Examples of ongoing government research organizations to better understand the potential health properties and safety of dietary supplements are the European Food Safety Authority, the Office of Dietary Supplements of the United States National Institutes of Health, the Natural and Non-prescription Health Products Directorate of Canada, and the Therapeutic Goods Administration of Australia. Together with public and private research groups, these agencies construct databases on supplement properties, perform research on quality, safety, and population trends of supplement use, and evaluate the potential clinical efficacy of supplements for maintaining health or lowering disease risk.
Magkos, F., Fraterrigo, G., Yoshino, J., Luecking, C., Kirbach, K., Kelly, S. C., … Klein, S. (2016, April 12). Effects of moderate and subsequent progressive weight loss on metabolic function and adipose tissue biology in humans with obesity. Cell Metabolism, 23(4), 591–601. Retrieved from https://www.sciencedirect.com/science/article/pii/S1550413116300535
An important take-home message is to focus on the types of foods you eat and your overall dietary pattern, instead of on individual nutrients such as fat, dietary cholesterol, or specific vitamins. There are no single nutrients or vitamins that can make you healthy. Instead, there is a short list of key food types that together can dramatically reduce your risk for heart disease.
Nutritional supplements are used for many purposes. They can be added to the diet to boost overall health and energy; to provide immune system support and reduce the risks of illness and age-related conditions; to improve performance in athletic and mental activities; and to support the healing process during illness and disease. However, most of these products are treated as food and not regulated as drugs are.
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.
Good sources of iron include liver, kidneys, red meat, poultry, eggs, peas, legumes, dried fruits and dark, green leafy vegetables. Three ounces of cooked chicken liver contains 7.2 mg of iron; a cup of cooked spinach contains 6.4 mg. Your health care professional will probably recommend iron supplements during pregnancy (probably starting at 30 mg per day).
Nutritional supplements may be designed to provide specialized support for athletes. Some of these consist of high-protein products, such as amino acid supplements, while other products contain nutrients that support metabolism, energy, and athletic performance and recovery. People engaging in intense athletic activity may have increased needs for water-soluble vitamins, antioxidants, and certain minerals, including chromium. Sports drinks contain blends of electrolytes (salts) that the body loses during exertion and sweating, as well as vitamins, minerals, and performance-supporting herbs.