An Apple a Day Keeps the Doctor Away: The Health Benefits of Fiber

by Kathleen Ruff

November 2024

Many people have been told to "eat more fiber" by their doctors but may be curious about the what and the why behind the recommendation. From constipation to its impact on the gut's microbiome – another phrase that might be heard but not explained – fiber has many health benefits.

To understand what fiber does for our bodies, first comes understanding of what fiber is. Fiber is the part of plant foods that can't be digested. Next comes this question: How can a plant product that can't even be digested benefit health? For starters, these undigested plant parts, or fiber, have an action in the gut that relieves constipation. Eating more fiber bulks up the stool. More bulk combined with more water helps push stool through the gut and shortens the time it passes through the colon. In other words, this is a fancy, scientific way of saying that increased fiber makes it easier to get poo from point A to point B, point B being the toilet.

Another health benefit is linked to what fiber does in the "gut microbiome." The gut microbiome is what scientists say to describe the large neighborhood of microscopic organisms that live in the bowels, like good and bad bacteria. Good bacteria use fiber for nourishment to help them grow and accomplish two things: More good bacteria result in less room for bad bacteria to grow and more good bacteria also help the body's immune system to fight off infections.

Additionally, researchers have also discovered fiber's benefits on health conditions like high cholesterol and diabetes. Because high fiber diets are also usually low-fat diets, filling up on fiber-packed foods leaves less room for foods high in cholesterol. For diabetes, a fiber-packed diet does not break down into sugar molecules, so blood sugars are automatically lower. Fiber also decreases the risks of certain cancers like those that start in the colon.

However, fiber benefits can only come if there is enough fiber in the diet. Here's some "how-to" tips for making that happen. First, when available, read food labels for fiber content. Note that nutrition specialists say people should eat between 18 and 38 fiber grams daily. Those grams are packed into foods like grains that are in wheat bread, oatmeal, or even wild rice. Most seeds – like those from pumpkins or sunflowers or any kind of tree nuts – are also good fiber sources. Of course, fruits make the fiber list, like apples that come in at almost 5 fiber grams a piece. In addition to fruits from the grocery store, some North Dakota gardeners might grow raspberries, June berries, or wild plums – all good food fiber sources.

Another way to pack in dietary fiber is through special diets. Nutritionists recommend a diet called the Mediterranean diet that is heavy in vegetables and fruits. Information about this diet can be found online, at the local healthcare clinic, or at the local library.

Although eating foods rich in fiber is the best way to increase dietary fiber in one's diet, this may not be an option for everyone, especially those who dislike all fruits and vegetables. In these cases, fiber supplements are options. Looking at the many supplement choices on a shelf might be confusing, so experts offer these selection tips. First, read the product's label for fiber grams and look for ingredients like psyllium or methyl cellulose. Then consider checking with a provider to make sure taking the supplement does not have impact on prescription medication.

To sum it up, fiber – found in whole grains, seeds, fruits, or supplements – has many health benefits such as reducing constipation, supporting the microbiome, and decreasing the risk of health conditions like diabetes, high cholesterol, and cancer. Because of fiber, it is true what they say: An apple a day keeps the doctor away.

About the Author

Kathleen Ruff is a third-year medical student at the University of North Dakota School of Medicine & Health Sciences. After her clinical experiences in Hettinger, Ruff chose to participate in the Targeted Rural Health Education (TRHE) project, a project focusing on teaching student doctors how to partner with rural newspapers to share health information. The information provided is not for diagnosis or treatment and should not be used in place of previous medical advice provided by a licensed healthcare professional.