Fiber

Fiber is a kind of carbohydrate that cannot be digested directly by humans, and as such is usually said to have no calories.

Despite not being digestable by humans and not contributing any calories to human nutrition, it is incredibally important for human health, because it serves several purposes:

• It helps regulate bowel transit time (and therefore the balance between stool that is "too soft" (diarrhea), "too hard" (constipation), and "just right").
• It acts as a "pre-biotic" that helps feed beneficial bacteria in the gut, and by extension, increases "good microbiota" and reduces "bad microbiota." in the gut.
• Beneficial bacteria can digest fiber, and when doing so produce a short-chain fatty acid called "butyric acid" which is the primary food for the cells that line our colons (colonocytes). When our colonocytes are well-fed and happy, we have less gut inflammation, less "leaky gut" (intestinal hyperpermeability), fewer food allergies or sensitivities, and fewer auto-immune disease problems.

Digestible fiber is bascically the same thing as Complex Carboyhydrates.

Non-digestible fiber can be divided into two categories, based on their water solubility:

• Soluble Fiber [benefits persons with too-soft stools]
• Insoluble Fiber [benefits persons with too-hard stools]

Non-digestible fiber can also be divided into two different categories, based on their chemical structure:

• Fermentable Fiber
• Non-Fermentable Fiber

Good sources of soluble fiber include [Healthline]:

• Legumes: peas, beans
• Fruits: apples, citrus [containing pectin]
• Grains: oats, barley
• Roots: carrots

Good sources of insoluble fiber include [Healthline]:

• Bran: wheat bran
• Nuts
• Non-starchy vegetables: cauliflower, green beans, [green leafies]

The most important of these kinds of fiber are the fermentable fibers; these are the ones fhat feed our colonocytes. Unfortunately the foods rich in these is poorly documented in the scientific literature. Good food sources of fermentable fiber include [Sears2019, pg 265]:

• Legumes: beans, lentils
• Some fruits: berries, apples, pears
• Fungi: Mushrooms

Dr. Weyrich notes that adequate water must be consumed along with fiber.

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  Carbohydrates

•       [Sears2019]   Bary Sears. The Resolution Zone. (2019). Amazon
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  [healthline]