Gut Health From North To South: A Functional Nutrition Approach
When it comes to gut health, it’s tempting to skip straight to probiotics, food intolerance tests or cutting out gluten, dairy and everything in between. But it’s so important to remember that digestion and gut health doesn’t actually start in your gut.
Digestion is a top-to-bottom process - starting in your brain and ending, quite literally, at the other end. And when one part of that system gets sluggish, stressed or out of sync, it can cause a knock-on effect further down the line.
In functional nutrition, we call this working North to South. And if you’ve been struggling with bloating, constipation, fatigue, reflux or food sensitivities despite eating “well”, this might be the missing piece.
Let’s walk through the journey and how to support each stage.
1. It starts in the brain and mouth
Digestion kicks off before food even hits your stomach.
Just seeing, smelling, and thinking about food begins to trigger saliva production and digestive enzyme release. It’s called the cephalic phase of digestion and it’s often skipped when we eat distracted, on the go, or under stress.
Try this:
Take a few deep breaths before eating
Look at and smell your food
Chew slowly and thoroughly (aim for 20–30 chews per bite)
2. Stomach acid and pancreatic enzymes
Once food hits the stomach, we need enough stomach acid (HCl) to break down protein, kill pathogens, and signal the release of digestive enzymes from the pancreas. This is a critical step for nutrient absorption.
Low stomach acid = bloating, reflux, burping, nutrient deficiencies, and undigested food fermenting further down.
Support it by:
Avoiding water chugging with meals
Including bitter foods (rocket, lemon, apple cider vinegar)
Managing stress before eating
3. Bile flow & gallbladder health
Bile is released into the small intestine from the gallbladder to help break down fats, encourage absorption of fat-soluble vitamins, support microbial balance, and eliminate toxins. But many people struggle with sluggish bile flow, especially if they’ve had gallbladder issues, eat low-fat diets, or feel nauseous/full after rich meals.
Help it flow by:
Eating healthy fats (in moderation)
Adding bitters (artichoke, dandelion, rocket)
Staying well hydrated
4. Small intestine
This is where most nutrient absorption happens, but it’s also where things can go wrong if the gut lining is inflamed or permeable (aka “leaky gut”). Toxins, undigested food or microbes can trigger immune responses and contribute to sensitivities, fatigue, and systemic inflammation.
Support your gut lining:
Support HCl, pancreatic enzymes, bile flow
Removing inflammatory triggers (e.g. excess alcohol, stress, processed foods)
Eating a varied, colourful, wholefood diet
Zinc, omega-3s, slippery elm, collagen, bone broth
5. Fibre & prebiotics = food for your microbes
Once food reaches the large intestine, it’s fermented by your gut bacteria. Fibre and prebiotic-rich foods are key for feeding beneficial microbes, producing short-chain fatty acids (like butyrate), and keeping your bowel movements regular.
Try:
Cooked and cooled potatoes (resistant starch)
Oats, legumes, flaxseeds, chia seeds (soluble fibre)
Onions, garlic, asparagus, leeks, apples (prebiotics)
6. Probiotics & microbial balance
Now we’re at the microbiome! This diverse community of bacteria influences everything from immunity and metabolism to mood and skin health. But if the earlier steps aren’t working, probiotics alone won’t fix things.
Include:
Fermented foods (kefir, kimchi, live yoghurt, sauerkraut)
Diverse plant foods (aim for 30+ types a week!)
High-quality targeted probiotic supplements if needed
7. Excretion: the final step
Last but not least: elimination. Your bowel movements are a key detox pathway, clearing out waste, toxins and excess hormones. If you’re not going regularly, it can affect everything from skin to energy to mood.
Support this by:
Staying hydrated
Moving your body
Eating enough fibre and healthy fats
Optimising your toilet position with a foot stool
Why this all matters
When clients come to me with persistent gut symptoms, even though they’re eating clean or taking all the right supplements, we often find that one of these foundational steps is being skipped.
That’s why I always look at digestion as a whole system. Start at the top. Tune into your body. Work North to South.
Simple shifts can make a big difference.
Working on your gut?
You don’t have to figure it all out alone. I work 1:1 with clients to identify where the imbalances are and tailor realistic, enjoyable changes that work with your lifestyle. Book a free call and let’s chat things through.