On October 20, the US celebrates National Diversity Day. It turns out that diversity isn’t just important for society. It is important to your health – especially your gut microbiome. This is the collection of bacteria that reside in our guts. There are trillions of these bacteria, mostly “good guys” as opposed to pathogens. Collectively they weigh between 2 and 3 pounds.

We have learned a great deal about gut bacteria in the last five years, when over 50,000 scientific articles were written. While there is no perfect gut microbiome, research shows that a diversity of bacteria can improve health and mitigate illness such as cardiovascular disease, diabetes, and even Alzheimer’s (1, 2, 3).

Why Diversity Matters

Geneticist Giles Yeo from Cambridge compares the gut microbiome to a garden. If its ecosystem includes a wide variety of plants and flowers, it will thrive. If it only has a few types of plants, weeds will take over. The same is true for your gut. Bacterial diversity keeps us healthier and reduces the risk of pathogens which are linked to disease.

What You Eat Makes a Difference

One of the best ways to help your gut bacteria thrive is to eat a variety of fruits and vegetables. These contain fiber which serves as a prebiotic. Think of this as fertilizer for the garden. While humans can’t digest fiber, our gut bacteria can. When they do, they transmit anti-inflammatory signals that are picked up by our immune cells and communicated throughout our entire body. This reduces low-level chronic inflammation which is associated with a host of chronic diseases.

What About Probiotics?

If a prebiotic is the fertilizer, a probiotic is a new variety of grass seed. Ingesting foods like yogurt, sauerkraut, or kimchi which have live bacteria introduces other types of good bacteria into your system. Eat these foods if you enjoy them, but don’t take supplements unless your doctor has prescribed them. Research shows no link between commercially available probiotics and health, except in cases of pediatric diarrhea.

The Top Takeaway

Eat more fiber to improve your gut health. Aim for 25-30 grams a day. (Most Americans eat 10 grams.) Consuming a variety of fruits and vegetables has a two-fold benefit: it increases fiber and adds powerful antioxidants which reduce the effects of cellular aging.