Intermittent Fasting Causes Constipation, Bowel Movement Problems — Here’s Why

Intermittent fasting is all the rage these days in the fitness world despite the pandemic, and there’s a good reason for it. The diet is known to effectively shed pounds. However, it is not free from side effects that could be very uncomfortable.

Apparently, intermittent fasting causes constipation. Some people who follow the diet also claim that they experienced diarrhea. Based on testimonies and anecdotal evidence, the eating plan appears to lead to bowel movement problems, especially during the initial phase of its practice.

Experts have weighed in on the issue, and they said that the poop problems are part of the changes that the body experiences as it adjusts to intermittent fasting. Because the diet is all about restricting the intake of food for certain periods, the body will have to adjust to the new schedule of food consumption.

“Changes in diet very easily can cause changes in bowel movements. With regard to intermittent fasting, people may suffer from constipation as a result of dehydration and poor dietary fiber intake,” Cynthia Quainoo, M.D., told Women’s Health.

Quainoo, who is a gastroenterologist at Gastroenterology Associates of Brooklyn, explained further that intermittent fasting followers could suffer dehydration when the fasting period takes a long time. Since food is also a good source of water content, the body’s need for fluids could be compromised.

As for people who claim they have experienced diarrhea while on intermittent fasting, Quainoo said that the diet does not at all cause this condition and there could be other reasons for this such as colon infection, lactose intolerance, thyroid disorder, or certain medications.

Aside from constipation and bowel movement issues, MayoClinic said that intermittent fasting could also have other unpleasant side effects, like fatigue, nausea, headaches and insomnia. Hunger could also be a side effect since meals are not being consumed in regular time intervals as before.

According to Diet Doctor, people who do not follow the protocols of intermittent fasting religiously are those at risk of experiencing its side effects. Furthermore, the bodies of those who are new to this type of diet would need more time to process the changes in food intake.

The good news is once the body has fully adapted to the changes, the side effects would disappear. Most side effects go away completely within a few weeks as long as the routine is being followed consistently.