5 “healthy” exercise supplements that are ruining your gut
Kaya KozaneckaWritten on 13th March
With our founder, Niall, tackling his first 52km ultramarathon this Saturday, in hopes of becoming one of the only people to compete using 100% whole foods, optimal exercise nutrition has been on our minds.
Which reminded us how terrible the current options on the market are. You don’t have to wreck your digestion to fuel your workouts.
Let’s expose the top 5 offenders along with a better, natural alternative for each.
1. Energy gels
Endurance athletes swear by them, those tiny, syrupy packets promising a lightning-fast energy boost. But what they don’t tell you? These ultra-concentrated sugar bombs are notorious for causing bloating, stomach cramps, and diarrhoea (a.k.a. the infamous “runner’s trots”).
What they don't tell you
When you’re in the middle of intense exercise, your body redirects blood away from digestion and straight to your muscles. This leaves your gut in a compromised state, under-perfused and vulnerable to irritation. Now, picture a thick syrupy gel, often loaded with maltodextrin, suddenly hitting that fragile digestive system. It ferments way too rapidly, leading to gas, bloating, and emergency sprints to the nearest loo.
Research shows that 30–70% of endurance athletes experience gastrointestinal distress during races, with carbohydrate gels being a major culprit.
Our favourite fuel swap
Instead of syrupy sugar bombs, opt for nature’s most bioavailable energy source: raw honey. It delivers quick digesting glucose without the gut strain, while a pinch of celtic sea salt replenishes lost electrolytes, supporting hydration, nerve function, and muscle contractions. Depending on your climate, you can get creative with your fruit juices, though orange, lime and sea salt is always a classic.
2. Multivitamins
Multivitamins are often seen as an easy way to "cover all bases" nutritionally. However, most commercial multivitamins are made with synthetic, isolated nutrients that lack the natural cofactors needed for proper absorption.
What they don't tell you
The body struggles to process these synthetic forms, leading to poor bioavailability and, in some cases, digestive irritation, nausea, or constipation. Certain common ingredients, such as high-dose vitamin C, magnesium oxide, and synthetic iron, can be particularly harsh on the gut, causing cramps or diarrhoea.
Additionally, many multivitamins contain artificial fillers, binders, and colorants such as titanium dioxide and polyethylene glycol, both of which have been linked to gut bacteria disruption.
Our favourite fuel swap
The answer to this was always going to be organ meat. You can spend hundreds on supplements and still not cover the full spectrum of nutrients a single piece of beef liver, or heart, covers. Bone marrow is another ancestral goldmine packed with fat-soluble vitamins and collagen to heal the gut lining and support optimal absorption. Befriend your local butcher, toss your synthetic multivitamin and eat real nutrients instead.
3. Pre-workout powder
Most pre-workouts are little more than synthetic caffeine bombs laced with gut-disrupting fillers. Their ingredient cocktails can hit your gut as hard as they hit your nervous system, and if you’ve ever chugged one and instantly felt nauseous, jittery, or needed an emergency bathroom run, you’re not alone. And with their neon colours, these guys don't even try to look harmless.
What they don't tell you
Excess caffeine, often 200–300mg per serving or more, triggers a surge in stomach acid production, leading to acid reflux, cramping, and digestive irritation. Artificial sweeteners like sucralose and aspartame further disrupt gut health by altering the microbiome, reducing beneficial bacterial diversity, and increasing inflammation.
Our favourite fuel swap
Another organ. Heart. One of the best natural sources of Coenzyme Q10, essential for cellular energy and endurance. Beetroot juice for nitric oxide production and better blood flow. Sea salt and honey, notice how these repeat? You really don’t need a lot. No stimulants, no artificial fillers, just real, bioavailable fuel.
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4. Whey protein powder
Whey protein was never the answer. Overprocessed, denatured, and often loaded with gut-disrupting fillers, it’s a poor excuse for real nutrition (no wonder it causes you horrible gut reactions).
What they don't tell you
Whey protein, extracted from milk during cheese production, undergoes extensive processing to become the powders commonly seen on store shelves. This processing not only affects its nutritional profile but also introduces potential risks to digestive health and overall well-being.
High-heat processing during filtration and drying stages can denature whey proteins, altering their structure and reducing their biological activity. This denaturation not only affects protein quality but may also impact how well the protein is digested and utilized by the body.
To make matters even worse, to improve taste, texture, and shelf life, manufacturers often add artificial flavours, sweeteners (such as sucralose), stabilisers, and preservatives.
Our favourite fuel swap
The fuel Niall is relying on to prep for his race? It’s the one he created out of frustration, after years of gut issues from conventional protein powders.
It baffles us that we’re the first to make a 100% natural organ blend with protein, collagen, and colostrum, packed with bioavailable nutrients your body actually knows how to use. No isolates, no fillers, no artificial sweeteners, just raw, whole-food ingredients, minimally processed to preserve every last nutrient.
And yet, companies still reach for artificial flavourings when honey, dates, and maple syrup exist, and couldn’t taste more perfect. In all fairness, almost all manufacturers refused to work with us, claiming it was too difficult to keep these ingredients raw. But we weren’t willing to compromise. The enzymes, cofactors, and full nutritional integrity had to stay.
5. Granola bars
To be fair, granola bars have definitely got some bad press recently, and it is rightfully so.
What they don't tell you
Most contain hidden ingredients like seed oils and high-fructose corn syrup that can wreak havoc on your digestive system. Seed oils, such as soybean oil and sunflower oil, are commonly used due to their low cost and long shelf life. However, they are high in omega-6 fatty acids, which, when consumed in excess, can promote inflammation in the gut and throughout the body.
High-fructose corn syrup, a cheap sweetener prevalent in processed foods, poses another threat. It has been linked to increased intestinal permeability, or "leaky gut," which can lead to digestive discomfort, bloating, and even contribute to inflammatory bowel diseases
Our favourite fuel swap
Unlike processed bars, a crunchy, salty piece of jerky is naturally satiating, easy to digest, and free from gut-wrecking additives. Opt for a high-quality, unprocessed jerky, preferably grass-fed, free from seed oils, and cured with simple, ancestral ingredients. Pair it with dried fruit for a natural carb boost, and you’ve got a snack built for true endurance.
