientists use to classify human stools. Types one and two indicate constipation, with four being the "ideal stool" that's easiest and quickest to pass. Types five to seven represent worsening types of diarrhea.  (6).

Where do you normally fall on this scale?

Less than half of all people pass ideal type four stools, and the more animal and processed foods you eat the more likely you are have the hard-to-pass stools (7).

In a test of different eating habits and stool results, omnivores averaged a type three, while vegetarians and vegans averaged type 4. The vegans took the lead with stools that were 18 percent softer than the vegetarians (7).

No matter what diet group a study participant was in, as the amount of dietary fiber they ate increased, mean intestinal transit time decreased, stool frequency increased, and stools softness increased (7). Once again, whole plant foods are the key.


Milk is most notorious among the foods that cause constipation for its ability to completely stop people up, regardless of how much fiber they're taking in. The protein in dairy appears to be the main culprit.

In one study looking at 65 severely-constipated children who had bowel movements every 3 to 15 days and didn't respond to laxatives, 44 of the children found complete relief when they simply took all dairy out of their diet (9).

The bowel inflammation, pain, and anal fissures that were stalling their bowel movements faded away. A year later, when those children were reintroduced to dairy, all their symptoms returned (9).

There are also plenty of other reasons to avoid dairy. Learn why you should keep away from the stuff here. 
When I gave up dairy my constipation got a bit better, but it didn't go away entirely. It wasn't until I realized that many of the foods cooked-food vegans eat (particularly processed foods, which have little or no fiber, and all grains and starches) can wreak havoc on your digestive system, that things started to improve.

I suffered from a bad case of colitis, and constipation was just one of the symptoms of that disorder.

What was causing it? Long experimentation with elimination diets and detailed record keeping taught me that as long as grains and starches were in my diet, my colitis was at its worst. When I tried eliminating these foods and switched to a low fat raw vegan diet, though, all my symptoms, especially the bouts of constipation, disappeared completely.

Why was this happening?

Although grains are poorly understood and there appear to be many reasons to avoid them, two elements ravage the intestines of many people.

The gluten found in most grains has been pegged as the cause of coeliac disease, an autoimmune disorder in which the intestines are gradually destroyed, eventually limiting a person's ability to absorb nutrients from their food. Many end up with severe constipation.

As many as 1 out of every 105 people may have coeliac, although most are undiagnosed (11). It's likely that gluten affects the intestines in other ways as well.

Lectins, which are found in high amounts in most grains, have the power to damage our gastrointestinal tracts and then inhibit our bodies' attempts to repair them (10), which makes grains even more questionable.

Also, all grains and starches have a significantly lower water content than whole raw fruits and vegetables, likely leading to digestive issues.

Grains, along with dairy, processed foods, and yeast, have been found to be the primary triggers for a large number of bowel diseases, including Crohn's Disease, which frequently causes constipation (12).

Learn the many reasons to avoid grains here.

Foods That Cause Constipation: The Raw Vegan Advantage

Vegans may trump omnivores and vegetarians, but they've got nothing on those who follow healthy raw diets.

When I started eating only raw fruits, vegetables, and a few nuts and seeds, I began averaging two bowel movements a day, and often have that reach three.

In addition, my stools are perfect fours on the Bristol Stool Scale. This is hardly a burden, because each bathroom break takes only moments. Some people bring novels or newspapers with them to the bathroom when nature calls because they know they'll be there for awhile, but I'm done before I have a chance to read a page. This is a huge difference from the pain, strain, and feeling that I never fully evacuated my bowels I had eating cooked food.

All those following the type of raw diet I recommend seem to have the same experience. The main reason appears to be that low fat raw vegans simply eat tons more whole foods than even vegans, and none of the animal products and processed junk foods that could potentially cause problems. The result is digestive perfection.


If you're looking to get rid of your constipation, I'd suggest a raw diet as the best solution, but you can also try a series of food eliminations to see exactly what's causing your problem. Progress up the list until you find a solution you're satisfied with.

Steps For Overcoming Constipation Eliminate all dairy. Eliminate all meat, dairy, and eggs. Eliminate all animal foods and processed foods. Eliminate all grains, starches, animal foods, and processed foods. Eat only raw fruits and vegetables.