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.
Omega-3s: These essential fatty acids, EPA and DHA, play many roles in the body, including building healthy brain and nerve cells. Some studies show that omega-3s, especially DHA, can help prevent preterm births. Even women who don't plan to have children should be sure to get plenty of omega-3s. These healthy oils have been shown to reduce the risk of heart disease, the number one killer of women.
Healthy eating is a way of eating that improves your health and helps prevent disease. It means choosing different types of healthy food from all of the food groups (fruits, vegetables, grains, dairy, and proteins), most of the time, in the correct amounts for you. Healthy eating also means not eating a lot of foods with added sugar, sodium (salt), and saturated and trans fats.
Actually, more people suffer from food intolerances, which don't involve the immune system. However, food intolerance symptoms—such as intestinal distress—may mimic those of a food allergy. If you have a food intolerance, talk to a nutritionist about diagnosis and treatment; if you have food allergies, you need to see an allergist. Whether you have food allergies or intolerance, you will need to develop a diet that fits your needs and avoids foods that trigger a reaction.
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.
However, 30% is still a lot of fat for one serving, so considered absolute values like how many grams of fat, carbohydrates, protein, etc. are consumed instead of relative values like "50% less fat." Additionally, reaching fitness goals is largely about calorie intake. More body fat and unwanted weight will be gained by eating 500 calories of a low-fat item than by eating 100 calories of a high-fat item, so keep this in mind.