What makes you? Is it your genes, your experiences, or the trillion of microorganisms inside you that shape the person you are today?
Your body is host to a universe inhabited by bacteria, fungi, viruses as diverse and mysterious as the cosmos. Your gut reflects your past and your present — and new research suggests your gut may also predict the future of your health.
Findings from a study published earlier this year in the journal Nature Medicine suggest your diet plays a more prominent role in shaping your gut microbiome than do your genes. In turn, some diets are associated with less diverse microbiomes and an increased risk of obesity, type 2 diabetes, and heart disease.
The discovery — The paper uses data from PREDICT1, the largest international study so far to investigate the relationship between the gut microbiome, diet, and biological changes that may be signs of disease.
The researchers tracked 1,098 individuals’ everyday habits, including their diet, exercise, and sleep. They also analyzed the participants’ stool and blood samples, measured their body fat percentage, and tracked blood sugar levels.
They found fifteen species of gut bacteria associated with a lower risk of diabetes and cardiovascular disease. In contrast, another fifteen bacterial species increased a person’s risk of these diseases. Ultimately, the difference came down to specific food choices.
People who ate a plant-rich diet also had more “good” gut bacteria. For example, high Prevotella copri and Blastocystis species levels were linked to typical blood sugar levels after a meal. These and other ‘good’ bacteria are most associated with a lower risk of obesity, type 2 diabetes, and cardiovascular disease, according to the study.
People who ate more processed foods and foods low in fiber and with high levels of sugar, salt, and artificial additives were also more likely to harbor harmful gut microbes. The researchers uncovered fifteen gut microbes that may increase the risk of weight gain, obesity, heart disease, and diabetes.
Here's the background — The relationship between nutrition and the human microbiome is complex.
On the one hand, prebiotics in yogurts and dietary fibers in raw vegetables promote the growth of good bacteria that protect you from infection and keep you healthy.
But foods high in fat and low in fiber (Western diets) reduce the number of good bacteria in your gut because these diets lack essential nutrients. In addition, when you eat more processed foods, foods high in sugar, red meat, and alcohol, “bad” bacteria flourish in the gut. These bacteria increase inflammation and are similar to those seen in people with inflammatory diseases such as Crohn’s disease, ulcerative colitis, and irritable bowel syndrome.
Why it matters — You can’t do much about your genes, but the study shows that diet may be more important than genetics for some metabolic conditions. Eating different foods can have a measurable difference.
Adding more leafy greens, vegetables, whole grains, and fruits to your diet could help eliminate the “bad” and increase “good” bacteria that regulate your immune system, improve your cognitive function, and prevent age-related diseases.
Rome wasn’t built in a day, and neither were you. Making different choices when you next order in can add up to small but powerful steps toward a healthy future.