5 dietary tips to fix your bloating
Your jeans called. They want their waistline back.
Bloating.
The single most common complaint I hear in clinic.
Every. Single. Week.
“I look six months pregnant by 3pm.” “I have to undo my trousers after lunch.” “It’s worse in the evening….I just feel enormous.”
I hear you.
So let’s say you’ve had all the tests. Bloods. Stool samples. Maybe even a camera. Maybe even a scan! Everything came back normal. And you’re still bloated.
Good news: nothing sinister is going on.
Better news: some remarkably simple dietary changes can make a real difference.
You can check out my full Substack here
Important disclaimer: Persistent bloating, especially if it’s new, worsening, or accompanied by weight loss, bleeding, or a change in bowel habit needs a specialist opinion first. These tips assume your doctor is happy there is no sinister cause. I wrote about red flag gut signs here.
Read this bloating guide first here
1. Unblock the plumbing first
Constipation is the most common cause of bloating.
By FAR!!!
Not food intolerances. Not SIBO (Small Intestinal Bacterial Overgrowth)
Constipation. The NUMBER ONE cause for bloating.
When stool sits in the colon too long, bacteria ferment it, producing hydrogen, methane, and carbon dioxide.
That gas has nowhere to go. The result? A balloon behind your belly button.
The fix? Get things moving. Some foods potentially do this better than medication.
Kiwis. Two a day. A 2023 multicentre RCT (184 patients, three countries) found kiwifruit increased complete spontaneous bowel movements by almost two per week, outperforming psyllium.
Prunes. An RCT comparing 50g prunes twice daily against psyllium found prunes were more effective. They contain sorbitol (a natural osmotic laxative), polyphenols, and fibre. A dried fruit beating a pharmaceutical-grade fibre. I love that.
Figs. A double-blind placebo-controlled RCT found fig paste reduced colon transit time and improved stool consistency over eight weeks.
Pick one. Make it daily. I wrote a deeper dive on constipation foods here.
2. Re-think what you’re drinking
We obsess over food. We rarely think about drinks.
Carbonated drinks pump CO₂ directly into your stomach. MRI studies show 300ml of fizzy liquid significantly increases gastric volume versus still water.
Packaged fruit juices are loaded with fructose. At high doses, up to 80% of healthy people malabsorb it; with around half reporting bloating and diarrhoea.
Energy drinks deliver a triple hit: carbonation, caffeine, and sugar alcohols. A bloating cocktail in a can. AVOID in my opinion.
Milk - if you’re lactose intolerant, this will be an obvious trigger (I’m sure you already know first hand). More on this in Tip 5.
What to drink instead?
Ginger tea - An RCT found 1,200mg of ginger halved gastric emptying time and increased stomach contractions.
Fennel tea - a 2025 study in Neurogastroenterology & Motility confirmed fennel relaxes the upper stomach while promoting contractions in the lower stomach.
Or just plain water. This should be your preferred drink 95% of the time.
3. Fibre is great….but can be bloating
“Eat more fibre” is standard advice. It’s also incomplete.
Soluble fibre (psyllium husk) dissolves in water and forms a gel. It holds moisture, softens stool, and produces minimal gas. A meta-analysis of 14 RCTs found it improved IBS symptoms with a number needed to treat of 7. An MRI study showed psyllium reduced colonic gas production by over 80%.
Insoluble fibre (wheat bran) doesn’t dissolve. It adds bulk but rapidly ferments and can irritate. A landmark 275-patient RCT in the BMJ compared psyllium, bran, and placebo. Psyllium won. Bran had a 44% dropout rate, mostly because symptoms got worse.
If fibre makes you more bloated, you’re eating the wrong kind.
Read my complete fibre guide here
Psyllium husk. Start at 3-4g daily. Build to 10g over two weeks. Always with a large glass of water. Let your gut adapt.
Quick note: raffinose - a sugar in beans, lentils, and cruciferous vegetables - is a common gas trigger. Humans lack the enzyme to break it down, so colonic bacteria do it for us. Don’t avoid these foods. Just introduce them gradually.
4. Nature’s antispasmodic
Peppermint oil blocks calcium channels in gut smooth muscle; a similar mechanism to pharmaceutical antispasmodics. Muscle relaxes. Spasm settles. Gas passes.
A meta-analysis of 12 RCTs (835 patients) found peppermint oil improved IBS symptoms with a number needed to treat of just 3. (Super impressive)
A 2016 RCT showed a 40% reduction in total symptom scores, with bloating specifically improving at 24 hours and four weeks.
Dosage: 180-225mg enteric-coated peppermint oil, two to three times daily, before meals. Enteric coating is essential….without it, you’ll get heartburn.
Fennel seeds - I already touched on this but it needs a double mention. An RCT combining fennel oil with curcumin showed a 50% reduction in IBS symptom severity versus 26% for placebo. The evidence isn’t as isolated as peppermint, but the pharmacology is genuine. Chew them after meals or brew as tea. Simple. Safe. Centuries old.
5. The dairy question
Around 65-70% of the world’s adult population has some degree of lactose malabsorption. Over 90% in East Asian populations. As low as 2-5% in Scandinavians.
The mechanism: lactase (the enzyme that digests lactose) declines after weaning in most humans. Without it, undigested lactose reaches the colon, where bacteria ferment it into gas. Bloating. Cramping. Sometimes diarrhoea.
How to find out: The hydrogen breath test is an option - sensitivity around 75%. You drink lactose, breathe into a machine, and a rise of 20ppm or more confirms malabsorption. Genetic testing for the LCT-13910 polymorphism is also available - definitive for primary deficiency.
Or simply eliminate dairy for 2-4 weeks and see what happens (definitely the most practical method)
Most people with malabsorption tolerate small amounts, especially fermented dairy like yoghurt and aged cheese, where bacteria have already done the digestion.
Lactase enzyme supplements (taken before dairy) can help. A crossover RCT showed a 55% reduction in hydrogen excretion. They’re not magic (effectiveness varies by product and dose) but for the occasional pizza, they’re worth trying.
One more thing….
Watch sugar-free products. Sugar alcohols, sorbitol, xylitol, mannitol, lurk in sugar-free gum, protein bars, and “diet” sweets. They’re poorly absorbed and rapidly fermented. One study found just 10g of sorbitol caused significant bloating; 20g caused severe cramps. If you’re chewing sugar-free gum daily, this could be your invisible culprit.
Wrapping up
Five tips. All evidence-based and pretty simple to follow.
Fix your constipation first. Rethink your drinks. Choose soluble fibre over insoluble. Try peppermint oil and fennel seeds. And consider whether dairy, or hidden sugar alcohols, might be working against you.
Start with one. Audit any differences. Then move to another.
For those wanting to go further, I wrote about the Low FODMAP diet, SIBO and treating IBS without medication all worth a read if bloating is part of a bigger picture.
If you enjoyed this article check out my Substack here
Struggling with liver or digestive issues that affect your daily life? Invest in your gut health with a private, personalised consultation where I will explore your specific symptoms and develop a targeted treatment plan. Take the first step toward digestive wellness today: https://bucksgastroenterology.co.uk/book-an-appointment/ (I offer both in person and video consultations!)
References
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General Disclaimer
Please note that the opinions expressed here are those of Dr Hussenbux and do not necessarily reflect the positions of Buckinghamshire Healthcare NHS Trust. The advice is intended as general and should not be interpreted as personal clinical advice. If you have problems, please tell your healthcare professional, who will be able to help you. Thank you to the amazing photographers from Unsplash where I get most of my images from.
Thanks! I forwarded to a family member who suffers with bloating.
Great stuff! 🙌🙏