Even if you are the most independent exerciser around, give a group fitness class a shot at least once a week—you may find that you enjoy it more than sweating solo. “Happiness and health are shared through social connectedness and closeness,” says Greg Chertok, director of sport psychology at the Physical Medicine and Rehabilitation Center in New Jersey. “Geography and proximity are predictors of how contagious emotions can be, and this may translate into an athletic environment too.” Sign up for Bikram, CrossFit, spin, or Zumba, and you could find yourself—gasp!—smiling at the gym thanks to your classmates.
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.
You can get calcium from dairy products like milk, yogurt and cheese, canned fish with soft bones (sardines, anchovies and salmon; bones must be consumed to get the benefit of calcium), dark-green leafy vegetables (such as kale, mustard greens and turnip greens) and even tofu (if it's processed with calcium sulfate). Some foods are calcium-fortified; that is, they contain additional calcium. Examples include orange juice, certain cereals, soy milk and other breakfast foods. Talk to your health care professional about whether you should take calcium supplements if you don't think you're getting enough calcium from food sources.
Calcium: Although some bone loss is inevitable with age, women can slow the process by getting enough calcium and vitamin D. Women between the ages of 50 and 70 need 1200 mg of calcium and 600 IU of Vitamin D a day. Women older than 70 require 1200 mg of calcium and 800 IU of Vitamin D a day. Because the skin becomes less efficient at converting sunlight to vitamin D as we age, older women may need more vitamin D in the form of supplements. Talk to your doctor.
Calcium may even be harmful for men, at least in large amounts. The worry is prostate cancer, and two Harvard studies have raised the alarm. In 1998, the Health Professionals Follow-up Study found that a high consumption of calcium from food or supplements was linked to an increased risk of advanced prostate cancer. The risk was greatest in men who got more than 2,000 mg a day. More recently, the U.S. Physicians' Health Study reported that a high consumption of calcium from dairy products appeared to increase a man's risk of prostate cancer by up to 37%. A study from the Fred Hutchinson Cancer Research Center in Seattle also found a link between calcium and advanced prostate cancer.
Always be sure you get regular servings of dairy products, calcium-rich tofu and greens, and calcium-fortified orange juice. Also, eat lean meat and/or high-quality protein combinations such as pinto beans and rice. Avoid fiber supplements as these bind calcium and other minerals in the intestinal tract. When this happens the absorption of essential nutrients decreases.
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.