Trapped wind is uncomfortable, sometimes genuinely painful, and often hard to trace — gas can build for hours, or even a day, after the meal that started it. In the moment, walking, gentle movement, peppermint tea and lying on your left side all tend to help. If it keeps happening after particular meals, the more useful question is which foods are behind it.

Gassy and uncomfortable after meals? Food could be the link.

Uncomfortable and embarrassing — and weirdly hard to pin down, because gas can build hours, even a day, after the meal that started it. A non-invasive hair screen of 700+ items gives you a shortlist of foods worth trialling first, so a structured elimination replaces the guessing — report emailed within 3 working days of your sample reaching our UK lab, with a 90-day money-back guarantee behind it.

What this screen is — and what it is not

What it is

A way to screen for foods that might be worth removing and reintroducing to see if they affect gas and wind in YOUR body
Based on common patterns in how bodies respond to fermentable foods
A practical elimination approach to help you spot your own personal triggers
One piece of information — alongside how you feel, your GP, and your own experience
Non-invasive (a simple hair sample)
Your report emailed within 3 working days of your sample reaching our UK lab

What it is not

NOT a validated method. There is no robust published evidence that screening hair identifies which foods do or do not suit you — the report is a starting shortlist, and it is the elimination diary that shows a link.
Not a measurement of gas, fermentation, FODMAP handling, enzyme levels, or how you digest lactose — the hair screen does NOT detect any of these
Not a way to name a gut or bowel condition, a food allergy, or lactose handling
Not an IgE allergy test (we don’t test for true allergies)
Not a coeliac screen
Not a way to make gas go away on its own — any change comes from adjusting what you eat, not from the screen
Not evidence that you have a food intolerance — only your own elimination-and-reintroduction experience can suggest that
Not a replacement for seeing your GP if symptoms persist or are severe

Why certain foods create gas

Gas tends to build up when bacteria in your large intestine ferment food that hasn’t been fully broken down earlier in your gut. This often happens because your body either doesn’t make much of the enzyme needed to break a particular food down, or because a food moves through your system quickly. Sugars like lactose (in dairy), fructose (in some fruits), and complex carbohydrates like raffinose (in beans) are common culprits. When these reach your colon still intact, your gut bacteria ferment them, producing hydrogen, carbon dioxide, and sometimes methane — which is the gas you feel. High-FODMAP foods (Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols) are especially prone to this because they aren’t easily absorbed higher up. The bigger the meal, or the faster it moves through, the more the bacteria have to work with, and the more gas is produced. This isn’t a sign that something is ‘wrong’ with you — it’s simply a mismatch between what you’re eating and what your particular digestive system handles comfortably. One important thing to be clear about: the IntoleranceLab hair screen does NOT measure any of this. It can’t see how much gas you make, how you ferment foods, your enzyme or lactose handling, or what’s happening in your gut. It’s a starting point that flags foods worth trialling — the only way to learn whether a food actually bothers you is to take it out and bring it back, and notice how you feel.

Does this sound like you?

Gas or flatulence within 1–3 hours of eating
Bloated or distended belly, especially in the afternoon or evening
Feeling of trapped wind or pressure in the abdomen
Stomach gurgling or audible rumbling
Needing to loosen clothing after meals
Bloating easing after passing wind or going to the toilet
Smelly or less smelly gas depending on what you’ve eaten
Symptoms that worsen after high-fibre or legume-based meals

Related foods worth checking at the same time

Lactose-containing dairy, if lactose is a trigger for you (milk, cheese, ice cream may worsen symptoms)
Gluten-containing grains, if wheat-based foods seem to bother you (wheat, barley, rye)
Processed foods with polyols and sugar alcohols (sorbitol, xylitol, maltitol)
Cruciferous vegetables in large amounts (broccoli, cabbage, Brussels sprouts, cauliflower)
Stone fruits and high-fructose fruits (apples, pears, stone fruits, dried fruit)
Beans, lentils, and legumes in concentrated amounts

Foods and items commonly linked to gas & wind

These are the kinds of items people most often look at for this topic. For the definitive list of what each screen covers, see the full food list and the non-food list.

Beans (kidney, black, pinto)
Lentils
Chickpeas
Onion
Garlic
Broccoli
Cauliflower
Cabbage
Wheat
Apple
Pear
Milk (lactose)
Sorbitol & other polyols
Honey (high-fructose)

How to run a focused elimination

Plan for The 6-week core plan: a structured elimination with a food diary, then a careful reintroduction one food at a time afterwards.

Day one: start your food diary — what you ate, when, and when gas or bloating showed up. It’s how you’ll spot patterns, and the 90-day money-back guarantee asks you to follow your plan for at least 6 weeks with a food diary, so it counts twice.
Weeks 1–2: remove your shortlisted foods completely — for gas that’s often beans, lentils, onions, cruciferous vegetables or wheat. Keep meals simple and keep everything else the same.
Weeks 3–4: keep them out. Many people notice wind easing somewhere in the second week; others take longer. Note what changes and what doesn’t.
Weeks 5–6: hold steady so your diary shows a clear before-and-after. If nothing has shifted by the end of week six, the foods you removed probably aren’t your triggers — which is also a real answer.
Afterwards — reintroduce one food every 3–4 days in normal portions, recording what you eat and how your body responds (bloating, gas timing, how it feels). If gas returns, you’ve likely found a culprit; if not, that food goes back on the menu.
Build your personal baseline: by the end you’ll know which foods sit well with you, which to limit, and which to keep for occasional treats.

Reintroduce one food at a time, every 3–4 days, in a normal serving, and watch for symptoms to reappear. If gas or bloating comes back, that food may be a trigger for you; if you feel fine, it’s probably one you tolerate well. Some people find they can manage small amounts of a food but not large ones — portion size matters. Keep your food and symptom diary going throughout. Remember, it’s this hands-on process of removing and reintroducing that tells you the most, not any test result on its own.

Common questions

Is wind and gas the same thing?

Wind (or trapped air) and gas (produced by fermentation) are related but slightly different. Trapped wind is air you’ve swallowed or air that’s been produced but isn’t moving through your system. Gas is the hydrogen, carbon dioxide, and methane produced when bacteria ferment undigested food. Both can cause bloating and discomfort, and they often happen together. An elimination diet — taking foods out and bringing them back — helps you spot which foods either create more gas or slow your digestion down (which traps gas).

Why do beans always give me gas?

Beans contain complex sugars called oligosaccharides (raffinose and stachyose) that your body can’t easily break down. They pass into your colon intact, where bacteria ferment them and produce gas. This is simply the chemistry of beans rather than a sign of anything unusual about you. Soaking beans overnight and discarding the water, cooking them well, and eating smaller portions can sometimes help. But if beans consistently bother you, they’re a good candidate for your elimination list, so you can take them out for a while and see whether it makes a difference.

Can I have wind even if dairy doesn’t bother me?

Absolutely. Gas and bloating have many possible causes beyond lactose. FODMAPs (fermentable carbohydrates), wheat, beans, cruciferous vegetables, and even fibre eaten too quickly can all bring on wind. Lactose is just one possible trigger. Working through an elimination diet helps you identify YOUR specific triggers, whatever they turn out to be.

Why does the timing of symptoms matter?

Fermentation and gas don’t happen instantly. Depending on what you eat, how much you eat, and how quickly you digest, gas may appear 1–3 hours after a meal, or even 12–48 hours later. This delay makes patterns tricky to spot without a food diary — and it’s why so many people blame the wrong meal entirely. By writing down what you ate and when symptoms appeared, you can connect the dots and zero in on your real triggers rather than guessing.

Is smelly wind worse than non-smelly wind?

They’re just different. Non-smelly wind is mostly hydrogen and carbon dioxide; smelly wind contains more sulfur compounds, often from fermenting certain amino acids in protein-rich foods. Smelly wind isn’t ‘worse’ — it’s just information. Some people notice theirs smells stronger after red meat, eggs, or vegetables like cruciferous greens. Tracking this detail can help pinpoint your triggers too.

Is an intolerance the same as an allergy?

No — they’re different kinds of reaction. An allergic reaction involves your immune system and tends to happen quickly: hives, swelling, difficulty breathing. What people usually mean by a food intolerance or sensitivity is a digestive reaction — a food is hard for you to break down, it ferments, and you get gas, bloating, or other tummy symptoms. The IntoleranceLab screen checks your sample across 700+ items to give you a shortlist for an elimination trial; it isn’t an IgE allergy test, and a true allergy is something to discuss with your GP.

Should I see my GP before doing an elimination diet?

If your gas and wind are mild and occasional, an elimination diet is a safe, straightforward way to explore triggers. If your symptoms are severe, persistent, or come with pain, diarrhoea, or weight loss, or if they’re affecting your quality of life, speak to your GP first. They can look into other causes and may refer you to a dietitian. An elimination diet is a helpful self-care tool, but it isn’t a replacement for professional medical advice if something feels seriously wrong.

How long until I notice a difference?

Many people notice bloating and gas easing within 5–10 days of removing trigger foods, though some take up to 2–3 weeks to feel the full effect. Once you stop fermenting the food that was bothering you, symptoms often settle. If you don’t notice any change by the end of your 6-week plan, the foods you cut out probably aren’t your triggers — so you can bring them back and explore other suspects. Any improvement comes from changing what you eat, not from taking a test.

Can I have wind even if I eat slowly and chew well?

Yes. Eating slowly and chewing thoroughly helps your digestion, but it won’t stop gas if you’re eating foods your body struggles with (like high-FODMAP foods or, for some, lactose-containing dairy or wheat). Good chewing helps, but the chemistry of fermentation is the real driver. If a food ferments in your colon, it will produce gas whatever your technique.

Is it normal to have wind?

Yes — some wind is completely normal and a natural part of digestion for everyone. It only becomes a problem when there’s too much, or when it’s uncomfortable or affecting daily life. If wind is leaving you bloated, self-conscious, or uncomfortable for hours after eating, it’s worth exploring your triggers. Your GP can also help if you’re concerned.

When to speak to your GP. If wind and gas are persistent, severe, or come with abdominal pain, diarrhoea, constipation, unexplained weight loss, or blood in your stool, please see your GP. These can sometimes point to other causes that are worth checking. An elimination diet is a useful self-care tool, but it isn’t a substitute for professional medical advice if something feels seriously wrong.