Research indicates that dysbiosis, or imbalance in the microflora of the gut, can affect all kinds of health problems: metabolic diseases such as obesity and diabetes, cardiovascular disease, immune and endocrine disorders, cancer, bone disease, circulatory problems and even cognitive – aging and Alzheimer’s disease.
The trillions of microbes in your gut, therefore, play an active role in your overall health, meaning what you feed your resident insects matters. Establishing healthy eating habits may even be more important to gut health as you age, research from the National Institute on Aging suggests.
“As people get older, there tends to be more use of drugs, which can have a damaging effect on the gut,” Sydney Greene, MS, RDN, a member of our board of medical experts.
Here are some dietitian-approved tips on maintaining a healthy gut as you age, and for more gut health advice, here’s what the science has to say about popular foods that can improve gut health.
The trick to bringing the gut back into balance throughout life is establishing microbiome-friendly eating habits, starting with fertilizing the gut with fiber.
“It is important to consume high-fiber grains, fruits and vegetables to optimize gut health,” says Greene.
Fiber is the fuel that feeds bacteria so it can grow in number and become more diverse. A large and diverse population of microbes creates a thick mucus barrier lining our gut, which reduces inflammation throughout the body and protects against toxins that escape from the gut wall, a syndrome called “leaky gut”.
Reducing the consumption of refined flour products and sugars from snacks and drinks goes hand in hand with the consumption of whole foods higher in fiber. Get in the habit of skipping white bread and baked goods as much as possible as you switch to more complex carbohydrates like whole oats, quinoa, brown rice, and sweet potatoes, says Laura Krauza, MS, RDN, of Waistline Dietitian.
While you’re getting into the habit of eating higher-fiber foods, work on some foods that have been naturally fermented. Microbes thrive in preserved foods such as sauerkraut, naturally fermented pickles, kimchi, kefir, and yogurt.
“I recommend adding at least one probiotic-rich food to your diet per day,” says Greene.
They provide an influx of beneficial probiotics while lowering the pH of the gut, making it inhospitable to bad bacteria.
For a more detailed explanation, here’s what happens to you when you eat fermented foods.
You may have heard of this provocative carbohydrate called resistant starch. It earns its reputation by resisting digestion in the small intestine and moving along the large intestine where its fibers ferment into a prebiotic that feeds the good bacteria in the gut.
“This is really important for our immune system and also to help us stay lean,” says gut health expert Kara Landau, RD and founder of Uplift Food. “Fermentation byproducts help improve insulin response and reduce the accumulation of fat around the waist.”
Resistant starch is found in grains that have been cooked and then cooled such as lentils, legumes, legumes such as white beans and green bananas. Landau also recommends using resistant starch flour in cooking.
We’re sure you’re familiar with the probiotic benefits of yogurt. You may also know that yogurt is especially good for boosting health-promoting Lactobacillus species. But did you know that cheese is another good dairy source of gut bacteria?
“Cheese is good for the gut; it has its own microbiome, the result of its starter culture,” says William W. Li, MD, author of Eat to Beat Illness: The New Science of How Your Body Can Heal Itself.
Parmigiano-Reggiano, the famous hard cheese from Parma, Italy, is rich in Lactobacillus casei and Lactobacillus rhamnosus, which studies say may be useful against gastroenteritis, diabetes, obesity and cancer, says Dr. Li.
“Eating meat is difficult for your microbiome,” says Dr. Li.
Why? Well, that’s pretty simple. The more animal protein you eat, the less room there is in your diet for plant foods that provide the dietary fiber your microbiome needs. Less fiber leads to an unhealthy ecosystem of gut bacteria.
“More animal protein moves bacteria to behave in ways that generate more gut inflammation,” he says.
By consuming less meat, you can reduce the harmful effects of inflammation. And because many meat products are highly processed, they contain chemical food additives and preservatives that destroy health-promoting bacteria.
Another strategy for promoting a healthier gut microbiome may not necessarily have to do with what you eat, but when and how often. A study on the diary Nutrients explored how meal frequency and fasting can affect the composition of bacteria in the gut.
The results point to the same health benefits that studies show for having breakfast, consuming most of the calories in the early hours of the day compared to the night and fasting, which means reducing inflammation, improving cell regeneration and reducing gastrointestinal stress.
Furthermore, the researchers found a significant addition: increased microbial diversity in the gut, the hallmark of a healthy microbiome in the intestinal tract.
For more information on how fasting can help your health, here’s how intermittent fasting can lead to “significant” weight loss.