Hydration

In the winter it's easy to lose track of how dry the air is until the headaches begin.

Water: How much should you drink every day?

About 15.5 cups (3.7 liters) of fluids for men
About 11.5 cups (2.7 liters) of fluids a day for women

Exercise. If you do any activity that makes you sweat, you need to drink extra water to cover the fluid loss. It's important to drink water before, during and after a workout. If exercise is intense and lasts more than an hour, a sports drink can replace minerals in your blood (electrolytes) lost through sweat.

Drink a glass of water or other calorie-free or low-calorie beverage with each meal and between each meal.
Drink water before, during and after exercise.
Drink water if you're feeling hungry. Thirst is often confused with hunger.