Early in the day, drink plain water. As you begin to sweat more heavily, switch to drinks containing electrolytes to replenish those you’ve sweated out: coconut water, Smartwater, Gatorade, Powerade, things like that. Electrolytes are minerals in your body such as sodium and potassium that have an electric charge, and your body needs them to function. When you sweat them out, you have to replace them.
You can also buy electrolyte tablets, like NUUN tablets (7), and drop one in a bottle of plain water. Fruit smoothies are a favorite of mine when the heat is killing me. As an alternative that you don’t need to drop into your water, try chewable SaltStick Fastchews ($ 3). Get something icy with a bit of coconut water, almond milk, and fruit solids to give you an energy boost and cool you down from the inside. Keep drinking them throughout the day to stay hydrated — small sips regularly, at least. And if your urine gets dark, it’s time to up your intake.
If your power goes out or if you’re outdoors, pick up an insulated cooler and some loose ice to keep your drinks chilly. This Igloo Laguna Ice Chest ($ 20) is nothing fancy, but it’s a time-tested design that excels at its main job without any frills: keeping beverages cold for a long time.
Contrary to popular advice, coffee and soda are fine to drink. The amount of caffeine in them is low enough relative to the amount of water that they’ll still hydrate you if you’re dehydrated. Beer is fine too, so long as it’s a session beer (about 3 to 4 percent alcohol by volume) and not one with a high ABV. Just pace yourself and don’t drink too many. Studies that play up beer’s diuretic effects — that is, it makes you urinate — tend to test with higher-ABV beers (5 percent or more) and on test subjects who are already well hydrated or hyper-hydrated. Even if such a case, negative effects on your hydration would be close to negligible — unless you’re hitting a lot of them or drinking those fancy, way-high ABV beers like barley wines and tripels.
Hard liquor is not a good idea. The alcohol content is too high relative to the overall volume of liquid in a serving.
What to Eat in the Heat
You can pee clear and still be dehydrated. Plain water, on an empty stomach, speeds through the body. The digestive system recognizes that there are no nutrients to absorb from the water, and without food to digest — which requires water — the body gives it the green light to pass through the body as fast as it wants. It’s like a high-occupancy-vehicle lane for fluids. It doesn’t make drinking water useless — definitely keep sipping often since you are absorbing some of it. You’ll just absorb more if there’s food in your belly that will put the brakes on that flood of water, allowing your body to absorb more of it.