Poor nutrition can manifest itself in many ways. The more obvious symptoms of a nutritional deficiency include dull, dry or shedding hair; red, dry, pale or dull eyes; spoon-shaped, brittle or ridged nails; bleeding gums; swollen, red, cracked lips; flaky skin that doesn't heal quickly; swelling in your legs and feet; wasted, weak muscles; memory loss; and fatigue.
If you do decide to diet, you still need to maintain good nutrition. You want to cut back on calories, not nutrients. And while you want to reduce fat, don't eliminate it entirely. Some studies suggest that older women who maintain a higher body-fat percentage are less likely to suffer from osteoporosis and other conditions associated with menopause. Fat cells also retain estrogen, which helps maintain the calcium in your bones. Younger women should be careful, too: a low body fat percentage can lead to infertility; below 17 percent may lead to missed periods, also known as amenorrhea.
Animal products, such as meat, fish and poultry are good and important sources of iron. Iron from plant sources are found in peas and beans, spinach and other green leafy vegetables, potatoes, and whole-grain and iron-fortified cereal products. The addition of even relatively small amounts of meat or foods containing vitamin C substantially increases the total amount of iron absorbed from the entire meal.

There were also supplementation programs that targeted nonpregnant women. National supplementation programs that provided food baskets to low-income families increased maternal BMI and improved household food insecurity (92, 93). However, there were some unintended consequences. In Mexico, food transfer programs disproportionately increased weight gain in overweight women compared with underweight women (93), and 1 study in Bangladesh found that food transfers had larger impacts on men's intake than women's intake, except with less preferred foods (94). Adolescents who received protein-energy supplementation at school showed an increase in weight gain during supplementation, as well as improvements in school attendance and mathematics scores (46, 95). However, the impact of supplementation on micronutrient deficiencies and, specifically, hemoglobin concentration, was limited (46).
Changes in the way research ethics was visualised in the wake of the Nuremberg Trials (1946), led to an atmosphere of protectionism of groups deemed to be vulnerable that was often legislated or regulated. This resulted in the relative underrepresentation of women in clinical trials. The position of women in research was further compromised in 1977, when in response to the tragedies resulting from thalidomide and diethylstilbestrol (DES), the United States Food and Drug Administration (FDA) prohibited women of child-bearing years from participation in early stage clinical trials. In practice this ban was often applied very widely to exclude all women.[151][152] Women, at least those in the child-bearing years, were also deemed unsuitable research subjects due to their fluctuating hormonal levels during the menstrual cycle. However, research has demonstrated significant biological differences between the sexes in rates of susceptibility, symptoms and response to treatment in many major areas of health, including heart disease and some cancers. These exclusions pose a threat to the application of evidence-based medicine to women, and compromise to care offered to both women and men.[6][153]