B12: Like folic acid, B12 is essential for healthy nervous system development and function. Pregnant women who are vegans or vegetarians may fall short on B12, since it is present in animal protein and to a lesser extent in dairy. Teenage and adult women need 2.4 mcg. Recommended levels rise to 2.6 mcg for pregnant women and 2.8 mcg for lactating women.
Iron is one of the keys to good health and energy levels in women prior to menopause. Foods that provide iron include red meat, chicken, turkey, pork, fish, kale, spinach, beans, lentils and some fortified ready-to-eat cereals. Plant-based sources of iron are more easily absorbed by your body when eaten with vitamin C-rich foods. So eat fortified cereal with strawberries on top, spinach salad with mandarin orange slices or add tomatoes to lentil soup.
When you do high-intensity interval training (and if you’re not, you should be!), follow a 2:1 work-to-rest ratio, such as sprinting one minute followed by 30 seconds of recovery. [Tweet this secret!] According to several studies, the most recent out of Bowling Green State University, this formula maximizes your workout results. The BGSU researchers also say to trust your body: Participants in the study set their pace for both running and recovery according to how they felt, and by doing so women worked at a higher percentage of their maximum heart rate and maximum oxygen consumption than the men did.
Most Americans get far more protein than they really need. In theory, that may not be wise. Like carbohydrates, protein provides 4 calories per gram, and excess calories from any source will be stored as body fat. Excess dietary protein increases calcium loss in the urine, perhaps raising the risk for osteoporosis ("thin bones," more a worry for women) and kidney stones (a particular worry for men).
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.”