Let’s talk about a very exciting topic that is gaining popularity recently – Gut Health. Specifically, gut health and weight loss.
Your digestive system is at the centre of your wellbeing and involved in so many vital processes. It’s main responsibility is converting food into simple nutrients and delivering them to the body via the bloodstream. The food we eat is an essential energy source for the cells in our body. Unlike plants who harness energy from the sun, we get our energy second hand from plants or animals that eat plants.
But your gut does more than digest your food. Your gut also plays a role in signaling your immune system, regulating your hormones and even influences your mental health. It does these things through something call the gut microbiome. A community of microorganisms that live in your gut.
There are about 100 trillion bacterial cells that live with us in what we call a symbiotic relationship. Meaning, they benefit from us and we benefit from them. When you compare the large number of them with the only 35 trillion cells that make up the entire human body, they aren’t really our bacteria. Instead, we are their human and they have a significant influence over our health and wellbeing.
So how do they provide this influence? Well, they ferment (or eat), any undigested food that makes its way to the large intestine. This is usually fibre, excess protein and simple sugars like lactose or fructose. As a result of the fermentation of these foods, they produce a large and diverse number of small molecules called metabolites. Some of these are beneficial to us in signalling our immune system or producing mood-enhancing neurotransmitters. While others can be inflammatory and contribute to disease. This depends on the type of bacteria producing them and the food being fermented. The most beneficial metabolites come from bacteria that like to eat fibre.
The key to having a healthy gut is having a large and diverse community of bacteria living there. This diversity is different for each person. It is determined by our genetics, the way we were born (either by natural delivery or c-section) and the foods we eat. A healthy balance between fibre loving and protein eating bacteria is what makes up a healthy microbiome. All of the research now is starting to point to an imbalance in our bacterial communities as a leading cause for many chronic diseases, and even your ability to manage your weight.
Fibre loving vs protein loving bacteria
The two main groups of bacteria that make up your intestinal microbiome are the Fermicutes [ferm-i-cute-ies] and the Bacteroidetes [bac-ter-oid-et-ies].
Now, don’t let the names fool you though – the firmicutes aren’t the cute ones. The firmicutes prefer a diet that is higher in animal proteins and the Bacteroidetes prefer a diet that is higher in fibre. Most studies show that the more Bacteroidetes you have compared to the firmicutes, the less overweight you will be.
This is due to two main reasons:
- Bacteroidetes bacteria produce metabolites called short-chain fatty acids. They’re produced from the breakdown of fibre in the large intestine and play an important role in the metabolism of carbohydrate and fat. They also influence the production of hormones that make you feel full and satisfied.
- The metabolites that the firmicutes bacteria produce from the fermentation of excessive protein, promote inflammation in the body and can make you more resistant to the hormone insulin. This will make your body store more fat and make it more difficult lose weight.
The bacterial diversity in your gut also has the ability to influence your mood. For some people, this is a trigger for overeating. Here’s how it works:
There are chemicals in your body called neurotransmitters. They control your feelings and emotions. They’re mostly made by your brain, but they’re also made by the cells that line your gut and the metabolites of your gut bacteria.
70% of your body’s serotonin, a neurotransmitter that contributes to feelings of happiness, is made in your gut. The neurotransmitter GABA, which helps to reduce feelings of fear and anxiety, is produced by the fibre loving Bacteroidetes bacteria.
So, if you have a diet that is low in fibre and higher in animal protein, you’re going to have fewer bacteria to produce substances to help you control your weight and more bacteria that will make you store more fat.
So, what are the best foods for gut health and weight loss?
Fiber, first and foremost fiber!
- Make at least half of the grains that you eat everyday whole grains – oats, quinoa, buckwheat, rice, barley, whole wheat.
- Eat lots of fruits and vegetables and make sure you eat the skin wherever you can. This has got lots of good fiber in it.
- Nuts and seeds are excellent sources of fiber, as well as legumes. Your gut bugs will just love them.
- The other thing that your gut bugs love to eat is these polyphenols. These are an antioxidant in plant-based foods. They also have an anti-inflammatory effect within the body. Olive oil, dark chocolate, green tea, and red wine are all excellent sources of polyphenols.
- The other thing that you can do is include fermented foods within your diet daily. These are foods that have had beneficial bacteria added to them. When you eat these fermented foods, you eat the beneficial bacteria. This helps to colonize your gut with lots of really beneficial bacterial strains, just to continue to improve the diversity. Natural yogurts, kombucha, kefir, sourdough bread, kimchi, and sauerkraut are easy foods to introduce first.
Which foods are worst for gut health and weight loss?
High sugar foods or a diet that is high in added sugar (more than six teaspoons of added sugar each day) will disturb the balance of bacteria in your gut. Added sugar is food that has had sugar added to it. Think, adding sugar to your tea or coffee, buying packaged foods that have had glucose, corn or fructose syrup, or just normal sucrose added into them. It’s not the sugar that we find naturally in our grains, fruits, vegetables, and dairy products. Artificial sweeteners are also harmful to the bacteria in your gut. So it’s a good idea to avoid them wherever you can.
Excessive amounts of saturated fat isn’t great for your gut health. We find this type of fat in the animal foods that we eat, but also some of the plant foods, like coconut and palm oil. Eating too much saturated fat, ie. more than 10% of your daily energy intake, disturbs the balance of your intestinal microbiome. So when you’re eating your favourite animal foods, choose lean meats, take the skin off the chicken, don’t consume excessive amounts of milk or cheese, and avoid too many processed and packaged foods.
Researchers have demonstrated that even if your diet goes off track for just three days, it will significantly alter the health of your gut microbiome. So it really is about consistency, wherever you can. On the flip side, the good news is that in just a couple of days, you can really turn things around. But if you really want to optimise your gut health for weight loss, it’s the consistency that you need.