By Kirstie Vesseur, Registered Clinical Nutritionist (CNA), Legacy Nutrition, NZ and Australia.
You eat lunch and by mid-afternoon your waistband is digging in. By dinner you look a few months pregnant and you are quietly undoing the top button. You have already cut out gluten, dairy and onion, and you are running out of foods you feel safe eating.
If you are always bloated, I want you to know two things. It is very common, and it is not something you just have to put up with. In clinic I see this pattern often, and it is rarely solved by removing yet another food. It usually improves once we understand why your gut is reacting the way it is.
Why am I always bloated? The common drivers
Bloating is a symptom, not a diagnosis. These are the drivers I look at first.
Bacterial overgrowth in the small intestine (SIBO)
Most of your gut bacteria are meant to live in the large intestine. With SIBO, more bacteria than usual sit higher up, in the small intestine, where they can ferment carbohydrates and produce gas soon after you eat. SIBO bloating often builds as the day goes on and may come with burping, wind, cramping, and loose stools, constipation or a mix of both.
Low stomach acid
Stomach acid starts protein digestion and helps keep bacterial numbers in check in the upper gut. Acid production can be lower with H. pylori infection, some autoimmune conditions, ageing and long-term use of reflux medicines (proton pump inhibitors), which are also linked with a higher risk of SIBO. If you are on reflux medication, please do not stop it. Talk to your GP about whether it is still the right fit for you, and ask about H. pylori testing if you have upper tummy pain, burping or indigestion.
An unbalanced gut microbiome
Your gut bacteria are a large, mixed community. Antibiotics, a low-fibre diet, chronic stress and poor sleep can all shift this balance, which may change how much gas the same meal produces.
Hormones and gut movement
Oestrogen and progesterone both affect how your gut moves and how sensitive it is. Many women notice more bloating and changes in bowel habit in the days before and during their period, and symptoms often shift again in perimenopause. If your bloating follows a monthly pattern, the cause may be cyclical rather than a new food reaction. My article on the gut-hormone connection explains this further.
Food intolerances and digestive shortfalls
If some carbohydrates are not fully absorbed higher up, more of them reach the large intestine for bacteria to ferment. Lactose intolerance is the classic example. Pale, floating or greasy stools can be a sign that fat is not being absorbed well, and are worth raising with your GP.
What standard testing can miss, and what to check
IBS is the label many women with ongoing bloating are given. It is a real and useful diagnosis, made once other conditions are ruled out, but it describes the symptoms rather than explaining why they are happening.
First, please see your GP to rule out coeliac disease, inflammatory bowel disease and other medical causes. Useful tests to discuss include:
- Coeliac blood test (tTG-IgA with total IgA), done while you are still eating gluten. If you have already cut gluten out, ask your GP about eating it again before testing (usually daily for about 6 weeks). A full blood count and iron studies are worth doing at the same time.
- Faecal calprotectin, a stool test that helps tell IBS apart from inflammatory bowel disease.
- H. pylori testing if you have upper tummy symptoms.
- SIBO breath test. This is usually done privately in New Zealand and Australia. After an overnight fast and a low-fibre diet the day before, you drink a sugar solution (glucose or lactulose) and give breath samples every 15 to 20 minutes for 2 to 3 hours, measuring hydrogen and methane. Avoid antibiotics for about 4 weeks beforehand. Results need to be read alongside your symptoms.
When to see your GP promptly
Please do not wait if bloating is new and persistent (most days for 3 weeks or more), especially over 40, or if it comes with feeling full quickly, needing to pass urine more often, pelvic or tummy pain, unexplained weight loss, iron-deficiency anaemia, blood in your stool, bloating that wakes you at night, vomiting, an ongoing change in bowel habit, or a family history of bowel or ovarian cancer.
What may help your gut
The right plan depends on what is driving your bloating, so this is a starting point rather than a protocol.
Food foundations
- A short-term low FODMAP approach. Of the diets studied for IBS, low FODMAP has the strongest evidence for reducing bloating and overall symptoms. It is designed to be temporary: a strict phase of 2 to 6 weeks, then foods are reintroduced one group at a time, ideally with guidance, so your diet does not keep shrinking.
- Two green kiwifruit a day (if you are not allergic to kiwifruit). In an international trial run partly in New Zealand, eating 2 green kiwifruit daily for 4 weeks improved bowel frequency and abdominal comfort in people with constipation.
- Fibre, increased slowly. If you bloat easily, add fibre gradually, for example starting with 1 teaspoon of psyllium husk or 1 tablespoon of ground flaxseed a day with a large glass of water, and building up over 2 to 3 weeks. Take fibre supplements at least 2 hours apart from medicines such as thyroxine, as fibre can reduce their absorption.
- Protein you can digest. A palm-sized serve of protein (roughly 20 to 30 g) at each meal, cooked simply, is often better tolerated than large, heavy portions.
- Regular meals. Three meals a day, without grazing constantly, may give your gut time between meals for its natural "clean-up" waves of movement.
Supplements with some evidence
- Enteric-coated peppermint oil capsules: a meta-analysis of 10 trials found peppermint oil improved overall IBS symptoms and tummy pain compared with placebo, although the evidence is very low quality and side effects such as heartburn were more common. Typical adult doses in trials are 180 to 225 mg (about 0.2 mL) of peppermint oil, taken 2 to 3 times a day before meals. Swallow capsules whole, and do not take them at the same time as antacids or acid-reducing medicines, which can dissolve the coating early. Avoid it if reflux is a problem for you, and check with your GP first if you have gallbladder or liver disease. It is not for children unless a health professional advises it.
Other options I sometimes use, with more limited evidence, include digestive enzymes, specific probiotic strains, glutamine or zinc carnosine. The right product and dose depends on your results, and more is not better here: some people find certain probiotics make their bloating worse.
Check with your GP or pharmacist before starting any supplement if you take medication or are pregnant or breastfeeding.
Stress, eating habits and movement
Your gut has its own nervous system, and it is closely connected to your brain. Stress can change how your gut moves and make it more sensitive, which is why bloating often flares in stressful weeks.
Small changes help more than most people expect:
- Sit down to eat, and put your phone away.
- Eat slowly and chew each mouthful well.
- Take three slow breaths before your first bite.
- Go for a 10 to 15 minute walk after your main meal. Gentle movement may help gas move through rather than build up.
If stress is a big part of your picture, my free 7-Day Nervous System Reset is a good place to start.
Frequently asked questions
Can hormones cause bloating?
Yes. Many women notice more bloating around their period and in perimenopause. If your bloating follows a monthly pattern, track it alongside your cycle for 2 or 3 months.
Should I cut out more foods?
Usually not without a plan. Long-term restriction can reduce the variety of your gut bacteria and make it harder to get enough fibre and nutrients. A short, structured trial with a clear reintroduction phase is more useful than ongoing elimination.
How is SIBO tested?
With a breath test. You drink a sugar solution and give breath samples every 15 to 20 minutes for 2 to 3 hours. A rise in hydrogen, or a raised methane level, suggests bacterial overgrowth, and results are read alongside your symptoms.
Where to start
If you are always bloated and elimination diets have only helped a little, it is worth looking at the cause rather than the next food to cut. My free guide, The Gut-Hormone Connection, is a helpful first read.
Want help with this one-on-one? See how I work with women on gut health and bloating, or browse all my services.
This article is general education, not personal medical advice. Please talk with your GP before starting supplements or changing medication.
References
- Black CJ et al. Efficacy of a low FODMAP diet in irritable bowel syndrome: systematic review and network meta-analysis. Gut, 2022. Link
- Ingrosso MR et al. Systematic review and meta-analysis: efficacy of peppermint oil in irritable bowel syndrome. Alimentary Pharmacology and Therapeutics, 2022. Link
- Gearry R et al. Consumption of 2 green kiwifruits daily improves constipation and abdominal comfort: an international multicenter randomized controlled trial. American Journal of Gastroenterology, 2023. Link
- Rezaie A et al. Hydrogen and methane-based breath testing in gastrointestinal disorders: the North American consensus. American Journal of Gastroenterology, 2017. Link
- Mulak A, Taché Y, Larauche M. Sex hormones in the modulation of irritable bowel syndrome. World Journal of Gastroenterology, 2014. Link
