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Unlocking the Power of Fiber: How Dietary Fiber Supports Gut Health & Overall Wellness

Dietary fiber is an essential component of a healthy diet. It reduces the risk of metabolic diseases and gastrointestinal conditions; it improves endocrine and immune function, and increased intake is associated with improved quality of life and mental health. Fiber’s beneficial effects can be attributed to the increased production of the short chain fatty acids (SCFAs) acetate, propionate, and butyrate.



Short Chain Fatty Acids (SCFAs)


SCFAs are byproducts of fiber and resistant starch fermentation by beneficial intestinal microbes. They serve as an energy source for the cells lining the colon and help to maintain the integrity and function of the gut barrier to prevent the leakage of harmful substances from the gut into the bloodstream, which can contribute to inflammation and various health issues.   


SCFAs play an essential role in immune regulation by promoting the differentiation and function of regulatory T cells, which help prevent excessive immune responses and inflammation. This immune-modulating effect reduces the risk of inflammatory bowel diseases and other autoimmune conditions. They also improve insulin sensitivity, regulate appetite, energy balance, and have neuroprotective effects that play a role in mood regulation and cognitive health.


Read more about the microbiome and your health here.



The Gut-Brain Axis


The Gut-Brain Axis refers to the bidirectional communication pathway between the gastrointestinal tract and the central nervous system. Intestinal microbes play a pivotal role in this connection, influencing neurotransmitter production, immune regulation, and cognition.


An imbalance in gut microbiota, known as dysbiosis, is linked to various neurological and psychiatric conditions including depression, anxiety, and neurodegenerative diseases like Alzheimer’s Disease and Multiple Sclerosis.


Low fiber diets decrease total SCFA concentration, which alters the gut microbiome, shifting it to a potential pathogenic and pro-inflammatory microbial profile.


The relationship between diet, gut health, and mental well-being highlights the importance of a balanced and fiber-rich diet. By encouraging diverse and healthy gut microbiota through adequate fiber intake, we can support the Gut-Brain Axis and optimize both gut and mental health.

Learn more about the Gut-Brain Axis here.

Fiber and increased production of SCFAs improve…

  • Digestive health

  • Mood and mental health

  • Cardiovascular and metabolic health

  • Liver health and cholesterol levels

  • Inflammation

  • Blood sugar regulation

  • Weight management



Types of Fiber


Soluble fiber…

Soluble fiber dissolves in water and forms a gel-like consistency in the gut to help slow digestion and improve absorption of nutrients. Soluble fiber helps to lower blood sugar and cholesterol levels. Examples include: oats, apples with skin, beans.


Insoluble fiber…

Insoluble fiber does not dissolve in water and remains intact as it moves through the gut. It increases stool bulk and promotes regularity by speeding the passage of food. This type of fiber promotes a healthy gut by feeding beneficial intestinal microbes. Examples include: whole wheat, broccoli, nuts and seeds.


Resistant starches…

Resistant starches resist digestion in the small intestine, passing through to the large intestine where they provide some of the benefits of both soluble and insoluble fiber. Resistant starches can promote feelings of fullness, improve insulin sensitivity, and support digestive health by feeding beneficial intestinal microbes. Examples include: unripe (green) bananas, cooked and cooled potatoes and rice, legumes like lentils, chickpeas, and black beans.


Aim for 25 – 35 grams of fiber per day.


Food Sources


  • Peas

  • Black beans

  • Lima beans

  • Kidney beans

  • Chickpeas

  • Lentils

Whole Grains:

  • Oats

  • Oat bran

  • Barley

  • Psyllium

  • Brown rice

  • Cooked and cooled rice

  • Wheat bran

  • Quinoa

  • Millet


  • Carrots

  • Mushrooms

  • Okra

  • Turnips

  • Parsnip

  • Brussels sprouts

  • Sweet potato

  • Cooked and cooled potatoes

  • Broccoli

  • Cauliflower

  • Leafy greens


  • Avocado

  • Apples

  • Berries

  • Bananas

  • Green bananas

  • Pears

  • Figs

  • Nectarines

  • Apricots

  • Guava

  • Citrus fruits

  • Prunes

Nuts and Seeds:

  • Flaxseeds

  • Almonds

  • Walnuts

  • Chia seeds


Curious about how we can help you optimize your diet? Click the link below to schedule a free virtual consultation!




Parodi B, Kerlero de Rosbo N. The Gut-Brain Axis in Multiple Sclerosis. Is Its Dysfunction a Pathological Trigger or a Consequence of the Disease? Front Immunol. 2021 Sep 21;12:718220. doi: 10.3389/fimmu.2021.718220. PMID: 34621267; PMCID: PMC8490747.


Ramin S, Mysz MA, Meyer K, Capistrant B, Lazovich D, Prizment A. A prospective analysis of dietary fiber intake and mental health quality of life in the Iowa Women's Health Study. Maturitas. 2020 Jan;131:1-7. doi: 10.1016/j.maturitas.2019.10.007. Epub 2019 Oct 13. PMID: 31787141; PMCID: PMC6916712.


Saghafian F, Sharif N, Saneei P, Keshteli AH, Hosseinzadeh-Attar MJ, Afshar H, Esmaillzadeh A, Adibi P. Consumption of Dietary Fiber in Relation to Psychological Disorders in Adults. Front Psychiatry. 2021 Jun 24;12:587468. doi: 10.3389/fpsyt.2021.587468. PMID: 34248690; PMCID: PMC8264187.


Silva YP, Bernardi A, Frozza RL. The Role of Short-Chain Fatty Acids From Gut Microbiota in Gut-Brain Communication. Front Endocrinol (Lausanne). 2020 Jan 31;11:25. doi: 10.3389/fendo.2020.00025. PMID: 32082260; PMCID: PMC7005631.


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