You may have heard that drinking cold water can help you burn more calories throughout the day, but unfortunately, that tip is merely myth. Although it makes sense to think that your body would use more energy to heat the water to its core temperature, studies have found that the amount of calories burned (about four to seven calories per glass) is too minimal to actually make a difference. However, drinking cold water does offer benefits outside of weight loss.
According to Jacqueline Schaffer, MD, a board-certified medical doctor, "cold water can increase blood circulation on the skin's surface specifically," which can promote the appearance of glowing skin. Additionally, research has shown that drinking cold water during exercise can decrease dehydration and make you feel less tired, helping you work out longer as a result. The reason being that it helps keep your core body temperature cool.
But regardless of what temperature your water is, the most important thing is that you're drinking water at all. Dehydration is not something to take lightly: it can cause fatigue, irritability, muscle cramps, dizziness, and headaches, and even cause your metabolism to slow down without the ability to remove waste. A good rule of thumb is to to drink about half of your bodyweight (in pounds) in fluid ounces.
Moral of the story: just drink water. Period.