- Researchers say a plant-based diet such as the Mediterranean diet can improve the gut microbiome in a number of ways.
- One study concluded these diets can increase the type of gut bacteria associated with healthy aging in older adults.
- Another study concluded plant-based diets can reduce the kind of gut bacteria associated with heart disease.
- Experts say plant-based diets can also reduce inflammation in the body and improve a person’s overall health.
There may be two more reasons for you to eat a plant-based diet.
Researchers in separate studies say diets such as the Mediterranean diet can increase the type of gut microbiome associated with healthy aging.
They add these diets can also decrease the kind of gut microbiome associated with heart disease.
Specifically, the two studies published this week found that a diet high in plants and low in animal products can influence gut bacteria that can cause the onset of frailty in older people as well as increase the risk of coronary heart disease.
Dr. Emeran Mayer, author of “The Mind-Gut Connection” and co-director of CURE: Digestive Diseases Research Center at the University of California Los Angeles, says diet can make a big difference when it comes to the onset of frailty and cardiac health.
“The diet is one of the most important parts of treating or preventing these problems. I’m a big supporter of a largely plant-based diet… There is, in my mind, no question whatsoever that this is the healthiest diet,” Mayer told Healthline.
One study published in the journal Gut found that in older adults eating a Mediterranean diet for a year helped curb the onset of frailty and cognitive decline.
Researchers examined the gut microbiome of 612 people ages 65 to 79 before and after a 12-month period of eating either their own diet or a Mediterranean diet.
Those on the Mediterranean diet saw beneficial changes to their gut microbiome, including a proliferation of good bacteria that pushed out microbes associated with the onset of frailty.
“The Mediterranean diet has an abundant amount of research backing it up as a healthy diet. The diet is high in fruits, vegetables, whole grains, beans and legumes, fatty fish, healthy fats like nuts, seeds and olive oil, and small amounts of poultry. It also allows for a small amount of red wine,” Kristin Kirkpatrick, MS, registered dietitian and manager of wellness nutrition services at the Cleveland Clinic Wellness Institute in Ohio, told Healthline.
The researchers say the changes were likely due to an increase in dietary fiber as well as vitamins and minerals such as vitamin C, B-6, iron, and magnesium, among others.
A poor or restrictive diet is thought to be more common in older people, in particular those in care settings.
“There is a common misconception that seniors’ diets need to be soft and as such, fruits and vegetables are minimized,” Lauri Wright, PhD, an assistant professor in public health at the University of North Florida, told Healthline.
She says there are numerous benefits to eating a largely plant-based diet such as the Mediterranean diet.
“​Plant-based diets are a healthier option to build gut health and therefore cognitive health, heart health, and diabetes prevention and management. Focus on more ‘meatless entrees’ such as bean burgers or beans and rice. Also, make your plate more rich in fruits and vegetables overall,” she said.
Another study published in the Journal of the American College of Cardiology found that eating fewer animal products and following a largely plant-based diet reduced the amount of gut bacteria associated with an increased risk of coronary heart disease.
The gut’s microbiome plays an important role in digestion and metabolism. A metabolite (a substance created during the digestion process) known as TMAO is created when bacteria in the gut digests nutrients found in animal products such as red meat.
TMAO has been linked to an increased risk for heart attack and coronary heart disease.
Researchers said following a vegetarian or vegan diet lowers the amount of TMAO in the body.
In the study of 760 women ages 30 to 55, those who developed coronary heart disease had higher levels of TMAO in their body.
Mayer says the findings reinforce the important link between the microbiome and the heart.
“There’s a close connection by multiple pathways between microbes and cardiac health,” he said.
Dana Hunnes, PhD, a senior dietitian at the University of California Los Angeles Medical Center, says she advises her patients with cardiac problems to eat less meat.
“We know that inflammation and an unhealthy gut microbiome increase the risk for multiple chronic diseases, including heart disease. This does not surprise me at all as I’ve been telling my cardiac patients for years to follow a more plant-based, whole foods diet,” Dr. Hunnes told Healthline.
“I have yet to find any real positive impacts on the body from eating animal products, especially on the heart,” she added. “So many studies point over and over again to the fact that a plant-based diet is healthier for our arteries, our heart health, cholesterol levels, inflammation, weight, and other aspects of health that may increase or lower the risk of heart disease.”
Mayer says with so much conflicting diet advice available to the average person, it can be difficult to know what foods are best to eat.
“It’s very difficult for the consumer. It’s got to be the most confusing area in medicine or in prevention that exists. Which diet to eat for healthy aging, brain health… it’s total confusion,” he said.
“But at the same time it’s pretty straightforward and simple,” he added. “Eating a high variety of organically grown food that’s not processed and not modified, mostly from plants… is unequivocally the healthiest diet.”