Rosanne Leipzig, MD, PhD, is Professor and Vice Chair of the Brookdale Department of Geriatrics and Adult Development at the Icahn School of Medicine at Mt. Sinai in New York, N.Y. She also serves as Editor-in-Chief of the monthly publication Mount Sinai School of Medicine Focus on Healthy Aging.

Summer is here, with its warm (and sometimes too hot!) weather and the opportunity to spend more time outdoors. It can be great for socialization, exercise, vitamin D levels, mood, and even sleep—if you remember two things that can help you ward off skin cancer, heat exhaustion, heat stroke, and more.

1. The first is that you need to protect yourself from the sun. Your best option is a sunscreen with a sun protection factor (SPF) of at least 15 (and preferably 30). Make sure it’s broad spectrum, which means it will shield you from the sun’s ultraviolet-A (UVA) and ultraviolet-B (UVB) rays. And apply the product properly! A smear isn’t sufficient—you need at least a shot-glass full, applied to all exposed skin. Re-apply every two hours, and always after swimming or sweating excessively.
2. The second is that older adults are more vulnerable to heat-related illness. Most of the 200 or so Americans who die each year from health problems caused by heat and humidity are 50 and older.

We’re susceptible to these conditions because as we age, we lose the ability to adequately respond to heat. Our bodies are programmed to maintain a temperature of about 98.6 degrees Fahrenheit (°F). If this temperature is exceeded, the body tries to cool itself through dilation of the blood vessels in the skin (which brings heat from the body core to the skin) and through increased perspiration (evaporating sweat helps cool us). However, as we age, our built-in cooling mechanism becomes less efficient—blood vessels don’t dilate as well, and we sweat less. We’re also less likely to feel thirsty, which means we run the risk of dehydration.

Hot-weather factors can be more harmful in people with health problems.

Health Issues Can Add to Summer Illness Risk

The hot-weather factors described above can be more harmful in people with health problems. For example:

• High heat and humidity have been implicated as a possible factor in heart attack, so individuals with heart disease need to take even more care to keep cool.
• Certain medications may increase the effects of heat by interfering with our cooling mechanism—for example, diuretics and beta-blockers, which are used to treat heart problems, and anticholinergic drugs, which are used to treat overactive bladder, Parkinson’s disease, and other disorders.
• Some of the older antidepressants, like amitriptyline (Elavil) and imipramine (Tofranil), can raise the body’s temperature while also sedating you so that you may not be aware of feeling too hot.
• Some antihistamines (used to treat allergies) can reduce the production of sweat.

How to Fend Off Heat Exhaustion, Dehydration, Headaches, and More

The dangers posed by the sun’s rays and summer’s heat mean that it’s vital for you to recognize the signs and situations that could mean you’re too hot.

Signs of heat exhaustion include headaches, dehydration, weakness, dizziness, fainting, and muscle cramps. If you experience these symptoms in hot weather, seek medical advice, particularly if you have heart problems or high blood pressure. Also, take steps to cool yourself down by going indoors (preferably to a room with air conditioning or a fan) and by drinking plenty of water.

The more serious condition of heat stroke develops if body temperature rises to 105° F or higher; it can cause death or permanent disability. Symptoms of heat stroke include a rapid pulse, severe headache, dizziness, nausea, confusion, and the absence of sweat. In short, heat stroke is a medical emergency, so make sure you quickly get medical assistance.

Stay hydrated to avoid heat exhaustion; choose clear fluids (what’s better than water?) over caffeinated beverages.

3 Key Hot Weather Tips

To protect yourself from heat-related illness, keep these three simple measures in mind.

1. Drink plenty of clear fluids (avoid caffeinated beverages and alcohol, as these will dehydrate you).
2. Dress in light-colored, loose clothing (don’t overdress).
3. Avoid extended sun exposure or strenuous activities in high temperatures (get exercise in the mornings or evenings, when it’s cooler).

These precautions can significantly reduce your risk of illness and ensure that your summer is safe and enjoyable.

Rosanne Leipzig, MD, PhD, is Professor and Vice Chair of the Brookdale Department of Geriatrics and Adult Development at the Icahn School of Medicine at Mt. Sinai in New York, N.Y. She also serves as Editor-in-Chief of the monthly publication Mount Sinai School of Medicine Focus on Healthy Aging. Visit her website at rosannemd.com.

Originally published in 2017, this post is regularly updated.