Fermented Food and Gut Health

What is the Gut Microbiome?

The gut microbiome is made up of trillions of microorganisms living in your gastrointestinal tract. The microbiome is mainly made up of bacteria, but also includes protozoa, fungi, viruses and their genetic material. Your gut microbiome plays an important role in metabolism, nutrient absorption, your immune system and the synthesis of vitamins, enzymes and amino acids. Your microbiome also plays a role in many other important processes such as body weight, mood regulation and brain function. Some lifestyle factors such as diet, stress and antibiotics can interrupt your gut microbiome causing dysbiosis.

What is Gut Dysbiosis?

Occasionally the gut microbiome becomes imbalanced, this is called gut dysbiosis. Dysbiosis occurs when there is an alteration of the gut microbiome community resulting in less diversity and decreased numbers. There is some indication that dysbiosis is related to some chronic health conditions such as metabolic syndrome, inflammatory bowel disease, obesity, cardiovascular disease and cancer. Gut dysbiosis can be caused by many factors including illness, obesity, stress, poor diet and antibiotics.

How do I know if my gut is imbalanced?

Many factors of modern life can damage our gut microbiome such as stress, processed foods, high sugar intake, antibiotics and lack of sleep. When the gut microbiome is disturbed it may affect other aspect of our health such as the immune system, weight, nutrient absorption, hormone levels and skin health.

An unhealthy gut microbiome may manifest itself in many different ways. Some common signs of an unhealthy gut include:

Constipation and diarrhea
Gas and bloating
Food intolerance
Sugar cravings
Unintentional weight changes
Skin irritation
Fatigue
Autoimmune conditions
Mood changes

Eating for a Healthy Gut

The gut microbiome benefits the most from a diet high in resistant starch. Resistant starch is a component of dietary fibre which ‘resists’ digestion. Other starches are quickly digested in the small intestine and little survives to pass into the large intestine. However, because resistant starch isn’t digested it makes it into the large intestine providing fuel for the microbiome. This resistant starch is broken down by the bacteria into products which support a healthy digestive system and protect against gut diseases.

It’s important to eat a wide variety of dietary fibres. Different fibres work in different ways and each provide their own health benefits. Eating a variety of fibre, including resistant starch can help to improve gut health and reduce the risk of some diseases. Some good sources of resistant starch include:

Wholegrain cereals
Starchy vegetables
Lentils
Chickpeas
Baked beans
Red kidney beans
Nuts
Firm bananas

Another benefit for gut health is fermented foods. Fermented foods such as sauerkraut, kefir, kimchi, yogurt and miso are excellent dietary sources of probiotics. Although each type of fermented food varies in the amounts and types of bacteria, they all provide benefits for the gut microbiome.

What are the benefits of fermented food for the gut?

Fermentation was historically used as a preservation method; however, this aged-old process provides many benefits for gut health. The benefits of fermented foods and drink go far beyond preservation, the process enhances the nutrient quality and provides a good source of probiotics which are both great for digestive health.

Fermented foods and drinks provide a source of good bacteria which can help with digestion, absorption and assimilations of nutrients. These bacteria also help with the functioning of the immune system and prevents the overgrowth of bad bacteria. When the balance of gut bacteria shifts towards the bad guys, symptoms such as gas, bloating, diarrhea and constipation can arise. This is dysbiosis.

Fermented foods are a rich source of good bacteria and by consuming these foods and drinks you can add beneficial bacteria to your gut helping to increase your gut health and immune system.

Digestion: The process of fermentation breaks down some of the starches, sugars and proteins which means the foods are easier to digest. This can be seen in fermented products which use cows’ milk, the lactose (milk sugar) is broken down into simple sugars which may provide benefits for those who are lactose intolerant, making it easier to digest.

Nutrient absorption: The process of fermentation can help to increase the bioavailability of some nutrients. This helps the body to absorb more of the vitamins and minerals. As well as this, the beneficial bacteria in fermented foods has the ability to manufacture most of the B vitamins, and vitamin K.

Immunity: The majority of the immune system is in the gut. Probiotic foods can help to support the gut lining which helps to support the immune system. When there is a lack of good bacteria in the gut, other forms of bad bacteria may be allowed to grow causing inflammation and compromising the immune system.

Mood: You may have heard about the gut-brain connection. The gut is lined with neurons similar to the brain and is know as the ‘second brain’. While technically it is called the enteric nervous system, your second brain consists of some 100 million neurons! These neurons allow the complicated process of digestion to take place by controlling the gut independently from the brain.

The bacteria in the gut communicate with important neurotransmitters throughout the enteric nervous system and send messages that influence how we feel. This may be good news for those suffering from anxiety or depression, as a change in diet to support the gut microbiome may provide many benefits to mood and mental health.

How long does it take to improve your gut microbiome?

It’s been known for a while that different diets create different kinds of gut flora. One of the most important aspects of improving your gut microbiome is diet. Taking probiotics will only give temporary results if your diet doesn’t support these microbes.

Fermented foods are particularly beneficial for a healthy microbiome. While live yogurt provides benefits, the next step up, such as kefir will provide around five times as many microbes. How long it will take to improve your microbiome will depend on many factors, including health, lifestyle and importantly, diet. However, it doesn’t take long to make positive changes to your gut microbiome by altering your diet to include a wide range of vegetables, fruits, legumes, wholegrains, nuts and seeds. The Mediterranean diet is shown to be very beneficial to gut flora due to its high amounts of fibre and low intake of red meat.