amount of water to drink in a day
Aim to drink one or two cups of water before you exercise, and sip about a half to one cup of water every 15 minutes while you're working out. If you're sweating really hard, or if you're out in the heat, you might need more—listen to your body. Here’s Exactly How Much Water You Should Drink Every Day. 1  All fluids count toward your daily intake, not just plain old H20. 2  So does the water you get from the foods you eat. 3  On the flip side, some foods and drinks can increase how much water you need. You are probably all aware of the “cardinal rule” that says adults should drink six to eight 8-ounce glasses of water per day. The truth is, this is an estimate and the actual amount you should be drinking per day can vary quite significantly. There are multiple factors that can impact how much water you should be drinking. Weight But even a healthy person's water needs will vary, especially if you're losing water through sweat because you're exercising, or because you're outside on a hot day. If you're wondering how much water should you drink on those occasions, speak with your doctor, but a general rule of thumb for healthy people is to drink two to three cups of water per hour, or more if you're sweating heavily. Your personal fluid requirements also can vary each day, depending on the other things you're doing, eating, and drinking. The Institute of Medicine recommends that women get 2.7 liters—that’s 11 cups—of water per day. Note, they don’t say you need to drink 11 cups of water a day. That includes all sources of water—from a basic glass of tap, to a cup of coffee, to the water content of the foods you eat (which, the IOM estimates, makes up about one-fifth of your daily fluid intake). Too much caffeine can give you the jitters or keep you from sleeping. And, alcohol intake should be limited to one drink per day for women, and 1-2 drinks per day for men. To ward off dehydration, drink fluids gradually, throughout the day. An easy way to do this is to have a drink at each meal, as well as socially, or with medicine. And know that you also get fluids from water-rich foods, such as salads, fruit, and applesauce. – By Heidi Godman The Harvard Medical School Special Health Report 6-Week Plan for Health Eating notes that water has many important jobs, such as: 1  carrying nutrients and oxygen to your cells. 2  flushing bacteria from your bladder. 3  aiding digestion. 4  preventing constipation. 5  normalizing blood pressure. 6  stabilizing the heartbeat. 7  cushioning joints. It's possible to take in too much water if you have certain health conditions, such as thyroid disease or kidney, liver, or heart problems; or if you're taking medications that make you retain water, such as non-steroidal anti-inflammatory drugs (NSAIDs), opiate pain medications, and some antidepressants. In short, the equation tells you to take half your body weight, and drink that amount in ounces of water. In the example, notice that you should be drinking more than 12 glasses of water, not eight! Exercise. Your exercise habits affect the amount of water you should be drinking, as well. The American College of Sports Medicine recommends adding 12 ounces of water to your daily intake for every 30 minutes that you plan to work out. You've probably heard you're supposed to drink at least eight 8-ounce glasses of water daily. That's almost enough to fill a 2 liter bottle—which even the most diligent water-drinkers may find daunting. But the classic advice is not the end-all-be-all of water intake. In fact, it's pretty misleading.
Adults should drink six to eight 8-ounce glasses of water per day.