Your allies to take care of your gut microbiota: a varied diet with high-fiber content

“The five superfoods you should eat to stay healthy”, “Coffee is good for your gut microbiota. This is why”. “Impressive health benefits of Kombucha tea for your gut health”. “This diet is really good for your gut microbiota”, and so on and on. Some of these headlines, for sure, ring you a bell. Gut health and nutrition are a hot topic and, now that it is known this is key to overall health, more and more people are interested in eating well and taking good care of their gut microbiota. That can explain why food and nutrition articles on this subject are increasingly common.

Sometimes, though, there is too much information, too often contradictory, lacking scientific evidence and making so much noise in social media that it is difficult to navigate among all those myths, false beliefs and reality.

Danielle Capalino knows it well. This Registered Dietitian Nutritionist in New York City sees people every day in her office that come to see her in search of a magical solution for their gut health problems. “Maybe the biggest misconception I have to deal with frequently is that there is a perfectly healthy gut to have. But there are many ways to be healthy. Even identical twins have 50% the same but 50% different looking guts”, comments this consultant.

It is human wanting to stick to a single easy solution, like “eat this or that and you’ll be healthy”, but there is no such thing as one-diet or food-fits-all solution, Capalino advises. For the moment, the only thing we really know is good for you and your microbiota is fiber. So anything that has fiber, whether it is chia seeds or whole-wheat bread, will be beneficial for you”. Also, prebiotics and fermented milks, like yogurt or kefir, have shown benefits for digestive health.

The recommendations are about 30 g of fiber a day on average -the current Dietary Guidelines for Americans and the US National Academy of Medicine, for instance, recommend adult men 34g per day and adult women 28g, although it depends on their age. But, Capalino, who is the author of “Healthy Gut, Flat Stomach”, advises if you are only eating 10g of fiber right now, you have to gradually increase your fiber intake until you meet the recommended amount.

In case of people with any digestive problems, like bloating, or irritable bowel syndrome Capalino recommends to follow a low FODMAP diet. FODMAPs are foods containing fermentable carbohydrates and some people can be hypersensitive to these carbohydrates and feel uncomfortable due to gas, bloating, diarrhea or constipation after having eaten foods like onions, chickpeas or lettuce.

Eventually, the low FODMAP diet impacts gut microbiota diversity and richness, to obtain the desired effect. That’s why it is not a long-term diet, but a tool to help you identify which foods bother you. “Onions are typically a very problematic food that people might not think of, because often you don’t even see onions in your food when they are integrated in a recipe with other ingredients or really we do not think about it. But they are probably the most common food that I see, especially related to bloating”, she recalls.

But not all the fibers are the same. “I love the term ‘microbiota accessible carbohydrates or MAC. It is a more specific definition than fiber, because not all fibers are accessible by your microbiota. So MAC are the best category of carbohydrates to focus on”, she points out, and puts some examples: apples, oats, whole-wheat, legumes like lentils and beans are MAC.

Animal protein is another group of nutrients to be controlled. You can eat meat, but not every day, and it’s advisable to diversify the types of proteins in nutrition. Cereals and legumes are a vegetable source, for instance. “At the end all of this is about enjoying the widest variety of foods possible, just for your quality of life and your gut microbiota health, and for your comfort”, concludes Capalino, who took part in the Gut Microbiota for Health World Summit, held in Miami (Florida, USA).

 

Cristina Sáez
Cristina Sáez
Cristina Saez is a freelance science journalist. She works for several media, for instance the Spanish newspaper La Vanguardia, where she coordinates the science section, Big Vang; as well as research centres and scientific societies. She has been awarded for her journalistic work, among others, with the Boehringer Ingelheim Award in Medical Journalism 2015. Follow Cristina on Twitter @saez_cristina