Fiber, Fat Loss, and Performance: How Fiber May Improve Your Workout

Fiber, Fat Loss, and Performance: How Fiber May Improve Your Workout

Dietary fiber intake has been linked to weight loss and energy production. Not getting enough of this essential nutrient is common and could be detrimental to health. Fiber supplements were created to fill a gap in the diet. Learn if these products can increase fiber, fat loss, and improve your workout.

What are Fiber Supplements?

Dietary fiber is a nutrient that comes from plants and is indigestible for humans. It comes in two forms: soluble and insoluble.

Soluble fiber dissolves in water and forms a gel. It passes through the digestive tract and is then fermented by bacteria in the colon.

Insoluble fiber provides a bulking effect and helps food pass through the digestive tract [R].

Fiber supplements were created to help improve fiber intake in the diet. They are derived from both natural and synthetic fibers. They include the following: psyllium, inulin, methylcellulose, wheat dextrin, and corn [R].

How Do Fiber Supplements Work?

Soluble fiber slows digestion and increases the absorption of nutrients along the small intestine. When nutrients are absorbed in the small intestine it will increase satiety and slow down how fast food leaves the stomach. This will reduce hunger and overall food intake [R].

The bulking effect of insoluble fiber improves constipation, bowel movements, and regularity [R].

Benefits of Fiber Supplements

Research shows daily fiber intake is needed for a healthy diet. It is associated with improved gut health, decreased blood pressure, and regulated blood sugar. It also plays a role in cancer prevention and heart health. Fiber intake may lower the risk of heart disease and colon cancer [R, R, R, [R].

Fiber, Fat, and Performance

Fiber’s metabolic effects can help you lose weight.

Middle-aged women lost an average of 4.4 pounds after consuming 8 grams of dietary fiber a day for 20 months [R].

Fiber may amp up your physical agility. Older adults with fiber intakes over 19 grams a day demonstrated faster gait speed, longer 6-minute walk distance, faster timed “up and go” (TUG), and higher handgrip strength [R].

Fiber for Muscle Growth

Fiber’s positive effects on insulin and blood sugar control building and maintaining muscle [R].

Muscles need a strong immune system to thrive. Fiber helps to colonize healthy bacteria and improve immune function [R, R, R].

The compound sex hormone-binding globulin (SBHG) improves protein synthesis leading to muscle growth. Diets low in fiber were associated with lower levels of SBHG [R, R, R].

Fiber may also spare body testosterone. Urinary losses of testosterone were 13% higher in men with a low-fiber, high-fat diet than with a low-fat, high-fiber diet [R, R].

Food Sources of Fiber

Fiber can be found in fruits, vegetables, nuts, seeds, and legumes. Soluble fiber consists of oat bran, barley, nuts, seeds, beans, lentils, peas, citrus fruits, apples, strawberries, peas, and potatoes [R]. Wheat bran, whole grains, corn, eggplant, green beans, broccoli, spinach, kale, legumes, kiwi, strawberries, raspberries, pineapple, blueberries, and raisins are types of insoluble fiber [R].

Recommendations of fiber intake are between 25 to 38 grams a day. Most people get only half of that [R].

Fiber from food sources is the best way to get fiber in the diet. However, if you are unable to meet your goals a supplement may be helpful to increase fiber intake.

What to Look for in a Fiber Supplement

Fiber supplements can be taken as a powder, tablet, or capsule. Pick a supplement with quality ingredients, no fillers, and is third-party tested for purity.

Fiber supplements are only effective if they have the gel-forming ability that occurs with the consumption of fiber-rich foods. Psyllium fiber is an example of this type of supplement [R, R].

Fiber Dosage Recommendations

There are no formal dosage recommendations. It is best to start with a very low dose and gradually increase it over a few days.

Follow the directions on the label and be sure to drink at least one to two liters of water a day.

Side Effects & Contraindications of Fiber Supplements

Too much fiber may slow athletic performance and cause constipation [R, R].

Fiber supplements do not provide the additional nutrients found in whole foods. If your diet is poor and your main source of fiber is a supplement your nutrition may be at risk [R].

Contraindications and side effects also come with taking this supplement.

Side Effects of Fiber Supplements

Having too much fiber too quickly causes gas, diarrhea, stomach cramps, bloating, and constipation [R].

Taking more than 50 grams per day increases the risk of intestinal blockage and dehydration. It also reduces mineral absorption and can lead to deficiencies [R].

Contraindications of Fiber Supplements

Too much fiber can interfere with antidepressants, statins, penicillin, diabetes, and epilepsy medications.

Final Thoughts on Fiber Supplements

Fiber is an essential nutrient that needs to be consumed daily. Its metabolic effects have been tied to improved health and performance. Unfortunately, many people are lacking in their fiber intake which can result in poor health. Consuming dietary fiber from foods is the best way to improve fiber intake. If you are lacking in the fiber department a psyllium fiber supplement may be just what you need to improve your health and physical prowess. It is best to seek medical advice from a trained health professional before starting a fiber supplement especially if you are on medication or have any health conditions.


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