Protein-containing supplements, either ready-to-drink or as powders to be mixed into water, are marketed as aids to people recovering from illness or injury, those hoping to thwart the sarcopenia of old age, to athletes who believe that strenuous physical activity increases protein requirements, to people hoping to lose weight while minimizing muscle loss, i.e., conducting a protein-sparing modified fast, and to people who want to increase muscle size for performance and appearance. Whey protein is a popular ingredient, but products may also incorporate casein, soy, pea, hemp or rice protein.
(OMNS Sept 12 2018) One of the most vitamin-restrictive countries in the world is Norway. There, authorities limit potencies to only slightly higher than RDA (Recommended Dietary Allowance) levels for dietary supplements sold outside of pharmacies. The traditional reasoning is that most people receive the nutrients they need from a "balanced diet."  The authorities are also obsessively concerned that some vitamins and minerals are harmful in high doses. And, since an intake of water-soluble vitamins in excess of needs is excreted in the urine, Norwegian "experts" advise that taking supplements is a waste of money. Accordingly, the argument goes, the public should be protected not only from possible harm, but also from wasting money on unnecessary nutrients. The official policies on nutritional supplements vary within OECD (Organization for Economic Cooperation and Development) countries. Some are more liberal, while others are even more restrictive.
To assure supplements have sufficient quality, standardization, and safety for public consumption, research efforts have focused on development of reference materials for supplement manufacturing and monitoring. High-dose products have received research attention, especially for emergency situations such as vitamin A deficiency in malnutrition of children, and for women taking folate supplements to reduce the risk of breast cancer.
If you lose weight suddenly or for unknown reasons, talk to your health care professional immediately. Unexplained weight loss may indicate a serious health condition. And even if it doesn't, simply being underweight is linked to menstrual irregularity, menstrual cessation (and sometimes, as a result, dental problems, such as erosion of the enamel and osteoporosis) and a higher risk of early death.
Women need more of this mineral because they lose an average of 15 to 20 milligrams of iron each month during menstruation. Without enough iron, iron deficiency anemia can develop and cause symptoms that include fatigue and headaches. After menopause, body iron generally increases. Therefore, iron deficiency in women older than 50 years of age may indicate blood loss from another source and should be checked by a physician.
For example, while increased consumption of fruits and vegetables are related to decreases in mortality, cardiovascular diseases and cancers, supplementation with key factors found in fruits and vegetable, like antioxidants, vitamins, or minerals, do not help and some have been found to be harmful in some cases. In general as of 2016, robust clinical data is lacking, that shows that any kind of dietary supplementation does more good than harm for people who are healthy and eating a reasonable diet but there is clear data showing that dietary pattern and lifestyle choices are associated with health outcomes.