Many people assume that taking probiotics will increase the number of healthy bacteria that are in their gut, but as I’ve discussed before, this just isn’t true.
In fact, the research indicates that probiotics alone do not significantly change the quantity of good bacteria in the gut.
So, you know that you need a rich and diverse gut microbiota, but if you can’t get it through taking probiotics, how do you get there?
Simple. You feed the ones you already have!
Failing Our Microbiota
It’s no secret that the Standard American Diet (SAD) and the diets of most other industrialized nations are pretty terrible in many regards, and dietary fiber intake is no exception. Our gut microbiota feeds on many of these dietary fibers and the intake of such fibers is positively correlated with overall gut health and function.
The Hadza from north-central Tanzania are one of the few hunter-gatherer societies still intact and they have very little influence from the outside world. Jeff Leach from the American Gut Project reports that the Hadza people consume an average of about 100 grams of fiber per day. And it is speculated that traditional hunter-gatherer societies got as much as 135 grams of fiber per day.
Compare this number to the average American that gets about 10 to 15 grams per day. They eat almost 10 times the fiber that the average American does.
You might say, “Well, I follow a Paleo diet and eat lots of vegetables, I must get a lot more than that!”
Not much more. The average person following a Paleo diet gets about 25 grams of fiber per day. Better, but still falling way short of our ancestors.
The problem is that we don’t eat a lot of the high-fiber wild plants that our ancestors ate. They consumed over 100 different species of plants. Now, the typical person in the US and other industrialized countries consumes only 15 to 20 species throughout their entire life.
Our diets and the type of food we eat play a big role in this deficiency, but our food has evolved over the years to be more palatable and calorie dense. This has led to a decrease in fiber and nutrient content. I wrote more extensively about this in my article, “Nutrients of Yesteryear.”
Not All Fiber Is Created Equal
There are several different classifications of fiber and there is not a true consensus on which classification is the “right” one. Some classification systems are based on the digestibility of the fiber and others are based on solubility.
These are both fine for scientific purposes, but for practical purposes, we’ll focus on how fermentable the fiber is. This will give us insight into what our bacteria can use as fuel.
These fermentable fibers have many different health benefits, from increasing the number and health of beneficial bacteria to increasing the production of short chain fatty acids and improving gut barrier function.
Fermentable fibers seem to favor the proliferation of beneficial bacteria. Lactobacillus and Bifidobacterium species seem to especially thrive on fermentable fibers. A thriving population of these species have been linked to many health benefits including healthy metabolic function and decreased autoimmunity.
Another benefit of fermentable fiber is that it increases the production of short-chain fatty acids. These fatty acids provide a wide array of benefits, including:
- Increasing the acidity of the colon, making it less hospitable for pathogens
- Promoting cell differentiation and proliferation
- Regulating sodium and water absorption
- Enhancing absorption of minerals that are essential to bodily functions
Lastly, fermentable fibers have been noted to improve the gut barrier function, keeping out pathogens and other potentially harmful substances.
How You Can Feed Your Friends Starting Today
By now, I’m sure you see the benefit of ensuring adequate fermentable fiber in your diet, but the question becomes, how do you get it? How do you feed your friends?
Chris Kresser has mentioned many times that with each bite of food, you should ask yourself two questions.
- “How does this nourish and feed me?”
- “How does this nourish and feed by microbiota?”
This may sound a little kooky, but maintaining gut health has been proven to decrease the likelihood of psychiatric and mood disorders, autoimmune disorders, and a number of other chronic diseases.
Here are some good options for getting more fermentable fiber in your diet:
|Fiber Type||Dietary Sources|
|Inulin||Garlic, onions, leeks, chicory root, Jerusalem artichoke, dandelion root, burdock root, yacon|
|Beta-Glucans||Mushrooms, dates, oat fiber|
|Pectins||Fruit (peaches, apples, oranges, grapefruit and apricots), vegetables (carrots, tomatoes, potatoes) and peas|
|Resistant Starch||Cooked and cooled potatoes and rice, lentils, green plantains|
When you start introducing these food sources of fermentable fiber, start slow and build over time. If you have any underlying gut pathologies, you may find that introducing large amounts of fermentable fiber is not such a good idea. It can cause cramping, bloating, and gas.
Supplementation can be helpful, but it’s always best to start with whole-food sources of fiber. We’ll explore supplement options in future articles.
To help you get started on the right foot, I’ve created a quick reference that you can use. In this one-page document you will find information on the types and quantities of fiber you should be consuming, dietary sources of these types of fiber, and supplements that can be used to serve as prebiotics.
To get your free copy of the Feed Your Friends: Dietary Fiber and Prebiotic Quick Reference, just click here, enter your email address and I’ll send it to you in PDF format so you can reference it whenever needed.