What is the microbiome?
You may not be aware, but there are millions of bacteria living inside your gut. This bacteria is also known as your microbiome or your gut flora. Everyone’s microbiome is unique to them and is shaped by many factors including our genetics and DNA. Studies1 on twins have shown that family members share common gut flora which could affect how much body weight we gain and where we store it.
Our microbiomes are important because they help to keep our immune systems healthy and keep disease at bay. The key is to strike a balance between good and bad bacteria that live in the gut. Researchers2 say that when the bacteria becomes out of balance, it can cause health issues which may lead to an increased risk of conditions like heart disease, cancer and type 2 diabetes.
On the Huffington Post3 blog, Raphael Kellman, MD author of The Microbiome Diet explains: “When your microbiome is balanced, you have a terrific ally that keeps your body healthy, promoting good digestion, clear thinking, balanced mood, and glowing overall health. When your microbiome goes out of balance, however, you risk such symptoms as brain fog, depression, anxiety, bad skin and insomnia — and, down the road, obesity, diabetes, and cancer.”
How does your diet affect the microbiome?
What we eat can have a big impact on the health of our gut and our individual microbiomes can affect our metabolism, digestion and weight. A large study4 in the Netherlands found that everything we drink or eat has an effect on the bacteria living in our digestive systems as well as our overall health. Other evidence5suggests that a diet high in sugar and fat changes the bacteria in the microbiome and leads to obesity.
So, to keep our microbiomes healthy, a varied diet is essential. Researchers6 believe that a diverse diet leads to a diverse microbiome that is able to deal with any bacteria that is harmful to your health.
What is a microbiome diet?
The idea is to eat a diet full of anti-inflammatory foods which helps boost the good bacteria in your gut. Food that lowers inflammation includes:
Fruit and vegetables
Packed with essential vitamins, minerals and dietary fibre, getting your 5 a day is essential for a healthy, balanced microbiome. Aim to fill your plate with a variety of fresh fruit and veg like broccoli, spinach, carrots, blueberries, apples and strawberries.
Herbs and spices
Flavour your food with aromatic spices like ginger and turmeric. Both are known for their anti-inflammatory properties with studies showing that they could help fight inflammation in conditions like rheumatoid arthritis7. Ginger is also commonly used as a herbal medicine to aid digestion and ease nausea.
Foods that contain friendly bacteria may help restore good bacteria in your gut and keep it healthy8. In fact, the Netherlands study found that people who regularly ate yoghurt had more diverse gut bacteria. As well as yoghurt, fermented foods like kefir, miso or kombucha also contain friendly bacteria.
Evidence9 suggests that Omega-3 fatty acids help fight inflammation in the body and may also be used to treat inflammatory bowel disease10. To get your fill, go for oily fish like salmon or tuna, chia seeds or flaxseeds.
According to research11, whole grains aren’t just a nutritious way to provide your body with digestive-friendly fibre. They could also improve the balance of bacteria in your microbiome. Porridge oats or hearty grains like brown rice and quinoa may also keep you feeling fuller for longer.
In moderation, red wine could help keep your microbiome diverse. It contains reservatrol, which one study12 found may lessen the risk of heart disease by adapting the gut microbiome.
What foods should you avoid on a microbiome diet?
Although a small glass of red wine just a few times a week may not do any harm, research13 shows that drinking excessively or for long periods may affect the microbiome which could, in turn, lead to liver disease.
Evidence shows14 that eating refined carbohydrates on a regular basis could have an inflammatory effect on the body. Instead, cut down on white bread and pasta in favour of whole grains.
Research15 suggests that processed food that contains hydrogenated (trans) fat may cause inflammation. These foods are also often high in calories, which may decrease the diversity of our gut bacteria.4
Making some changes to your diet helps support your microbiome, but remember that there is no “one size fits all” approach. “But there is a good correlation between diversity and health: greater diversity is better,” researcher Alexandra Zhernakova MD PhD says. And Dr Kelleman agrees: “The key is to keep supporting your little friends inside — your microbiome.”