Why do some people have bad body odor and others don't?

Some people have virtually no body odor, even without using deodorant. On the other hand, many others have a very strong body odor. What makes the difference?

Many people start using deodorant during puberty, when hormonal changes increase sweat production - Photo: Physicians Rejuvenation Center

In August, content creator Alexis DiMaya made a bold claim in a TikTok post. "I never wear deodorant, and I don't stink," she told her more than 500,000 followers.

Why do we have body odor?

Many people start using deodorant during puberty, when hormonal changes increase sweat production. We rely on this product to not only control sweat, but also keep our bodies odor-free.

Contrary to popular belief, sweat itself does not have an odor. Sweat is mostly water, along with small amounts of other substances such as sodium and chloride. However, the type of gland that secretes sweat affects how much we smell.

There are two main types of sweat glands involved in this process: eccrine and apocrine. Eccrine glands produce a liquid, odorless sweat to cool the body—the kind of sweat you experience when you're outside in the heat. This sweat evaporates from the skin.

Next are the apocrine glands, which are more likely to produce odor, says dermatologist Dr. Connie Yang of PFRANKMD Dermatology Center in New York City. "Apocrine glands are located in hairy areas like the armpits, pubic area, and scalp, and secrete thicker sweat," she says.

Like eccrine sweat, this sweat doesn't smell right away after it's secreted. But when it comes into contact with bacteria on the skin, the proteins and fatty acids are broken down, "resulting in the body odor we're familiar with," Yang explains.

When we're stressed or anxious, we sweat through our apocrine glands, Yang says. This means we can smell more during times of high stress than when we're sweating on a sunny day at the beach.

Additionally, certain medical conditions can also cause body odor. Trimethylaminuria, a metabolic disorder, produces a fishy odor in sweat, breath, and urine. Kidney problems, diabetes, and even liver failure can all cause your body to produce a stronger odor.

Why don't some people smell bad?

There are a few reasons why some people don’t have much body odor. Dermatologist Dr. Hannah Kopelman says a gene variant common in East Asians affects the production of a protein called ABCC11.

“This gene variant makes some populations less likely to have body odor, because their sweat contains fewer proteins that bacteria can break down into odorous compounds,” says Kopelman.

While this variant is present in 80%-95% of East Asians, according to NBC News, it is only present in up to 3% of Europeans and Africans, according to a 2010 study.

Interestingly, another study also found that most people carrying the ABCC11 gene variant still choose to use deodorant.

In addition to genetics, what you eat can also affect your body odor. Certain foods can make you smell worse, including red meat, garlic, onions, cruciferous vegetables, and alcohol. So if you avoid these foods, you may smell better than someone who eats them regularly. Additionally, spices like curry, cumin, and walnuts can linger in the body, creating a strong odor.

Another factor involved in body odor is emotional. “Stress sweat is very real and likely to smell worse than regular sweat,” says dermatologist Dr. Annabelle Garcia.

This is because your apocrine glands produce more sweat when you are stressed. Finding ways to stay calm in emotionally charged situations, such as through meditation, can help reduce your body odor.

Do I ever not realize I smell?

Yes, according to Kopelman. "People can become 'smell-blind' to their own body odor," she explains. "This happens because the brain tends to filter out constant stimuli, like our own smell, over time, allowing us to focus on new smells in the environment. As a result, we may think we don't smell bad, when in fact others around us can still smell it."

Luckily, there are many ways to combat odor, such as drinking plenty of water to help dilute sweat, avoiding foods that can cause odor, like garlic and onions, and using deodorant or antiperspirant, which helps prevent sweat in the first place.

You can also try using a cleanser containing benzoyl peroxide under your arms, which can help reduce underarm odor.

Also, avoid anxiety-provoking situations and find ways to calm your nervous system so you're less stressed and sweat less.

Source: https://tuoitre.vn/tai-sao-nhieu-nguoi-co-mui-co-the-hoi-nhieu-nguoi-khac-lai-khong-20241030181428099.htm