Fermented foods have been around since ancient times and are found in cultures around the world, from Roman sauerkraut to India lassi to Korean kimchi. Just as fermented yeasts are used to make wine, sugars and starches are fermented with lactic acid to produce bacteria such as lactobacillus and bifidobacteria. This process is called lacto-fermentation.
The Weston A. Price Foundation holds fermented foods in high regard. They are quick to point out that in addition to preserving food, the fermentation process creates prebiotic foods that help maintain good levels of beneficial bacteria in the gut. These beneficial bacteria then help create beneficial enzymes, produce B vitamins, increase the bioavailability of certain minerals, and produce the short-chain fatty acids that are necessary for gut health.
Some of the most common fermented foods are listed below. As a note, even though a few of these contain soy (which can be a problematic food for many people), soy foods have been found to be safe in their fermented form.
You might want to consider making your own fermented foods rather than relying on store-bought products. Since fermentation is a natural process that takes a long time (or at least, “long” in terms of commercial food manufacturing time) and may have varied results, commercial food producers have tried to speed up and homogenize their fermented foods. You could argue, for example, that pasteurization defeats the whole purpose of fermented foods, because heat destroys beneficial enzymes and bacteria. Be sure to watch out for pasteurized yogurt with added cultures—better to eat cultured dairy products that were cultured from the beginning. Likewise, olives and pickles that have been pasteurized and stored in salt and vinegar won’t offer as many benefits as those that have been lacto-fermented.
When it comes to traditional fermented foods, Nourishing Traditions: The Cookbook that Challenges Politically Correct Nutrition and the Diet by Sally Fallon is a great resource.
One more note: with truly fermented foods, it may be best to start by eating very small servings to avoid die-off and detoxification reactions. You may also want to include a variety of these types of foods in your diet to get the benefits of consuming a mix of microorganisms.
Don’t forget your prebiotics!
Why is prebiotics important? Turns out that there are over 50 different types of bacteria in our colon, and these bacteria ferment soluble fibers such as inulin, fructooligosaccharides (FOS), and resistant starch (RS) to form acids such as butyric acid, propionate acid, and acetate. Because our body is so smart, it designed our gut cells to use these acids to maintain a healthy gut lining.
With FOS as fuel, a well-fed army of friendly bacteria such as bifidobacterium and lactobacilli can compete with pathogenic bacteria, thereby effectively slowing their growth and keeping our gut healthy.
Inulin comes from flowering plants such as chicory, onions, asparagus, Jerusalem artichokes (also called sun chokes), garlic, etc. The short chains of fructose or oligosaccharides created by the breakdown of inulin are commonly referred to as FOS.
Maybe now you can appreciate how important foods like garlic and onions really are for our gut health! If you find you have an issue with these two super foods, you might need to reduce the consumption of sulfur containing foods.
Now onto Resistant Starch. Restarch (RS) is kind of a “mutt” formed from starch and fiber. Instead of being turned into glucose, RS travels to the colon intact. There, it can feed our gut bacteria.
There are actually 4 types:
- RS found within plant cell walls: partially milled beans, grains, and seeds
- RS that is indigestible raw due to its high amylose content: potatoes, unripe bananas, and plantains (these starches become accessible with cooking and then act like a normal starch)
- RS that has been cooked and then cooled: potatoes, grains, and beans
- RS that is in man-made ingredients: “hi-maize resistant starch,” potato flakes, bean flakes
RS feeds our gut bacteria so that they in turn create the short-chain fatty acids that keep our gut cells healthy. Happy cells absorb minerals and create vitamins. Another huge bonus? Happy gut cells don’t turn into leaky gut.
Resistant starch improves blood sugar and insulin response, lowers cholesterol and triglycerides, increases the ability to feel full, and reduces fat storage. Sounds great to me! In addition, RS may help with mineral absorption. A study by the Children’s Nutrition Research Center found that for baby piglets, a meal with 16.4% of RS resulted in greater absorption of calcium and iron. The researchers only tested the absorption rate of a few minerals, but I believe that this technique would also help with other minerals and that RS would help humans with mineral absorption as well.
Another bonus. Studies by the American Society for Clinical Nutrition found that 50 grams of RS resulted in significant reduction in post-meal sugar and insulin levels while creating a feeling of satiety.
You might want to start with a much lower amount and working up to 50 grams so you don’t get a die-off reaction (or ill effects from toxins being released by dying bacteria). It might also be possible that you can use RS as an indication of the health of your GI system. If there is an issue with your gut, you may respond negatively to RS and experience gas, bloating, etc. and makes sense since RS helps fight “bad” bacteria by feeding the good ones which can help alleviate many health issues.