As Americans come to commemorate the nation’s victory 250th anniversary Saturdaytemperatures in large parts of the country will be anything but festive. An intense heat wave is gripping the eastern and central United States, exposing millions of people to temperatures above the seasonal average and putting them at risk of heat-related illnesses.
Up and down the East Coast and central United States, the mercury could exceed 100 degrees Fahrenheit (38 degrees Celsius), with some places, like New York Cityreaching 115 degrees F (46 degrees C) during the day. The easiest way to stay safe is to stay indoors in air-conditioned spaces with easy access to cold water– both for drinking, for showering or for wetting towels to refresh your body. But it won’t work for everyone.
Most public health messages during a heat wave focus on two heat-related illnesses: heat exhaustion and heat stroke. And for good reason: heatstroke, the most serious illness, can occur when the body’s internal temperature exceeds 40 degrees C (104 degrees F) or by extreme dehydration. Heat stroke can be fatal without immediate medical attention.
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But there’s another condition you need to be aware of: hyponatremia, which results in low sodium levels in the blood and is often linked to alcohol consumption. too much water. Hyponatremia is barely mentioned in heat-related public health messages: I had never heard of it until I was diagnosed with it.
In cases of hyponatremia, your body’s salt water balance, crucial for the proper functioning of cells, is disrupted. When salt levels in your blood drop, your cells swell. In its early stages, hyponatremia is often confused with heat exhaustion, leading people to drink more water to cool down. But this only makes the swelling worse, quickly causing other parts of the body, including the brain, to swell, which can cause loss of consciousness, seizures, and in some cases, death.
Here are three science-based tips you can use to stay safe in the heat this Independence Day weekend.
Know the signs of heat-related illness
Heat exhaustion is the first step toward heat stroke; it is caused by overheating and dehydration, more specifically by the loss of salt and water through sweat. People suffering from heat exhaustion typically feel dizzy, begin to sweat profusely, have a rapid pulse, and may feel nauseous.
Heatstroke is the most dangerous condition. If heat exhaustion is left untreated, it can progress to heat stroke. This is a potentially life-threatening condition. People suffering from heatstroke may feel confused, unable to speak properly, and agitated. Some people breathe heavily, notice their heart rate racing, and may even lose consciousness. Unlike the early stage of this disease, they may not sweat at all. If left untreated, extreme heat inside the body causes cells to “cook,” leading to organ failure, brain swelling, and often a heart attack.
Another heat-related condition (although not always heat-related!) is hyponatremia. It may present with early symptoms such as muscle cramps, nausea, headaches and fatigue. If left untreated or, as in many cases, made worse by the instinct to drink more water to try to relieve these heat exhaustion-like symptoms, the signs become more striking: People may suffer seizures, feel confused, hallucinate, or fall into a coma. Just hours after the disease develops, hyponatremia can cause the brain to swell to the point of herniation, pushing the swollen brainstem into the spinal cord, which is often fatal.
Drink water, but not too much
The U.S. Centers for Disease Control and Prevention (CDC) recommends that people drink water to avoid dehydration. It states that people working outdoors or exercising in the heat should drink eight ounces (one cup) of water every 15 to 20 minutes. For an eight-hour workday, that would equate to drinking at least 1.66 gallons, or more than 6 liters of water. The CDC also warns that thirst is a poor indicator of dehydration, but some physiologists and wilderness medicine experts say the advice isn’t always helpful because it can lead to overhydration.
It’s important to note that the CDC warns that drinking more than 48 ounces of fluid in an hour could cause your salt levels to drop to dangerously low levels. Remember that liquid can mean water, juice, tea, soda or any other beverage.
The CDC also notes that to be truly hydrated, you need to eat regularly in the heat to replenish salt levels. And for those wondering if a sports drink like Gatorade might be effective enough to hydrate you while protecting you from hyponatremia, you’re wrong. Commercially available sports drinks typically contain less than 20% of the recommended amount of salt an adult should consume per day. It’s just not salty enough to raise your blood salt levels. Eating a one-ounce serving of salted pretzels is a better choice.
In extreme cases of hyponatremia, doctors give patients extremely salty solutions, such as half a cup of broth made from four standard beef broth cubes. This amount of salt is much more effective in getting your salt levels back to where they need to be.
Cool your body
An effective way to prevent heat illness is to stay indoors, with windows and blinds closed – light means heat – in an adequately air-conditioned space. Depending on where you live, your city may provide cooling stations where you can access air conditioning even if you don’t have it installed in your home. The National Center for Healthy Housing has a state directory to help you find a local cooling center.
If you don’t have air conditioning but do have fans, these can provide a cooling breeze in certain conditions. If the air outside your home is cooler than inside, place the fan near an open window and point it inside. If possible, stand in front of the fan and, to really cool down, wear wet clothes during this time.
Sometimes it’s more effective to point the fan outside at night, when temperatures naturally drop. This allows the fan to push hot air out of the room and draw cooler air in through the open window.
If you go outside, wear a hat, loose clothing and sunscreen and reapply regularly. Stay in the shade as much as possible and bring a portable fan if you can. Bring a cold, damp face towel or an ice pack to put on your neck or pulse points to help your body stay cooler in the heat. Avoiding alcohol and caffeine can also help your body maintain its internal temperature regulation.
Some research suggests that soaking your feet in a bath of ice water can help cool your body’s core. Taking regular cool showers and baths, wetting your clothes or towels with cold water, and putting your pillowcases in the refrigerator or freezer can all help to further cool your body and hopefully get a good night’s sleep.
