My daughter asked me the other day exactly what the 'gut' is, so before we start, let's start with that.
In nutritional medicine, when we say 'gut' we generally mean the bowel. While the entire digestive tract and indeed, the entire body, is teeming with bacteria, when practitioners speak of gut bacteria, we're mostly speaking about the bowel because:
It has vastly higher numbers of bacteria than other parts of the digestive system.
Bacteria in the bowel are extremely biologically active, constantly producing compounds that affect health throughout the body, not just in the gut.
Bacteria in the bowel are prone to imbalance. We call this 'dysbiosis' and it's present in almost all modern diseases.
Bacteria in the bowel are modifiable and highly responsive to diet and lifestyle.
That last point is the exciting part because even though it's relatively new science, we know so much about how we can improve our gut bacteria and how that in turn improves our health.
Before we look at how to do that, let's have a quick look at conditions linked with poor gut bacterial balance:
Inflammatory bowel disease & Irritable bowel syndrome
Coeliac & other auto-immune diseases
Type 2 diabetes
Non-alcoholic fatty liver disease
High blood pressure and cardiovascular disease
Stress response, anxiety and depression
Central nervous system and behavioural disorders including ASD, Parksinsons and Dementia
(See references below).
That's a scary list, right? That's why it's SO important to get your gut bacteria in a good and healthy balance.
The good news is the gut microbes are super responsive to what you take in. They can literally change after just one meal!
For some people, and in some conditions improvements from diet & lifestyle changes are seen and felt in as little as 3-4 days.
And it's not as hard as you think. There's SO MUCH you can do to improve your gut bacterial balance every day.
Everyone probably knows about eating probiotic rich foods to help (yoghurt, kefir, kombucha, sauerkraut*), but there are other things you can do to cultivate healthy gut bacteria that aren't so widely known.
Here are 5 ways to improve your gut bacteria that might surprise you:
1. Eat a wide variety of in season local fruits and vegetables
The more variety of fruits and vegetables you eat, the more variety of microbes will grow in your gut. In most of the conditions listed above, low bacterial variety is part of the problem. Exposure to microbes from in-season, local fruit and vegetables is thought to be even more helpful as they give your internal body exposure to your external environment, which may have protective and adaptive benefits.
2. Eat nuts, seeds and whole grains daily
Nuts (with skin on) plus seeds and whole grains give your body a broad range of prebiotic fibres that feed gut bacteria. Prebiotic fibre from plant foods support the growth of favourable gut bacteria; the kind that produce beneficial health compounds. As these bacteria grow, they overpower less desirable bacteria and create a healthier overall gut environment. Good examples are walnuts, almonds, chia seeds, flaxseeds, barley, oats. If you have trouble digesting these, soak them first.*
3. Spend more time in nature
This you might find really surprising. When we're in nature, we're breathing in microbes from the trees, plants and soil around us. This is useful for producing diversity in our internal microbial environment and funnily enough can help us adapt better to our external surrounds. So get out into the bush or garden and breathe in the fresh air and the microbes!
4. Stop disinfecting everything
While it's important to stop the spread of some germs and some bacteria, humans have and always will exist alongside microbes. As noted, we are partially made up of bacteria, many of which work in our favour. Disinfecting everything means killing off harmful bugs, but also ones that help us. It reduces our exposure to variety and diversity of bacteria. So wash hands yes, but be mindful of over-sanitising.
5. De-stress, unwind and relax
Chronic, long term stress, can obliterate gut microbes and dramatically change the environment of your gut. It's a chicken and egg scenario, because poor gut health can be a cause of mood concerns such as anxiety and depression, but those in turn reduce gut bacterial health. Self care, rest and other stress management strategies are an essential part of maintaining healthy gut bacteria.
Ten years ago we barely knew anything about gut health. Now we know so much it's becoming hard to ignore, and we're learning more every day. Hopefully this article has given you some more insight, knowledge and tools to help your bacterial garden grow better.
*Please note, if your gut is currently inflamed or IBS/IBD or other digestive issues are present, some foods might be making you feel worse. Reach out if you need help with that.
Madhogaria, B., Bhowmik, P., & Kundu, A. (2022). Correlation between human gut microbiome and diseases. Infectious Medicine, 1(3), 180–191. https://doi.org/10.1016/j.imj.2022.08.004
Thursby, E., & Juge, N. (2017). Introduction to the human gut microbiota. Biochemical Journal, 474(11), 1823–1836. https://doi.org/10.1042/bcj20160510
Vijay, A., & Valdes, A. M. (2021a). Role of the gut microbiome in chronic diseases: A narrative review. European Journal of Clinical Nutrition, 76(4), 489–501. https://doi.org/10.1038/s41430-021-00991-6
Valdes A M, Walter J, Segal E, Spector T D. Role of the gut microbiota in nutrition and health BMJ 2018; 361 :k2179 doi:10.1136/bmj.k2179