Even if you’re constantly taking swigs from your trusty reusable water bottle, you may not be getting enough hydration, especially in extremely hot weather — and it’s well-documented that dehydration can be dangerous and sneak up quickly when temperatures are very high. Unfortunately, drinking a ton of water alone doesn’t always do the most to hydrate you, because you also need to make sure you’re getting in enough electrolytes.

For a previous HuffPost story about combatting heat exhaustion, Dr. Haris Vakil, a fellowship-trained primary care sports medicine physician with a board certification in family medicine and certificate of added qualification in sports medicine, said, “Staying hydrated with a balance of electrolytes, or salt loading leading up to the event, in conjunction with water is essential. Most individuals only drink water, and dilute necessary internal balancing salts, and cause more harm when ignoring electrolyte replacement.”

According to Cleveland Clinic, key electrolytes include sodium, magnesium, potassium, calcium, chloride, phosphate and bicarbonate. You can get electrolytes through foods like leafy green vegetables, bananas and more, but when it’s not practical to bring food on the go — or you’re looking for a sugar-free alternative — electrolyte drink packets added directly to your water can boost your electrolytes and deliver fast hydration.