Consuming mycotoxins produced by some types of molds can cause gastrointestinal (GI) symptoms and other health problems. Constipation is theoretically possible but is likely uncommon.

Mycotoxins are toxic compounds produced by some types of mold. These molds can grow on crops and other types of food, such as:

  • nuts
  • grains
  • spices
  • fruit
  • coffee

Not all molds produce mycotoxins known to harm human health. But regularly consuming contaminated food may lead to health problems like:

  • weakened immune system
  • increased risk of some cancers
  • GI symptoms like nausea and vomiting

Let’s examine the connection between mold exposure and GI symptoms like constipation.

It’s estimated that about a quarter of the world’s crops, like nuts and rice, are contaminated by mold. Consuming food containing mycotoxins produced by some molds may lead to GI symptoms or other health problems.

Some research suggests that some mycotoxins can disrupt the microbiome in your gut. Disruptions to your microbiome can potentially contribute to functional constipation. Functional constipation is when you have infrequent bowel movements without an underlying anatomical cause.

The link between constipation and mycotoxin exposure is largely theoretical, and there’s little to no research connecting the two.

Plus, the Food and Drug Administration (FDA) has a monitoring program to help ensure food you buy isn’t contaminated with mycotoxins. FDA’s monitoring program mainly focuses on the following types of mycotoxins known to be harmful to humans:

NamePossible effectFoods
aflatoxins• increased risk of liver cancer
• birth defects
• kidney and immune system problems
• liver failure or death if large amounts are consumed		• peanuts
• corn
• tree nuts like Brazil nuts and pistachios
• small grains such as rice
• milk of cows eating contaminated crops
deoxynivalenol• vomiting
• nausea
• other symptoms		• bread
• noodles
• beer
• popcorn
fumonisins• brain, heart, liver, and kidney illness in animals• wheat and corn
patulin• kidney damage in animals• fruit
• grains
• cheese
ochratoxin A• kidney damage in animals• grains such as wheat, rye, oats, barley
• coffee
• grapes and wine
T-2 and HT-2 toxins • disruption of ovulation and semen production in animals• grains such as wheat, rye, oats, barley
zearalenone• reproductive issues• corn
• oats
• wheat
• sorghum
• rice

Inhaled mold

Molds release spores that can lead to lung irritation in those with an allergy or sensitivity. Mold and other irritants may activate a type of immune cell called mast cells, which can lead to mast cell activation syndrome.

Research has linked mast cell disorders to an increased risk of irritable bowel syndrome, which involves constipation and other GI symptoms.

Consuming products that contain mycotoxins may also cause other GI symptoms, such as:

Consuming large amounts of some types of mycotoxin can be life threatening. For example, eating food containing large amounts of aflatoxins can lead to liver failure or death.

Ways you can reduce your exposure to mycotoxins

Ways to minimize your mycotoxin exposure include:

  • buying food as fresh as possible and eating it soon after
  • storing food in proper clean and dry areas
  • cleaning bread boxes once a week with vinegar and water
  • removing bread crumbs from bread boxes
  • disposing of food that is moldy
  • throwing away liquids or semi-liquids that are moldy
  • avoiding consuming moldy dairy products
  • storing cereals and flour in a cool, dry place and shaking occasionally
  • buying fruit and vegetables without injuries or bruises
  • storing diet jams in the fridge and throwing away moldy jams
  • throwing away bread if there are moldy spots
  • throwing away moldy meat or sausage (air-dried sausage or ham can still be consumed if you cut away the mold)
  • consuming spices quickly
  • avoiding feeding moldy products to pets, since they can also cause illness in other animals

Long-term exposure to certain mycotoxins can raise your risk of health problems like immunodeficiency and cancer. Other potential problems that can develop include:

  • kidney damage
  • liver damage
  • hormonal problems

Most people are exposed to small amounts of mycotoxins every day since it’s largely unavoidable. Small amounts of mycotoxins are permissible in food products monitored by the FDA if they’re not thought to pose a threat to human health.

It’s a good idea to see a doctor about constipation if you’re regularly constipated or if you’re taking medications that can cause constipation, such as opioids. It’s also important to see a doctor if you notice blood in your stool.

Mycotoxins produced by some molds may cause GI and other health problems. The FDA regularly monitors for contaminated food to make sure you don’t consume foods that may be harmful to your health.

It’s theoretically possible that mold exposure may play a role in the development of constipation for some people.

However, constipation has many other causes that are more likely, such as medication side effects, dehydration, or lack of fiber in your diet.