Changes in body odor are often the result of lifestyle changes, such as an altered diet or exercise regimen. However, in some cases, a sudden change in body odor may be a sign of an underlying health condition.

Generally speaking, body odor can affect anyone, and it should not usually cause a person to worry. In most cases, people can prevent it by practicing good hygiene.

Keep reading to learn more about the most common causes of a sudden change in body odor, how to treat it, and when to see a doctor.

a woman out running with a trainer that is causing sudden change in body odorShare on Pinterest
A new exercise regime may cause sudden change in body odor.

Sweat mixed with bacteria is the main cause of body odor, but not all sweat is the same. The reason for this is that people have two different kinds of sweat glands.

Eccrine glands

There are large numbers of eccrine glands on the soles of the feet and the palms of the hands, as well as on the forehead, cheeks, and armpits. The sweat that they produce is watery and does not smell.

Apocrine glands

People have apocrine glands in the armpits and around the genitals. These glands produce a thick, transparent liquid, which can smell quite potent when it mixes with bacteria on the skin.

There are several possible causes of changes to body odor, including:


When someone exercises, their body sweats to help them maintain a steady temperature. When this sweat mixes with bacteria on the skin and then dries, it can smell. People usually refer to this body odor as BO.

Other reasons why someone may sweat more than usual include:

  • having overweight or obesity
  • being in a hot environment
  • stress


Some foods can lead to a change in body odor. The high fiber content of cruciferous vegetables — such as cabbage, cauliflower, and kale — can, for example, add an egg-like smell to the gas that a person passes. Asparagus often leads to smelly urine.

Foods such as garlic, onions, cumin, and curry can also cause changes in body odor. The sulfur-like compounds that the body releases as it breaks down these foods can react with the sweat on the skin, producing body odor that may be different than a person’s natural scent.

Drug side effects

Some medications can cause excessive sweating, which can lead to changes in body odor in some people. Some of the most common examples of these drugs include:

  • desipramine (Norpramin)
  • nortriptyline (Pamelor)
  • pilocarpine (Isopto Carpine)
  • protriptyline (Vivactil)
  • zinc supplements, such as Cold-Eeze, Galzin, Orazinc, or Zincate

The product packaging should list all of the drug’s possible side effects. However, it is important to note that not everyone taking the medication will experience side effects.

Health conditions

In some cases, sudden changes in body odor result from an underlying health condition.


People with hyperhidrosis sweat excessively from the eccrine glands. Eccrine sweat does not tend to lead to body odor, but it can do if it mixes with apocrine sweat.

Plantar hyperhidrosis causes excessive sweating in the feet, leading to smelly feet.

A person may have primary hyperhidrosis, meaning that it happens on its own, or the excessive sweating may be a symptom of another medical condition. It can also be a side effect of some medications.


Trimethylaminuria is a rare genetic condition. People who have it are unable to break down a chemical compound called trimethylamine. The compound leaves the body in the sweat, urine, and breath, giving off a smell resembling that of rotten egg, fish, or garbage.


Body odor may be a sign of diabetes in some people. It happens when there is too much glucose in the blood. Diabetes is a long-term condition, meaning that there is no cure, but people can manage it.

Other symptoms include:

  • needing to urinate more often
  • excessive thirst
  • extreme hunger
  • severe tiredness
  • blurry vision
  • slow healing of wounds

Kidney disease

Sometimes, body odor can be a sign of kidney disease, which means that the kidneys are damaged and unable to filter the blood in the way that they should. Other symptoms include:

  • extreme tiredness
  • difficulty concentrating
  • difficulty sleeping
  • dry, itchy skin
  • needing to urinate more often than usual
  • foamy urine
  • swollen feet

The International Hyperhidrosis Society offer the following advice to people who are worried about excessive sweating and body odor:

  • keep the affected area of skin clean and dry
  • use antiperspirant
  • wash regularly with antibacterial soap
  • use a deodorant to mask the odor

People worried about smelly feet can change their shoes and socks regularly. They can also use powders and antiperspirants to control the moisture.

Anyone who suspects that a sudden change in body odor is due to an underlying health problem should speak to a doctor.

Conditions such as kidney disease and diabetes are serious and require medical attention.

Everyone experiences body odor sometimes, and it is not usually a cause for concern. Likewise, in most cases, people should not be concerned about changes to the odor.

When people sweat, the liquid can mix with bacteria on the skin and lead to a pungent smell. The best way to avoid this is to keep the affected area clean and dry.

Sometimes, a change in odor might be the result of an underlying health problem. Diabetes and kidney disease, for example, can both lead to a change in body odor. Anyone who suspects that they may have such a condition should speak to a doctor as soon as possible.