There's not much doubt about this one: Women need more iron than men, because they lose iron with each menstrual period. After menopause, of course, the gap closes. The RDA of iron for premenopausal women is 18 mg a day, for men 8 mg. Men should avoid excess iron. In the presence of an abnormal gene, it can lead to harmful deposits in various organs (hemochromatosis). Since red meat is the richest dietary source of iron, it's just as well that men don't need to wolf down lots of saturated fat to get a lot of iron.
Stress can wreak serious havoc on our bodies, but we actually need stress to a certain extent. For example, if we were running from a bear, we would need our stress response to kick in full force. We would start breathing faster, sending more oxygen to muscles to fuel movement, then our bodies would release stress hormones from our adrenal glands (cortisol) to heighten our focus by tapping into energy reserves for fuel so we could flee the danger. Cortisol isn’t always the bad guy, but when this response is high and chronic it tells your body to eat more than it “needs” because it’s thinking much more about survival, not stress over a work deadline or relationship woe. Cortisol is needed, but high levels of cortisol over time will contribute to those mentioned health impacts, especially abdominal weight gain! The problem is when we’re actually not in danger and our bodies are living in this state chronically. THIS is the magic piece of the puzzle – learning how we can turn off that heightened stress response when it’s not needed.
While women tend to need fewer calories than men, our requirements for certain vitamins and minerals are much higher. Hormonal changes associated with menstruation, child-bearing, and menopause mean that women have a higher risk of anemia, weakened bones, and osteoporosis, requiring a higher intake of nutrients such as iron, calcium, magnesium, vitamin D, and vitamin B9 (folate).

To help you learn how to eat healthfully, start with the U.S. Department of Agriculture's (USDA) dietary guidelines system, which you can find at The MyPyramid system, which looks somewhat like the familiar food pyramid of old, offers guidance based on individual needs and replaces "serving" recommendations with actual amounts of food. It also emphasizes the importance of balancing nutritious (and tasty!) food choices from all food groups every day with daily physical activity.
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.
For healthy bones and teeth, women need to eat a variety of calcium-rich foods every day. Calcium keeps bones strong and helps to reduce the risk for osteoporosis, a bone disease in which the bones become weak and break easily. Some calcium-rich foods include low-fat or fat-free milk, yogurt and cheese, sardines, tofu (if made with calcium sulfate) and calcium-fortified foods including juices and cereals. Adequate amounts of vitamin D also are important, and the need for both calcium and vitamin D increases as women get older. Good sources of vitamin D include fatty fish, such as salmon, eggs and fortified foods and beverages, such as some yogurts and juices.

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.”