Folate is a type of vitamin B needed for humans to perform critical functions such as the production of red blood cells. Although folate can be obtained from the diet, microorganisms in the colon produce a stable supply of the most easily absorbed form of folate and are important influencers of a person’s folate status. Folates occur naturally in many foods, especially dark green leafy vegetables, liver, and lentils.

The vitamin folate (aka B-9) is widely known for its role in fertility, pregnancy, and preventing serious birth defects. But did you know it also supports critical functions like the production and maintenance of red blood cells and DNA? Women are routinely told to fortify their bodies with folate, typically through nutrition-rich foods like leafy greens, avocados, and citrus fruits, or in the synthetic form—folic acid, via supplements.

When you take a folic acid supplement, it goes through a metabolic pathway in your liver to convert it into the bioavailable form of folate called methylfolate (5-MTHF). This is the form your body can use. 20-40% of women actually have a genetic mutation called MTHFR that prevents them from processing synthetic folic acid into usable folate. And for them, folic acid just sits in their liver, and over time, the buildup can actually be toxic.

The good news is, microbes in your gut can synthesize a number of essential vitamins—folate being one of them. So instead of relying on external supplementation, you can actually help your internal pharmacy create what it needs to thrive.