Home  /  Library  /  Nutrition

Nutrition

You Are What You Digest: A Complete Guide to Gut Health

Your gut talks to your mood, your skin and your hormones. Here is how to listen, and how to help.

By Brydee Thomas4 August 202611 min read

There is an old naturopathic saying that has stayed with me for years: you are what you digest, what you absorb, and what you do not excrete. It sounds almost too simple to be profound, yet the more you understand your gut, the more you realise how true it is. This is a gentle guide to how to improve gut health naturally, without overwhelm and without doing everything at once.

Your gut is not just where food becomes fuel. It is home to trillions of microbes, around seventy per cent of your immune system, a network of nerves often called your second brain, and even a set of bacteria that help regulate your hormones. When your gut is happy, so much else quietly falls into place: energy, mood, skin, immunity, hormonal balance. The gut-skin link in particular is worth knowing about if you are looking for foods that genuinely help your skin. When it is not, you feel it everywhere. So let’s take a proper look at what is happening in there, and how to gently support it.

The journey of your food

Digestion is a beautiful relay. Each part of the digestive tract has its own job, and hands the baton smoothly to the next, and understanding that journey makes it much easier to see where things flow well, and where they can get stuck.

It starts, believe it or not, in your mouth. Chewing is real digestion, not just a formality before the interesting part begins. It physically breaks food down, and your saliva starts digesting carbohydrates before anything has even reached your stomach. Eating slowly, and chewing properly, genuinely sets the whole process up to succeed.

From there, food travels to your stomach, which churns it with powerful acid that kills off pathogens, unlocks minerals like iron, activates enzymes and starts breaking down protein. Good stomach acid is protective, not something to fear or suppress.

Next comes the small intestine, the real star of the show. Around ninety per cent of all nutrient absorption happens here, across a surface folded into millions of tiny finger-like villi. Enzymes from your pancreas and bile from your liver finish the job.

Whatever is left travels on to your large intestine, home to your microbiome. Here, trillions of bacteria ferment the fibre you could not digest yourself, manufacture certain vitamins, and water is reabsorbed as your stool is formed.

And quietly, behind the scenes, everything you absorb travels first to your liver, which filters and detoxifies it before it reaches the rest of your body. A constant, unglamorous guardian, working away without ever asking for credit.

When any stage of this relay is rushed or under-supported, whether that is eating on the go, low stomach acid, too little fibre or a stressed nervous system, the whole system feels the effects. The good news is that each stage also responds beautifully to a little care.

More than just digestion

Here is where it gets genuinely fascinating. Your gut is in constant conversation with the rest of your body, and three particular connections matter most, each one linking to other parts of your wellbeing you may already be thinking about.

The first is the gut-immune connection. Around seventy per cent of your immune system lives in the wall of your gut, which makes sense: the gut is where the outside world, your food, meets the inside of your body, so it is constantly meeting and learning from microbes. Your gut lining and its bacteria form a crucial first line of defence, which is exactly why looking after your gut is one of the most powerful things you can do for your immunity.

The second is the gut-brain connection, and this one tends to surprise people. Your gut contains around one hundred million nerve cells, a network so rich it is nicknamed the second brain, wired directly to your actual brain. Digestion runs best in rest and digest mode; under stress, the body dials digestion down. Remarkably, around ninety per cent of your body’s serotonin, a key mood chemical, is made in the gut, and your microbes help produce the building blocks for it. A calmer nervous system and a well-fed gut genuinely support a steadier mood.

And the third connection links straight back to your cycle: the gut-hormone connection. A specialised group of gut bacteria, known as the estrobolome, helps regulate oestrogen. After your liver processes used oestrogen and sends it to the gut to be cleared, these bacteria influence how much is escorted out versus reactivated and sent back into circulation. When the gut is balanced, this runs smoothly; when sluggish or imbalanced, for example after antibiotics or with constipation, used hormones can be reabsorbed rather than cleared. A healthy gut is quietly part of hormone balance.

Meet your microbiome

Your large intestine is home to more than one hundred trillion bacteria, collectively your microbiome. Far from being passive passengers, they finish extracting nutrients, manufacture certain vitamins, crowd out troublesome bacteria and train your immune system. A diverse, well-fed microbiome is one of the strongest foundations of good health, and the single biggest lever you have over it is what you eat.

There are three groups of foods worth knowing here. Probiotics are the bacteria themselves, live cultures in fermented foods like yoghurt with live cultures, kefir, sauerkraut, kimchi, miso and tempeh. A little, often, is the way in. Prebiotics are the special fibres that feed your good microbes, found in garlic, onions, leeks, Jerusalem artichokes, oats, slightly-cooled cooked potato, bananas, apples and legumes. And polyphenols are the bonus fuel, colourful plant compounds your microbes love, found in berries, herbs and spices, olive oil, green tea and a little dark chocolate.

But if there is one golden rule that matters more than any single food, it is diversity. Different microbes eat different fibres, so the more varied your plants, the more resilient your microbiome. The American Gut Project, one of the largest microbiome studies ever conducted, found the single strongest predictor of a healthy, diverse gut was not any supplement or superfood, but simply the number of different plant foods eaten weekly, with thirty or more the sweet spot. Plants count widely: vegetables, fruit, wholegrains, legumes, nuts, seeds, herbs and spices all add to your tally.

Aiming for thirty or more different plants a week is a target, not a test, and variety matters more than any single food. Most of us fall short of the roughly thirty grams of fibre a day that supports the gut, so wholegrains, legumes, fruit and vegetables all help gently. Little wins add up too: a sprinkle of mixed seeds, a handful of herbs, a different vegetable in the trolley each week. And go slowly if increasing from a lower baseline, building up with plenty of water, as a sudden jump can cause bloating while your gut adjusts.

When you care for your gut, you are caring for so much more than digestion.

Signs your gut needs a little love

Your gut is good at telling you when something is off. The trick is learning to listen. Here are the most common signals, and the gentle, food-first responses that tend to help.

Bloating and wind often respond well to slowing down and chewing thoroughly, keeping meals unrushed, and going gently on very large or processed meals. Ginger, fennel and peppermint teas can soothe, and building fibre up gradually helps too. Constipation usually benefits from more fibre from wholegrains, fruit, vegetables and legumes, plenty of water, movement, and natural helpers like prunes, figs, flaxseeds and magnesium-rich foods. This is exactly why magnesium is so often low, even when your diet is good. A sluggish bowel is worth nudging, as it also affects hormone clearance.

Sluggish or stressed digestion often comes back to the brain-gut link. Eating away from screens and stress, a few slow breaths before eating, and calm, unrushed meals all invite that rest and digest state.

Reflux or heartburn tends to respond to smaller meals, finishing eating three to four hours before bed, not lying down straight after eating, and drinking between rather than during meals. Easing off coffee, alcohol and rich food often helps.

Reacting to certain foods is worth approaching gently, noticing patterns rather than cutting many things at once. Common triggers include dairy and gluten-containing grains, but a calm, tracked trial beats a dramatic overhaul.

Running beneath all of these is one recurring theme: stress is a genuine digestive factor, not all in your head. Because the gut and nervous system are so wired together, calming your nervous system is one of the most underrated ways to help digestion.

How to love your gut, day to day

You do not need a complicated protocol, just a handful of steady habits that, repeated, transform how your gut feels over time.

Chew, and slow down. Digestion begins in the mouth and works best when you are calm, so chewing thoroughly and eating away from stress lets your body drop into rest and digest, arguably the highest-impact, lowest-cost habit here.

Eat the rainbow, aiming for thirty or more different plants a week. Different veg, fruit, wholegrains, legumes, nuts, seeds, herbs and spices all count.

Build fibre gently, working towards around thirty grams a day from whole foods, increasing slowly with plenty of water.

Add a little fermented food, often. A spoon of sauerkraut, a small glass of kefir, live yoghurt, miso or kimchi, in small regular amounts, helps diversify your microbiome.

Include prebiotic foods. Garlic, onions, leeks, oats, apples, slightly-cooled potato and legumes feed your good bacteria.

Hydrate and move. Water keeps things moving; gentle daily movement, even a walk, stimulates the muscular waves that carry food through the gut.

Tend to stress and sleep. Because of the gut-brain link, calming your nervous system and sleeping well are genuine digestive support, not extras.

A gentle reminder

Your gut is remarkably responsive. It is renewing and rebalancing itself all the time, which means small, consistent kindnesses genuinely add up.

You do not need to overhaul everything or eat perfectly. A little more variety, a little more fibre, a few calm meals, a spoon of something fermented: these are the quiet habits that change how your gut, and therefore how you, feel over the weeks and months.

And remember how connected it all is. A happier gut supports steadier energy, calmer mood, stronger immunity and more balanced hormones. When you care for your gut, you are caring for so much more than digestion.

If you would like to keep going, blood sugar balance sits right alongside this, eating with your cycle shows how to adapt it month to month, and the right herbal teas can soothe digestion beautifully. If you are newly postpartum, the first poo after birth covers what helps in those first tender weeks. If you are pregnant, heartburn in pregnancy covers reflux specifically and what genuinely eases it. If you would like this tailored to you, this is how I work with women.

Written by

Brydee Thomas

Holistic health coach and founder of Radiant Bloom, supporting women through trying to conceive, pregnancy and the postpartum months. Evidence-based guidance, no programmes and no generic plans.