Bloating and heaviness after eating
A stomach that grows through the day and is two sizes bigger in the evening than it was in the morning is almost always gas, not fat. The question is where the gas comes from.
If your stomach is flat in the morning and tight and uncomfortable by evening, that is not weight gain. Fat does not accumulate and disappear within twelve hours. That is volume entering or being produced inside during the day. In nearly all cases it is gas, sometimes retained water.
Where the gas comes from
Bacteria in the large intestine ferment carbohydrates that the small intestine failed to absorb. Fermentation produces gas. This is a normal process and everyone has it. It becomes a problem when the volume exceeds what the body can move along comfortably.
Three things increase it: more unabsorbed carbohydrate reaching the large intestine, bacteria having moved higher up than they should be, or the gut wall reacting more sensitively to a normal amount of gas.
The most common specific causes
Lactose intolerance
Around sixty to seventy percent of adults worldwide lose much of the enzyme lactase after childhood. This is not a disease, it is the norm for the species. The pattern is characteristic: bloating, rumbling and often loose stools, starting between thirty minutes and two hours after milk, ice cream or a large amount of fresh cheese.
Yoghurt and hard aged cheeses are usually tolerated, because the lactose in them has already been broken down.
Wheat and fructan sensitivity
There is an important distinction here. Coeliac disease is autoimmune and is confirmed by blood test and endoscopy. It requires complete lifelong gluten avoidance and must be diagnosed by a doctor before you stop eating bread, because the test comes back falsely negative if you are already gluten free.
Separately from coeliac disease there is intolerance to fructans, found in wheat, onion, garlic and legumes. Many people who believe they react to gluten are in fact reacting to fructans.
Eating too fast
The most underrated cause. When you eat quickly you swallow air along with the food. Fizzy drinks, chewing gum and drinking through a straw do the same. The effect is immediate and entirely reversible.
Constipation that does not feel like constipation
Days do not have to pass without a bowel movement. If emptying is incomplete, the abdomen stays full and the gas has nowhere to go.
Irritable bowel syndrome
A diagnosis made by a doctor after other things have been ruled out. Typically the pain eases after a bowel movement, and the bloating varies a great deal from day to day.
When bloating is not harmless
See a doctor promptly if you have
- Bloating that does not come and go but stays and worsens
- Weight loss you were not trying for
- Blood in the stool, or black stools
- Pain that wakes you at night
- Vomiting that will not stop
- Difficulty swallowing
- Bloating that starts for the first time after the age of fifty
- Family history of bowel or ovarian cancer
How to find your cause
The most useful thing you can do costs nothing. Two weeks of a diary.
Write down what you eat, at what time, and how you feel two and four hours later on a scale of one to ten. Most people spot the pattern themselves by the end of the second week. The repeats are clearer than you expect.
If the diary shows nothing, the next step is a structured exclusion of one food group for two or three weeks and then bringing it back. One at a time, not everything at once, because otherwise you learn nothing.
What helps straight away
- Eat more slowly. Put the fork down between bites. Sounds trivial, works.
- Smaller portions, more often. A large meal overloads the system in one go.
- Walk after eating. Ten minutes speeds up stomach emptying.
- Less fizzy drink and chewing gum. That is imported air, pure and simple.
- Watch the sweeteners. Sorbitol, maltitol and xylitol in sugar-free gum and sweets are notorious for bloating.
- More water if you increase fibre. Fibre without water makes things worse.
About intolerance tests
You will come across plenty of advertising for tests that promise a list of foods to avoid. It is worth knowing what sits behind them. The IgG antibody blood tests most commonly sold show exposure to a food, not intolerance to it. It is normal to have IgG to the things you eat regularly.
The only thing that genuinely proves a link between a food and a symptom is removing it and reintroducing it in you specifically. Any test that points in a direction is a starting point for that experiment, not a substitute for it.
Want to narrow it down?
Sometimes it is easier with someone outside it to order the sequence of trials. Call us and we will tell you honestly whether it is worth it.
Book a sessionNLS, Vega and EAV are wellness methods for orientation, not medical diagnostics. This article is educational and is not medical advice. It does not replace examination, testing or consultation with a doctor. Do not stop or change prescribed treatment without your doctor.