Getting enough water also is important. Many experts recommend at least eight 8-ounce glasses of water daily—more if you exercise frequently or are exposed to extremes of heat and cold. The 2010 Dietary Guidelines for Americans emphasize drinking more water and other calorie-free beverages, along with fat-free or low-fat milk and 100 percent fruit juices, instead of calorie-packed regular sodas.
Iron helps to create the hemoglobin that carries oxygen in your blood. It’s also important to maintaining healthy skin, hair, and nails. Due to the amount of blood lost during menstruation, women of childbearing age need more than twice the amount of iron that men do—even more during pregnancy and breastfeeding. However, many of us aren’t getting nearly enough iron in our diets, making iron deficiency anemia the most common deficiency in women.
As the science of nutrition continually evolves, researchers recognize that nutrients needed to maintain a healthy lifestyle must be tailored to the individual for maximum effectiveness. Recognizing that people are not all alike and that one size does not fit all when it comes to planning and achieving a healthful diet, the Institute of Medicine's dietary guidelines, titled "Dietary Reference Intakes for Macronutrients," stress the importance of balancing diet with exercise and recommends total calories based on an individual's height, weight and gender for each of four different levels of physical activity.
Fluids: Fluid needs increase as women age. The reason: Kidneys become less efficient at removing toxins. “Drinking more fluids helps kidneys do their job,” Schwartz says. “Unfortunately, thirst signals often become impaired with age, so people are less likely to drink enough water and other fluids.” Rather than fret about how many glasses to drink, Frechman says, check the color of your urine. "It should be clear or very pale colored. If it becomes darker, you need more fluid.”