The Hidden Meaning of Hot Flashes

You wake up from a deep sleep drenched in sweat and must change your sheets and pajamas — again. Or you're doing errands or visiting with a friend, suddenly feeling like your body is on fire. Maybe you remember these hot flash scenarios or are still experiencing them. Hot flashes are annoying, embarrassing and downright disruptive, but that's not all.

A growing body of research suggests hot flashes may be the canary in the coal mine for the health of your heart and brain.

Hot flashes are sudden surges of intense heat that affect more than 80% of women during the transition to menopause and may continue for years after their last period.

These happen when the brain mistakenly thinks the rest of the body is overheating, triggering a chain of reactions to reduce the warmth, including sweating, flushing and chills. 

Experts are not exactly sure what causes hot flashes, but it's thought that declining estrogen levels disrupt the body's "thermostat," a group of brain cells that control core temperature. Hot flashes can last between 30 seconds and 10 minutes, but their more significant effects linger for decades.

Hot flashes are connected to an increased occurrence of several traditional risk factors for cardiovascular disease, including high blood pressure, insulin resistance, diabetes and elevated cholesterol and triglyceride (fat) in the blood.

"While there is no research that proves hot flashes actually cause cardiovascular disease, there is mounting evidence of a link," says Samar R. El Khoudary, Ph.D., professor at the University of Pittsburgh School of Public Health Epidemiology Data Center. 

Despite the lack of definitive studies to determine a cause-and-effect relationship between hot flashes and heart and brain health, research suggests hot flashes shouldn't be brushed off as passing inconveniences.

El Khoudary was one of the investigators involved with the Study of Women's Health Across the Nation (SWAN) that followed a group of more than 3,300 ethnically diverse women for up to 22 years. The study found that hot flashes were associated with a greater risk for cardiac "events" such as heart attack and stroke. Even when traditional risk factors and levels of estrogen — considered protection against cardiovascular disease — were factored in, the findings stood.

When it comes to hot flashes, timing matters. "The SWAN study showed hot flashes that start earlier in life or persist for longer, or both, increased the chances for cardiovascular events," El Khoudary says. 

Women in the study with frequent hot flashes had a 50% higher chance of an event, and those with regular and persistent hot flashes experienced a 77% greater chance. The authors concluded that hot flashes may represent a female‐specific risk for cardiovascular disease.

Hot flashes that happen when you're trying to sleep, called night sweats, may be connected to later cognitive decline, including Alzheimer's disease and other types of dementia. For example, a 2022 American Academy of Neurology study found that women with frequent night sweats had more brain lesions typically associated with cognitive impairment. 

The study included 226 women, ages 45 to 67, who were free of hormone therapy. It considered their age, race, education, smoking, body mass index, blood pressure, insulin resistance, and blood cholesterol and triglyceride levels. However, most subjects were white and in the early postmenopausal stage, so the findings may not apply to all women.

You may have been plagued by hot flashes leading up to menopause. Perhaps you continue to have hot flashes years after menopause occurs, which isn't uncommon. You can't change the fact that you're prone to hot flashes, but you can take steps to minimize the effects of traditional risk factors that they influence.

If you're having hot flashes, talk to your doctor about how best to reduce their frequency and intensity so that you feel better and have more energy to devote to your health. Hormone replacement therapy and other medications, such as antidepressants, can help reduce hot flashes. 

Different approaches, including cognitive behavior therapy, acupuncture and regular physical activity, may help alleviate the negative feelings, including anxiety and depression, caused by persistent hot flashes. Certain eating habits can help, too.

"Some women find relief from hot flashes by avoiding alcohol and caffeine and including soy foods, such as tofu, edamame and unsweetened soymilk, on a regular basis," says Hillary Wright, co-author of "The Menopause Diet Plan."

In addition, women with obesity or who smoke are at greater risk for hot flashes and may benefit from lifestyle changes to lose weight or quit smoking.

Hot flashes or not, the American Heart Association stresses the need for women to track their blood cholesterol, blood pressure, blood glucose and body weight, as these numbers can creep upward in postmenopause.

"Nutritious foods, regular exercise and stress reduction are among the best ways to head off the trouble that hot flashes and other risk factors may cause," Wright says. A balanced, plant-based diet that's low in saturated fat and sodium and includes two servings of seafood weekly goes a long way to support your heart and your brain.

El Khoudary suggests discussing your hot flash history with your doctor, who may need to be made aware of the growing evidence of a connection between hot flashes and cardiovascular health. "Women with a history of hot flashes warrant attention from medical professionals because they may require more screening to help them to stay as healthy as possible," she says.

Elizabeth M. Ward is a registered dietitian nutritionist (RDN), writer, and award-winning nutrition communicator. Her work has appeared in WebMD, Men’s Health, and EatThis.com.

Ward is the author or co-author of eight nutrition, food, and health books. Her most recent book is The Menopause Diet Plan, A Natural Guide to Hormones, Health, and Happiness (co-author). Ward lives in the Boston, MA, area. Read More