Fiber plays a huge role in maintaining and improving upon regular functions of the body. In fact, studies have found that older adults who took a fiber supplement to help them reach their daily dietary fiber goals saw improved performance on brain function assessments over time.
“With the research we have, we can better understand why it is incredibly important to prioritize diet as it relates to your overall health and longevity,” says Ryan Barish, M.D., a functional medicine specialist at Henry Ford Health. “Since most Americans aren’t even consuming 50% of the recommended daily fiber, upping your intake can benefit the body’s gut brain connection and ward of cognitive decline.”
Fiber Basics
There are two types of fiber – soluble and insoluble (or the difference if they dissolve in water or not) – that are related to different functions in the body. Eating a variety of both helps keep your system regulated.
Soluble fiber helps feed the bacteria in your gut and slows glucose and fat in your bloodstream to keep your blood pressure balanced and help you feel full. Sources of soluble fiber include black beans, Brussel sprouts and sweet potatoes.
Insoluble fiber helps to move your gastrointestinal tract along by preventing diarrhea or constipation. Examples include lentils and peas.
Current dietary guidelines suggest that adults consume 14 grams of fiber for every 1,000 calories. This comes out to about 28-34 grams for adults depending on age and sex. Dr. Barish recommends tracking your meals to better understand how much fiber you are really eating.
How Your Fiber Intake Relates To Brain Health
The correlation between your fiber intake and brain health is a key part of your body’s gut brain connection. If your gut isn’t getting enough fiber, processes in the body and brain can become affected. In fact, research comparing a low fiber diet versus a high fiber diet and found that high fiber diets resulted in a lower risk of mortality from cardiovascular disease, stroke and cancer.
Here are a few ways fiber impacts the body:
- Fiber helps produce butyrate, a short-chain fatty acid proven to enhance your learning capabilities and memory. The bacteria in your gut consumes fiber (in the form of prebiotics) and metabolizes it like a carbohydrate to create butyrate. Some studies show that butyrate may interfere with the creation of plaque buildups related to dementia and Alzheimer’s disease. Additionally, there are a few limited studies that show that this fatty acid could also help reduce your risk for Parkinson’s disease.
- Consuming fiber improves your glucose absorption and blood pressure levels – lowering risk for diabetes and dementia. “We often call dementia the third type of diabetes since the risk factors for the conditions are so closely related,” says Dr. Barish. “Improving upon your blood sugar and blood pressure levels as well as other risk factors for diabetes can significantly lower your risk for dementia.”
- Fiber helps with serotonin production. Serotonin is a chemical messenger in the body that affects your mood, memory and other bodily functions including sleep, hunger and cardiovascular function. As much as 95% of your body’s serotonin production happens in the gut. Eating a diet high in fiber is a good way to naturally boost your serotonin levels.
- Fiber can increase brain-derived neurotrophic factor (BDNF). BDNF is a protein found in the brain and spinal cord that helps protect neurons and impacts your memory. Using fiber to balance your gut bacteria can play a big role in the levels of this protein in your body.
- High fiber diets can prevent gut imbalances caused by your brain health. If you have anxiety or elevated cortisol levels, it can have a negative impact on your gut bacteria – potentially causing an overgrowth or imbalance – causing inflammation and dietary changes. Fiber helps protect the lining of your gut to help your body regulate.
Henry Ford Center For Integrative Medicine
How To Increase Your Fiber Intake
If you are looking to up your fiber intake, Dr. Barish recommends that you always try to get fiber from your food first.
“The idea is to try to get all the fiber you need from a mostly plant-based diet,” says Dr. Barish. “When you meet with a functional medicine doctor, we check your gut bacteria and how that coordinates with your symptoms. If needed, supplements can have a therapeutic affect and closes the gaps in your nutrition if necessary.”
Here are a few ideas of foods that are high in fiber:
- Fruits such as apples, bananas and pears
- Vegetables like leafy greens and cruciferous vegetables
- Whole grains such as oatmeal and whole wheat pasta
- Legumes like beans, lentils and chickpeas
- Nuts and seeds such as chia seeds, almonds and pepitas
Reviewed by Dr. Ryan Barish, a functional lifestyle medicine physician who sees patients at Henry Ford Medical Center - Bloomfield Township.
