Dialling up the chilli factor in a challenge to eat the spiciest food can lead to regret in the days after.

Food can take a couple of days to make its way down the gut — and with very chilli-hot food, there is a good chance of getting stomach pain, emitting embarrassingly loud or foul-smelling gas, and suffering burning diarrhoea.

“Food takes a while to go down, and our gut is a really long tube. For food to travel from the mouth to the other end can sometimes take two to three days. The food that isn’t absorbed well gets fermented by the bacteria in the gut, and that will produce quite a lot of gas,” said Associate ProfessorAndrew Ong, Senior Consultant, Departmentof Gastroenterology and Hepatology,Singapore General Hospital (SGH). “What you ate the day before is what’s likely to be inside your gut when you start farting. And today’s poop? It’s from the food that you ate two to three days ago.”

Being able to control the ring-shaped sphincter muscles around the anus might help soften the sound that flatulence typically causes, but it is more difficult to control the smell. “Most of the smell comes from substances like hydrogen sulphide, which comes from proteins. After a buffet or Korean barbecue the night before, with a lot of meat, the toilet can smell like a war-zone the next day,” added Assoc Prof Ong.

This does not mean that vegetarians get a pass from flatulence, although eating less meat protein and more rice, grains and vegetables can help. “Without a lot of protein, I think that would be okay. Even rice and carbohydrates are fine,” Assoc Prof Ong said.

Then there are foods classed as FODMAP — fermentable oligosaccharides, disaccharides, monosaccharides and polyols — which people with irritable bowel syndrome (IBS) should be aware of. High FODMAP foods that aggravate the gut include dairy- and wheat-based products, beans and lentils, and some fruits and vegetables. It is unclear why certain foods cause problems for some people. For them, FODMAP foods just do not get fully absorbed by the body. Instead, food stays in the gut, where it is fermented by bacteria in the gut and produces a lot of gas.

Flatulence and diarrhoea aside, eating very spicy food can cause a burning sensation from the mouth to the stomach and the anus. “It’s dependent also on the quantity of spicy stuff, which we call capsaicin, in the chilli,” said Assoc Prof Ong. When chilli — and the capsaicin — comes into contact with tissue, it causes a burning sensation. The greater amount of capsaicin a chilli has, the hotter and stronger the burning sensation. “So young people who think it is fun to challenge each other to see who can eat the most chilli may want to think first about capsaicin and what it can do to the body!” said Assoc Prof Ong.

Although the body can build a certain tolerance to capsaicin, there is a limit. Assoc Prof Ong noted that in places where chilli is part of the everyday diet, people are able to eat chilli neat. “Go into the kitchen of a curry place, and you can see the cooks wearing gas masks — the chilli burns their eyes and nostrils.”

Another misunderstood food group is milk and dairy products, and why many Asians tend to be lactose-intolerant. “Many Asians don’t have the gene to produce the lactase enzyme. Babies have it when taking breast milk, but as they are weaned to eat a solid diet, they lose that enzyme. So, in theory, Asians shouldn’t be absorbing lactose very efficiently compared to someone in the Caucasian population,” said Assoc Prof Ong.

Intolerance is not the same as an allergy. A person will not be able to consume a particular food he is allergic to without dire consequences. With an intolerance, the person can slowly build a tolerance to it. For instance, consuming small amounts of milk, nuts or shellfish — common food groups that people have an intolerance to — may not lead to an upset stomach.

Probiotics and other gut supplements may help some, but Assoc Prof Ong believes that a moderate diet and a healthy lifestyle that includes exercise and seven to eight hours of sleep make a greater difference to gut health. “Eat a balanced diet, with nothing in excess. Sleep well to lower the sensitivity of your gut. Exercise leads to good gut health as it produces movement of your blood and reduces the sensitivity of your nerves,” he said.

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