Your Microbiome and it’s potential effect on obesity
It is often a surprise to people when I tell them, we have as many bacterial cells in our body as we do human cells. That’s right, for every human cell in the body, we have a bacterial cell. It used to be believed we had 10 bacterial cells for every human cell, but new evidence and the inclusion of red blood cells as cells has changed this.(1)
However that is still a huge amount, in fact, it means we have around 40 trillion bacterial cells in our bodies, depending on our own size and weight. This is a huge number and unsurprisingly our bacterial ecosystem has a huge effect on our own health and wellness. Interestingly according to emerging research, potentially also on our waistline.
It turns out although what we eat, how much exercise we do and a few other factors all impact our likelihood of becoming overweight. So does our diverse ecosystem of bacteria.
When scientists compare the bacteria of obese humans and lean humans, we see quite a different variety of bacteria. It is likely this is in part due to different diets and lifestyles. As a diet low in fibre and carbohydrates can change our bacterial balance and diversity.
A diet high in refined carbohydrate, processed fats and low in fruits and vegetables changes our bacteria balance. Since our bacteria thrive on a diet rich in fibre.
Even with this being the case, studies in mice have shown it is more than just correlation. Our internal ecosystem of bacteria really can affect our weight (at least in mice anyway).
To test whether gut bacteria can cause weight-gain. Researchers raised genetically identical baby mice in a germ-free environment. As their bodies would be free of any bacteria.
Then they populated them with intestinal bacteria collected from obese women and their lean twin sisters. The mice ate the same diet in equal amounts. Incredibly though animals that received bacteria from an obese twin grew heavier and had more body fat than mice with microbes from a thin twin. As expected, the fat mice also had a less diverse community of bacteria.
The researchers then repeated this experiment, but with one small twist. The mice populated with obese women’s bacteria were put in the same cage as the mice populated with lean women’s bacteria. This time the mice did not become obese. Instead they managed to pick up the bacteria residing in the lean mice, probably because mice eat each other’s feces.
These novel studies make it quite clear. The bacteria that reside within us have a cause and effect relationship on weight or at least they do in mice.
It is still very early days for this area of research, but our bacteria clearly have a huge effect on us and potentially on our weight. Studies are showing certain bacteria can have affects on our hunger hormones. The way we metabolise certain foods for energy and even on our ability to build muscle.
Putting all this together, it soon becomes clear we should be doing everything possible to create a prolific and diverse bacterial ecosystem within our bodies.
How to make your gut Healthy
So how do do this? Well unfortunately some of the initial work is done very early in life. During birth we get our first dose of bacteria while passing through the birth canal, unless we are delivered by C-section. Next it’s whether we are breastfed as this delivers beneficial bacteria to start the initial bacteria we will develop throughout our lives.
After this it depends on our exposure to antibiotics. Especially early in life as these will destroy not only the bad bacteria making us sick, but also much of our beneficial bacteria. Dr Dominguez-Bello says. “Antibiotics are like a fire in the forest,” “The baby is forming a forest. If you have a fire in a forest that is new, you get extinction.”
Although all of the above factors are completely unchangeable for you now. There are many things you can do to help improve your bacterial balance and help prevent weight-gain.
Most of it comes down to diet and supplements. Surprisingly though management of stress is also important. It turns out during periods of stress our gut bacteria become less diverse and higher in potentially harmful bacteria.(3)
To help improve our bacteria there are a variety of ideas as this is still an emerging area of study. Research is hoping to eventually develop the ability to test the amount and diversity of our bacteria. Then prescribe the bacteria we need most to help rebalance it. However even if this was to develop in the near future, dietary changes to maintain this balance would still be essential.
However the above option doesn’t exist. Instead we have to try and cover all basis to create the best situation for beneficial bacteria to thrive in.
Luckily for us, most of the things required for healthy weight-loss also help create a healthy diverse microbiome.
Check out article two here on how we focus on creating a healthy gut.