The case for beans and whole grains for gut health and longevity was made emphatically by dietitians, doctors and researchers gathered at a top nutrition conference, with fibre emerging as the single nutrient they most want people to prioritise. Business Insider spoke to more than a dozen nutrition specialists at the event, and two foods came up again and again: beans and whole grains.
Why fibre is the thread connecting beans and whole grains gut health benefits
Both foods are high in fibre, a nutrient that can help regulate blood sugar, manage appetite and protect against heart disease and cancer. Hannah Kittrel, a Ph.D. candidate at Icahn School of Medicine at Mount Sinai, offered the plainest possible directive: ‘Get more fiber. I don’t care where you get it from, as long as it’s whole foods and not a soda or something.’
The point about whole grains deserves unpacking, given the persistent cultural anxiety around carbohydrates. Not all carbs behave the same way. Ultra-processed carbs can spike blood sugar and fuel cravings, but minimally processed grains (oats, quinoa, brown rice) do the opposite. They contain B vitamins, fibre, protein and minerals including magnesium, all housed in the outer layers of the grain. When grains are processed, those layers are stripped away to create a smoother texture and milder flavour, and the nutrients go with them.
Left intact, whole grains take more energy to digest, which means a slower, more stable rise in blood sugar and a longer feeling of fullness. The additional plant material also feeds beneficial bacteria in the digestive system, which help protect against disease. Marian Neuhouser, who studies diet and cancer risk at the Fred Hutchinson Cancer Center, put it directly: ‘There’s a real fear of carbohydrates right now, but we need whole grains to keep the gut healthy.’
Neuhouser leads Fred Hutch’s Cancer Prevention Programme, the first National Cancer Institute-funded programme of its kind in the United States, which gives particular weight to her position on whole grains and cancer risk.
Beans: the everyday longevity food that dietitians eat themselves
Beans sit alongside whole grains as the other consensus pick. Nicholas Marchello, a registered dietitian and nutrition professor at the University of Central Missouri, was candid about his own habits: ‘Not to brag, but I eat beans almost every day. There are so many health benefits to beans.’ Some of the longest-living people on Earth centre their meals around beans, and researchers suggest eating at least a cup daily for a longer life.
Beans are packed with fibre, potassium, iron and folate, and are also a good source of protein, one that the dietitians at the conference rated above ultra-processed protein isolates such as protein bars or shakes. Pairing beans with whole grains creates a complete protein source, providing all the essential amino acids needed to build muscle and support healthy cells.
Sports dietitian Leslie Bonci highlighted how practical beans are across a wide range of meals, from soups and sauces to pasta, dips and stir-fry. ‘They’re affordable and versatile,’ she told Business Insider, ‘and you can use the can for bicep curls.’ The beans-and-whole-grains combination also addresses what Marchello and others see as a serious public health gap: most people are simply not consuming enough fibre.
The recommendation to broaden plant variety beyond just these two foods also featured prominently. Synneva Hagen-Lillevik, a dietitian and post-doctoral fellow at the University of Colorado Denver, made the case for diversity in plant foods on two grounds: different plants offer distinct benefits for gut bacteria, and variety tends to crowd out less nutritious options. ‘The variety of plant foods is important for your gut health, and you’re less likely to eat other things,’ she said.
For anyone looking to start, the message from the conference is consistent: add beans and whole grains, broaden the range of plants on the plate, and let fibre do the work. Neuhouser’s Cancer Prevention Programme continues to examine precisely how those dietary patterns translate into reduced cancer risk, a line of research that should yield further evidence in the years ahead.