Sweaty armpits are never exactly fun, but the situation gets even worse if you’re dealing with an unpleasant odour as well.

Smelly armpits typically aren’t cause for concern, says dermatologist Joshua Zeichner, MD, in the article Why Do My Armpits Smell So Bad? A Dermatologist Weighs In.

"We sweat to help maintain our core body temperature,” he explains. "Sweat glands are stimulated by our nerves in response to hot weather, emotional stress, or strenuous activity.”

Sweating is a normal experience for all of us, and a necessary body function. But excess sweating, coupled with a bad smell, might require one to consult a doctor. 

What causes smelly armpits and when should one speak with a doctor?

Serge Ndagijimana, the president of the Association of Medical Students in Rwanda, says, "When people sweat, the liquid mixes with the bacteria on the skin. When this dries, it can cause an unpleasant smell. That is why the armpits regularly present a bad smell.”  

When a person exercises or the weather is too hot, the sweat glands release sweat, which evaporates and cools the body down, he adds.  

Medics suggest that there are two to four million sweat glands in the body. They normally become more active in both males and females during puberty. As a result, it is common for teenagers to have smelly underarms that was not the case before.

However, some people may have a medical disorder that makes them sweat more than they should. People who have the disorder have overactive sweat glands that release sweat even when they are not hot or exercising.

Ndagijimana adds that eating some foods, including garlic and onions, can make sweat smell different. "Alcohol can have this effect and consuming certain foods and drinks may, therefore, lead to a sudden change in body odour around the armpits.”

The science of stink

In an article by Inam Sarah Pangin titled, Underarm Odor Home Remedies: How to get rid of bad armpit smells, she says, sweating or perspiration is a natural process arising out of stress, exercise and high temperatures. This same natural process becomes a nuisance, aka body odour, when perspiration/sweat encounters bacteria on the skin. According to Dr Jamuna Pai, India’s leading skin expert, sweat itself does not smell, but coupled with the dead skin cells, it provides a medium for the bacteria to grow. This bacteria, breaks down the sweat causing unpleasant body odour. 

Treatment

Shema Ruzibiza, a medical student at the University of Rwanda, proposes that good hygiene can help prevent smelly armpits by getting rid of the bacteria that causes the odour.

"It’s just a matter of taking a bath at least once a day and after exercise. We also need to wear clean clothes every day and change clothes after exercising,” he says.

In addition to practicing good hygiene, people can try other ways to avoid smelly underarms. These include; shaving the armpits and applying some antiperspirant deodorant, and following a healthy and balanced diet complete with nutritional supplements. Also, wear pure cotton clothes. 

A diet rich in fruits and vegetables, adequate protein intake, whole grains and supplements like Vitamin B complex and zinc is recommended and of course a minimum of 2-3 litres of water daily.

"Avoiding excessive consumption of garlic and onions may also help,” adds Ruzibiza.  

As sweat collects in the hair follicles leading to bacteria build-up, it is appropriate to restrict the hair growth and keep the area clean.

These simple measures might not work for people with an overwhelming smell, and Ruzibiza suggests the help of a doctor in this case.

"Everyone will have sweaty armpits from time to time. It is perfectly normal and a necessary body function. But if smelly armpits are a more frequent occurrence, though, then it would be wise to consult the doctor,” he says.

In this case, he suggests, the person might be infected with hyperhidrosis, which is an excessive sweating disorder. Most of the time it causes social problems such that one feels uncomfortable in public.

What about antiperspirant and deodorants?

Pangin writes, ‘Use anti-antiperspirant lotions if you sweat excessively. These lotions contain aluminium chloride and should be used in the underarms, palms and soles at night. They work on reducing the amount of sweat. Deodorants do not prevent or control the amount you sweat, but they help to mask the body odour.