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
Legumes:
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
Vegetables:
Carrots
Mushrooms
Okra
Turnips
Parsnip
Brussels sprouts
Sweet potato
Cooked and cooled potatoes
Broccoli
Cauliflower
Leafy greens
Fruits:
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!
References:
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.
Disclaimer: The entire contents of this website are based upon the opinions of physicians at Pacific Clinic of Natural Medicine, unless otherwise noted. Individual articles are based upon the opinions of the respective author, who retains copyright as marked. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of our physicians and their community. PCNM encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional. If you are pregnant, nursing, taking medication, or have a medical condition, consult your health care professional before using products based on this content.
If you want to use an article on your site please direct to and cite the original article page. This content may be copied in full, with copyright, contact, creation and information intact, without specific permission, when used only in a not-for-profit format. If any other use is desired, permission in writing from PCNM and the original author is required.