The Bio-Fermentary / 01A: The Fundamentals of Gut Health / 01B: Factors that Impact Gut Health

Factors that Impact
Gut Health

Understanding the factors that can influence our gut health is key in order to experience optimal health, beauty and wellbeing.


‘Beauty begins in the belly®’ is the cornerstone of The Beauty Chef philosophy and embraces the concept of food as medicine. Each day, more and more research comes to the fore highlighting how what we eat, the state of our gut and our overall wellbeing are intimately linked.

“What we choose to eat can either help to heal our gut or harm it.”
– Carla Oates, The Beauty Chef Gut Guide

“What we choose to eat can either help to heal our gut or harm it.”
– Carla Oates, The Beauty Chef Gut Guide

Refined sugars, flours, highly processed foods, additives and preservatives can be harmful to the gut. But foods that are difficult to digest are also problematic and can trigger an immune response in some people. Common culprits include gluten32, dairy33, corn and soy – so if you’re experiencing gut health issues, avoiding these substances for a period of time can often be beneficial in order to see if they are a trigger for you (read more about this in The Beauty Chef Gut Guide).

While what we eat undoubtedly influences our microbes – the way we eat is also important so take into consideration how often you’re eating, whether you’re overeating and if you’re feeling stressed.

“If you’re stressed, it is likely your microbiome is too.” – Carla Oates, The Beauty Chef Gut Guide

Again, it’s essential for us to care for our gut in the same way we would a garden, nourishing it with an abundance of nutrient-dense wholefoods to foster microbial diversity while avoiding common allergenic inflammatory triggers. Although we’ve touched on some of the foods that can be harmful, there are a number of foods and nutrients that are particularly beneficial for us to include in our diet.


Traditionally, prebiotics are described as the non-digestible plant fibres – found in fruits and vegetables such as bananas, onions, garlic, leeks, asparagus, artichokes and some legumes – which feed and encourage the proliferation of probiotic bacteria in our gut, while also reducing the amount of pathogenic species and strains in the colon34,35,36. But some research has also explored the prebiotic-activity of polyphenols, compounds which are found in plants. For example, research suggests that consuming antioxidant and polyphenol-rich cacao, may support the growth of Lactobacillus and Bifidobacterium37. Fibre and polyphenol-rich wholefoods are known to feed the microbiome so again, a diverse diet means a diversity of microbes.


Probiotics are the live, beneficial bacteria we consume – either through foods or supplements – and a growing body of research continues to highlight their health benefits38. What do probiotics do? Well, there are some studies, that show how some probiotic species and strains may be beneficial in the management of – and even prevention of – gut issues such as irritable bowel syndrome (IBS)39,40,41 and skin conditions including eczema and dermatitis42,43.

Probiotic supplements: good or bad?

In the same way that there is no ‘one size fits all’ when it comes to diet, the same philosophy applies to probiotics and probiotic supplements. As we know, microbial diversity is the key to optimal gut health so taking a probiotic supplement rich in just one or two strains may not provide adequate probiotic diversity to support your microbiome. Instead, favouring a diverse, nutrient-balanced diet is arguably more beneficial for microbial health.


When it comes to gut health, the realm of ‘postbiotics’ is relatively new, but research is beginning to reveal some exciting health benefits. Essentially, when probiotics in the gut feed on nutrients, the metabolites they leave behind are known as ‘postbiotics’ – and it’s these compounds that studies indicate may play an integral role in our health, supporting our immune system, helping to maintain gut wall integrity and nourishing our microbiome44. While probiotics essentially need to survive digestion and subsequently be fed the optimal prebiotic compounds in order to flourish, there is some research that also explores the beneficial postbiotic activity of non-viable, or ‘dead’, probiotic cells45,46. What all this means is that postbiotics may be just as beneficial for gut health as research suggests they exhibit immune-modulating properties, help to combat inflammation and fight pathogens, as well as improving the integrity of the gut wall47 .

Fermented foods

Fermentation is a method of preserving and adding flavour to food and although it has only recently gained traction as a trend in the health and wellness world, it has been around for thousands of years amongst traditional cultures. At The Beauty Chef, it’s also at the very heart of what we do with the benefits of fermentation going far beyond the nutritional properties of the food itself.

“Put simply, fermentation is a process where bacteria and/or yeasts are used to break down sugars and starches in foods.”
– Carla Oates, The Beauty Chef Gut Guide

“Put simply, fermentation is a process where bacteria and/or yeasts are used to break down sugars and starches in foods.”
– Carla Oates, The Beauty Chef Gut Guide

As a result, fermented foods are easily digested and a rich source of probiotic bacteria48. The fermentation process also supercharges an ingredient's bioavailability49, meaning its nutrients are more easily absorbed and assimilated by the body.

On top of this, postbiotics are also produced during the fermentation process and as discussed earlier, these compounds may be just as beneficial in terms of nourishing our microbiome. We can therefore think of fermented foods as symbiotic – as prebiotics, probiotics and postbiotics work in synergy to support our gut health and overall wellbeing.


Dietary fibre arguably has the most profound impact on our microbes and gut health50. Predominantly found in fruits and vegetables, nuts, seeds and legumes, fibre essentially passes through the small intestine and only begins to ferment once it reached the colon, or large intestine. It is here that fibre begins to work its magic – producing short-chain fatty acids (including acetate, propionate and butyrate) which research shows have anti-inflammatory properties and are integral to our health, supporting our immune, brain and gut health51,52,53.

Different types of fibre

Soluble fibre54 : This type of fibre attracts water and develops into a thick gel, assisting with satiety and slowing digestion. Examples include, oats, psyllium and soaked legumes, beans, nuts and seeds.

Insoluble fibre55: This fibre absorbs water and assists in keeping us regular, bulking out and softening stools. It’s found in whole grains, cruciferous vegetables, onions and unpeeled fruits and vegetables.

Resistant starch: Found in unripe bananas, grains, cooked and cooled potatoes and rice, resistant starch is a type of fibre that ferments in the large intestine and produces short-chain fatty acids. According to research, resistant starch also has probiotic properties which may benefit our gut56.


Just as our food and dietary choices can impact our gut health, so too do our lifestyle choices. As we already know, we are symbiotic beings and every facet of our health and wellbeing is intimately linked. The environments we choose to engage with as well as our response and management of things like stress, are therefore key if we are to maintain optimal health and wellness.


Stress is a complex emotion and although short bouts of stress are normal, unavoidable and even beneficial when we’re presented with a challenging situation – ongoing or chronic stress may therefore have a detrimental effect on our overall wellbeing, as well as our gut health. Research shows that stress not only impacts the balance of bacteria in the gut, but that it can also damage the gut lining itself57 . The impact of stress however, extends far beyond the gut wall, impacting our immune system and skin58,59,60. An influx of cortisol may suppress our immune system function which in turn leaves us more vulnerable to pathogenic bacteria and increases our risk of infection. Cortisol may also contribute to inflammation – both in the gut and beyond. Inflammatory skin conditions such as eczema, rosacea and psoriasis, may therefore be exacerbated in times of stress.

Environmental Toxins

Every day, we’re exposed to a countless collection of chemicals and environmental toxins – in our air, our water, our food, the soil and in our cleaning, beauty and personal care products. While it’s therefore impossible to avoid these toxins entirely, it’s incredibly important to reduce our toxic load as some of these compounds can have a detrimental effect on our gut health and alter the balance and diversity of our gut bacteria. Toxins and moulds in our homes – known as mycotoxins – may also negatively impact our health, contributing to inflammation and allergies.


There’s no doubting the incredible advances in medical research and technology, as well as the power of antibiotics to treat bacterial infections and save lives. However, there is also research to show how antibiotics can alter our bacterial profile61 . While these drugs and medications eliminate the bad bacteria and infections that cause illness, they’re unable to distinguish between good and bad bacteria – wiping out them both. This can mean our gut has a reduced microbial diversity, which is important for our overall health and wellbeing. Over the counter pharmacy products may also have a similar effect on the microbiome.

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