Iron: Essential for healthy blood cells, iron becomes especially important when girls begin to menstruate. With each period, a woman loses small amounts of iron. “About 10% of American women are iron deficient,” says Dorothy Klimis-Zacas, PhD, a professor of nutrition at the University of Maine and co-editor of Nutritional Concerns of Women (CRC Press, 2003). “About 5% have iron deficiency anemia.” Symptoms of low iron include fatigue, impaired immunity, and poor performance at school or work.
Young adults. Teen girls and young women usually need more calories than when they were younger, to support their growing and developing bodies. After about age 25, a woman’s resting metabolism (the number of calories her body needs to sustain itself at rest) goes down. To maintain a healthy weight after age 25, women need to gradually reduce their calories and increase their physical activity.
Adopting a plant-based diet could help tip the scales in your favor. A five-year study of 71,751 adults published in the Journal of the Academy of Nutrition and Dietetics found that vegetarians tend to be slimmer than meat-eaters even though both groups eat about the same number of calories daily. Researchers say it may be because carnivores consume more fatty acids and fewer weight-loss promoting nutrients, like fiber, than herbivores do. Go green to find out if it works for you.