Why women face a higer risk of death from heat-related illnesses

Heat stroke is a life-threatening condition that causes your body to overheat. It’s defined as a body temperature above 104 degrees Fahrenheit. Heat stroke occurs when your body is unable to cool itself down.

Your hypothalamus, a part of your brain that controls many bodily functions, sets your core body temperature. For most of us, that temperature is set at about 98.6°F.

However, if your body absorbs more heat than it releases, your internal temperature will rise above this point.

Heat stroke can cause brain swelling, kidney and liver failure, and nerve damage, as well as reduced blood flow to the heart. Any of these can become life-threatening very quickly.

Older people are more vulnerable to heat-related illnesses, including heat exhaustion and heat stroke. But, medical experts have known that women are at a higher risk of dying from a heat-related illness than men. The “why” has been the missing part of the puzzle until now…

Women’s vulnerability to heat begins early

Researchers at Penn State University tested the heat thresholds of 72 participants between 40 and 92 years of age by placing them in a specialized environmental chamber. But first, they each swallowed a tiny devise encased in a capsule that would measure their core temperature throughout the experiment.

The participants engaged in light physical activity to simulate the effort of minimal day-to-day tasks — the types of things people would need to do even during a heat wave.

Gradually, the researchers increased the temperature and humidity in the chamber until participants’ bodies could no longer adequately cool themselves, and their core temperature began to rise.

What they found was that the physiological responses of middle-aged women were similar to the responses seen in older men in the study.

In other words, older women are at greater risk than older men, and middle-aged women are as vulnerable as older men.

Support your body’s cooling system

The wisest way to avoid heat-related illnesses, including heat stroke, is to stay out of the heat. But that’s not always possible. Staying hydrated, out of direct sunlight and wearing loose-fitting clothing can help.

But as we just read, women may need more help staying cool…

A few years ago, I learned how the circulation system not only supplies blood throughout the body but also acts as a cooling system.

When the body increases blood flow at the skin level — and that action is combined with sweat on the skin’s surface — it helps the body cool down.

With age, however, the blood vessels have a harder time dilating. This means blood doesn’t circulate efficiently enough to dissipate heat — much like a car’s engine that’s running without enough coolant.

To widen blood vessels, the body depends on the production of nitric oxide (NO). However, the body produces less with age and for women there is a double whammy: the loss of estrogen exacerbates the loss of NO.

Luckily, NO production can be supported by eating foods rich in either dietary nitrates, L-arginine or the B vitamin, folate.

Nitrates are converted to nitrites and then nitric oxide in the gut, bloodstream and various organs — anywhere there are blood vessels depending on it to help widen and support blood flow, including the skin.

Foods known to increase NO include:

• Beets
• Leafy greens
• Celery
• Radishes
• Watermelon
• Nuts and seeds
• Meat
• Eggs
• Dairy

You’d need to eat a little every day as these foods help the body make a supply of nitric oxide that lasts roughly about 24 hours.

Take your risk of heat-related illnesses seriously and prepare ahead to stay safe.

Sources:

Older women more vulnerable to heat than their male peers, researchers find — Science Daily

Sex differences in heat stress vulnerability among middle-aged and older adults (PSU HEAT Project) — American Journal of Physiology

Heatstroke — Cleveland Clinic