Lifestyle vs Genetics in Influencing Your Gut Health

The types of bacteria you have in your gut create your gut microbiome. This microbiome plays a fundamental role in many functions in your body including the health of your organs. What about lifestyle vs genetics when it comes to influencing your gut health? Have you ever wondered if genetics was more powerful than lifestyle in deciding the fate of your gut microbiome and consequently your health too?

One study provided insight into the answer to this question. Over 1000 people which included hundreds of identical and non-identical twins were studied. Specifically, looking at the effects of lifestyle factors and genetics on your gut microbiome.

It was found that genetics did not influence much about the types of microbes that live in your gut. Twins shared 34% of the types of bacteria in their gut while people who were unrelated shared 30%. What determines your gut microbiome is largely what types of good bacteria or probiotics which you include in your diet as well as the amount of fibre.

The microbes in your gut have such an impact on your metabolism that two people who eat the same meal will have different responses in their bodies to that meal. Postprandial or post-meal effects of a high-fat meal could cause one person to have normal levels of fat circulating in your blood while another person eating that same meal could result in an unhealthy elevation of fat in your blood after a meal. The same effects were seen in a high sugar meal.

Picture of female twins using smartphones sitting on couch
Picture of a salmon salad

An unhealthy gut microbiome was evident with people who ate a diet high in added sugar, salt, low fibre, high in red meat and processed meats. In contrast, the type of diet which was linked to a healthy gut microbiome with lower levels of sugar and fat spikes after a meal was one rich in plant foods, unsaturated oils like extra virgin olive oil, yoghurt, whole grains, and fish.


This healthier diet promoted positive bacteria for the health of your body such as Prevotella copri and Blastocystis spp. Which helped control blood sugar levels. These good bacteria also help to reduce the fat around your organs which promotes heart health.

Take home messageThis study exposes the power you have over your health outcomes by the diet you select – influencing your gut health. There are so many health benefits you can gain by selecting the types of foods that look after the health of your gut.


Asnicar F, Berry SE, Valdes AM, Nguyen LH, Piccinno G, Drew DA, Leeming E, Gibson R, Le Roy C, Khatib HA, Francis L, Mazidi M, Mompeo O, Valles-Colomer M, Tett A, Beghini F, Dubois L, Bazzani D, Thomas AM, Mirzayi C, Khleborodova A, Oh S, Hine R, Bonnett C, Capdevila J, Danzanvilliers S, Giordano F, Geistlinger L, Waldron L, Davies R, Hadjigeorgiou G, Wolf J, Ordovás JM, Gardner C, Franks PW, Chan AT, Huttenhower C, Spector TD, Segata N. Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals. Nat Med. 2021 Jan 11. doi: 10.1038/s41591-020-01183-8.