Why Do Some People Sweat More Than Others?

POPSUGAR Photography | Matthew Kelly
POPSUGAR Photography | Matthew Kelly

Sweat is amazing. It may seem embarrassing or frustrating — especially in social situations like a job interview or first date — but sweat is one of the most important ways your body takes care of you.

"Sweating actually assists with your body's thermal regulation, skin hydration, and helps balance our fluids and electrolytes," nurse practitioner Melissa Holtz, CNP, tells Cleveland Clinic. This means that sweat is your body's natural cooling mechanism.

During physical activity, hot weather, or even stress, your body must maintain homeostasis — or balance — and prevent you from getting too hot or too cold. Think about how you shiver when it's cold outside as your muscles contract and relax to keep in the heat. Sweating does the opposite to allow you to cool down. Both are natural attempts by your body to maintain homeostasis.

Some people tend to sweat more than others (we'll get into that later), but it's important to know the basics of what sweat actually is, how it happens, and what to do if you think your sweating may be problematic.

What Is Sweat?

A drop of sweat is about "99 percent water and 1 percent salts," says internal medicine physician Shoshana Ungerleider, MD. Sweat is also naturally odorless — the smell comes from bacteria on your skin and clothes interacting with the sweat to produce an odor.

There are two main types of sweat, per the Cleveland Clinic:

  • Eccrine sweat. This is the common type of light, watery sweat you can expect during exercise, a hot day, or general exertion.
  • Apocrine sweat. This type of sweating is triggered by stress hormones, which raise your heart rate and blood pressure, bumping up your temperature. Usually coming from the armpits, head, or groin area, apocrine sweat feels thicker on the skin and actually contains some fat.

Why Do Some People Sweat More Than Others?

"There are a variety of reasons why some sweat more than others including: exercise, warmer and more humid weather, consuming alcohol, eating spicy foods, medications, anxiety, hormones (decreases in estrogen from menopause), caffeine intake and others," says Dr. Ungerleider.

However, some people do sweat excessively and may have a condition called hyperhidrosis, where the body's sweat glands are overactive. Hyperhidrosis leads people to perspire more than others, and Dr. Ungerleider says the condition can be challenging and does impact quality of life.

There are two main types of hyperhidrosis, and it can be linked to a number of factors: genetics, medical conditions, medication, spinal-cord injury, metabolic diseases like hyperthyroidism and diabetes, or anxiety and stress, according to the Cleveland Clinic. The two types of hyperhidrosis are as follows:

  • Focal hyperhidrosis. Also known as primary hyperhidrosis, this is an inheritable skin condition usually affecting only the armpits, hands, feet, and head. Most people with excessive sweating will have this type of hyperhidrosis, and it tends to show up before age 25.
  • Generalized hyperhidrosis. Also called secondary hyperhidrosis, this kind of excessive sweating is caused by other medical problems, like diabetes or Parkinson's disease. Some medications, like naproxen, may also increase your sweating. Generalized hyperhidrosis is most common in adults.

There is no cure for hyperhidrosis, but symptoms can be managed with your doctor. Cleveland Clinic recommends options including lifestyle changes (like switching to more breathable clothing); aluminum-based antiperspirants; oral medications like glycopyrrolate, oxybutynin, antidepressants, or beta blockers; or prescription-strength wipes to reduce sweating. But be sure to consult your doctor before starting any new course of medication or treatment. They can better help you come up with sweat solutions that are specific to you.

Why Do Some People Struggle to Sweat?

On the other side of the spectrum exists a condition called anhidrosis, the absence of sweating, which can put you at risk for overheating or even life-threatening complications.

There are many causes of anhidrosis, including but not limited to:

  • Sweat glands not working properly
  • Skin damage (burns, radiation therapy)
  • Damaged sweat glands (including scarring or surgery)
  • Nerve damage or other nerve conditions
  • Dehydration
  • Certain medications like tricyclic antidepressants, antihistamines, opioids, and others

Those with anhidrosis may have little to no sweating, dizziness, muscle cramps, weakness, flushing, or feeling hot without being able to cool off, per Cleveland Clinic. Important to note is that anhidrosis, sometimes referred to as hypohidrosis, doesn't necessarily mean you can't sweat at all — it may be limited to a certain area of the body.

"Another pattern of anhidrosis is lack of sweat or very little sweat in certain body areas, but heavy sweating in other body areas. This happens because your body is trying to make up for the lack of sweat in one or more other body areas," says Cleveland Clinic. This tends to be less dangerous because the body still has a way to cool down.

There is no cure for anhidrosis, but you should work with your doctor, stay hydrated, and try to keep cool.

"If you think you sweat too much or if sweating is impacting your quality of life, speak to your doctor about it," recommends Dr. Ungerleider. "There are specialists like dermatologists who can evaluate you and decide if treatment is right for you."