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With a summer of record heat, hydration is more important than ever. If you don’t drink enough fluid to produce enough sweat on a hot day, you may be more susceptible to heatstroke. Dehydration can be caused by extreme heat, but it can also exacerbate other heat-related conditions like heat cramps.
Fluid absorption is therefore crucial, but hydration can go beyond the simple consumption of water. The popular belief that we all need to drink eight cups a day to be truly hydrated persists, though it has been debunked over and over again.
“There’s really no data behind the eight glasses of water a day,” said Dr. Dan Negoianu, a nephrologist at the University of Pennsylvania. For example, “Just because your urine is dark doesn’t mean you’re dehydrated.”
Being hydrated simply means consuming enough fluids to the point of not feeling thirsty, Dr. Negoianu said, and that amount varies for everyone.
There are plenty of things besides plain water that will keep you hydrated, experts say: This includes the foods and drinks that appeal to you, the things that will make you seek them out constantly. Here are some suggestions.
Find your favorite fruits, vegetables and drinks
“We think we need to drink lots of water all the time because we hear it all the time,” said Tamara Hew-Butler, a sports medicine scientist at Wayne State University who specializes in fluid balance. “You have to drink your eight glasses – hydrate, hydrate, hydrate.”
But any food or drink that contains liquid will be hydrating, she said: “Your body doesn’t care where the hydration comes from, it just needs the liquid.”
Fresh fruits and vegetables are ideal sources because not only do they tend to be high in water content, but they also contain fiber, which provides other benefits for your diet and health. Melons, such as watermelon, honeydew or cantaloupe, are particularly juicy. Strawberries, oranges, grapes, cucumbers and celery are also filled with water.
Drinks of all kinds can be hydrating. Juice, milk, tea, and coffee each contain liquids that your body can use. High-sugar drinks may not be the best nutritional choice, but research shows that sugary drinks are just as effective as water at delivering fluids to your system. In the heat of summer, of course, frozen desserts like popsicles and sorbets are convenient vessels for liquid consumption.
“You can meet and exceed your daily fluid requirements through the ingestion of high-moisture foods and beverages without drinking a single glass of plain water,” Dr. Hew-Butler said in an email.
Caffeinated beverages can also be hydrating. Although caffeine is often thought of as a diuretic or dehydrating substance, research shows that drinking coffee or other caffeinated beverages has about the same hydrating or dehydrating effects as just drinking coffee. water, especially if you are a regular caffeine consumer.
If you consume a significant amount of caffeine after a long period without caffeine, you might experience a small stab of dehydration, said Kelly Hyndman, a researcher at the University of Alabama at Birmingham who studies kidney function and fat retention. water. But otherwise, caffeine won’t cause dehydration, she added — at least not at the levels people typically consume.
Don’t be afraid of salty foods
You’ve probably heard that salty foods dehydrate, but that’s not strictly true, says Dr. Hyndman.
Our body is constantly trying to maintain a salt-water balance, which it does with the help of a number of hormones. One of the most important of these is antidiuretic hormone, or ADH.
When we eat a lot of salty foods at once, our brain secretes ADH, which in turn tells our kidneys to retain water, preventing us from urinating excess fluid. At the same time, the brain secretes another hormone, vasopressin, which is linked to the feeling of thirst. Together, all of these hormones signal that you need more fluids. Consuming too many salty foods is only a problem if you also ignore your thirst cues, Dr. Hew-Butler said.
If you’re looking for salty foods that hydrate, olives and pickles are acceptable choices, even though people rarely consume large quantities. Soup, especially with water-based broths, can also help replenish your water.
But what is really dehydrating is alcohol. “Alcohol suppresses ADH,” Dr. Hyndman said. So when you consume it, “you don’t have that hormone that tells your kidney to reabsorb water” and all the liquids you consume go straight through you.
Make sure children, the elderly and people with medical needs are satisfied
“Most of us who say we’re dehydrated probably aren’t,” Dr. Hyndman said. While there are likely to be people walking around a little dehydrated, she added, the majority of people are adequately hydrated or even a little overhydrated. If you complain about having a small bladder, or if you urinate more often than you would like, maybe you don’t need to consume as much fluid – it just leaks through you.
Those who need to be most diligent about actively hydrating are children, the elderly, and people with underlying health conditions, Dr. Hyndman said.
The rest of us just need to have a drink or eat liquid-filled foods when we’re thirsty, Dr. Hew-Butler said, and trust our instincts. “We don’t need to think about it too much,” she added.
“I think the ‘drink when you’re thirsty’ rule is hard to break,” Dr. Negoianu said, except for medical conditions or ultra-harsh environments that could lead to abnormal water loss. “As far as how much water you need, it’s like Goldilocks and the Three Bears.” Just as Goldilocks had to decide for herself which porridge was right, each person must find the level of hydration that is right for them and their situation.
Sound produced by Kate Winslet.