How Your Genes Can Help You Find the Best Eating Plan for Your Gut

There are lots of factors to consider when trying to land on the best way of eating for you, including health conditions, budget, and your own taste preferences. But experts say you might also want to look into your family tree for clues as to the best eating plan for you.

Just like what determines our eye color, hair texture, and coffee preference, your genes can also dictate what foods are best for you. That’s because genetics play a role in shaping your microbiome and, in turn, the foods that are truly the healthiest for you. Intrigued? Here, experts explain why your genes affect your food choices and how to figure out what’s truly going to make you feel your healthiest self.

How genetics and diet are connected

In case you need a gut health refresher: The microbiome is the ecosystem of bacteria that live in your gastro-intestinal tract. Their functioning is associated with everything from proper digestive health to mental health. When your microbiome is populated predominantly with good gut bacteria (known as probiotics), you can see and feel the benefits in the form of better moods, increased immunity, and more efficient brain function. But if bad bacteria takes over for an extended period of time—which can happen due to illness, an unhealthy diet, stress, and other factors—you’re potentially at an increased risk of health issues such as inflammation, GI problems, and even some chronic diseases.

Here’s more intel on the importance of gut health, straight from an RD:

As to which bacteria strains make up your microbiome, well, you can partly thank your genes for that. Gerry Bodeker, PhD, an adjunct professor of epidemiology at Columbia University, says that because specific cultures have eaten specific diets for generations, their microbiomes have adapted to those foods. The bacterial strains in the microbiomes are then passed down genetically. “For example, people in Asia tend to eat more seaweed and in Africa people tend to eat more meat. These [eating habits] create, through genetic activation and immune responses, different culturing of the microbiome over time, and that is heritable,” he says.

This may explain why some studies show that certain ethnicities are more prone to some food intolerances than others. For example, lactose intolerance is extremely common in East Asian populations (affecting around 70 percent of people in these communities) compared to people with Northern European ancestry (where lactose intolerance only affects about 5 percent of this community). “What I know anecdotally [from working with clients] is that some people from certain parts of the world have a harder time digesting specific foods and this seems to be connected to variants in the genes, though more scientific research needs to be done,” says registered dietitian Maya Feller, RD.

Our genetic link to our microbiomes is also the reason why there is no one-diet-fits-all—even if it’s one that’s long been heralded as healthy, like the Mediterranean diet. “We hear so much about the Mediterranean diet and it’s promoted as the the go-to diet for cardiovascular health, cancer prevention, diabetes, and obesity prevention, and so on. But how do you explain to more than 67,000 centenarians living in Japan that they made it to 100 years old miraculously?” Dr. Bodeker says, citing the Blue Zones where people regularly live to be over 100 in good health. “They didn’t need the Mediterranean diet and if they switched to the Med diet, they might not have lived to be 100 because that’s not what they’re programmed for.”

How to find the best foods for your gut

So to find the foods that are ideal for your microbiome, we should all just look to our heritage, right? Well, not so fast. Since most of us are a mix of different ethnicities, backgrounds, and cultures, that can be quite the challenge. If your budget allows for it, Dr. Bodeker encourages geeking out on home testing kits like 23andMe (from $99), which can come with an ancestry report, or a microbiome test like Viome ($179), which identifies what foods make your gut thrive and which foods are problematic. Otherwise, Feller recommends paying attention to how different foods make you feel and tracking it in a food journal.

Once you have an idea of what makes your microbiome its best, that doesn’t mean you’re restricted to that diet. Feller’s in full favor of experimenting with different foods from various cultures and seeing how they make you feel. If you experience any physical side effects like bloating or lack of energy, that could be a sign that your microbiome and the new flavors are not compatible. “One way I encourage people to do this is to go by region, just focusing on different places throughout the globe one by one to see what they like,” she says. Have fun getting curious and exploring what’s offered right in your neighborhood. Chances are, you don’t have to go far to expand your palate.

Plus, think of the health benefits you can uncover by broadening your gastronomical horizons. “So many other cultures use spices and herbs and the antioxidant content of some of them is incredible,” Feller says. “So in addition of giving food more flavor, you can get these benefits as well.”

As you incorporate new foods, pay attention to any physical side effects like bloating or lack of energy. That could be a sign that your microbiome and the new flavors are not compatible.

Both Dr. Bodeker and Feller point out that there are other factors besides food that affect the microbiome too, like exercise and stress. For example, if you tend to eat lunch in front of your computer, replying to emails that are giving you anxiety, that can affect your microbiome, too. And certainly if you have any underlying health issues, that of course will as well.

When it comes to healthy eating, genetics are only one piece of the puzzle. But if you’re trying to figure out what to eat in order to feel your best, it may be an important one to consider. Sometimes to look forward, it helps to look back.