The same protein ingredients marketed as dietary supplements can be incorporated into meal replacement and medical food products, but those are regulated and labeled differently from supplements. In the United States, "meal replacement" products are foods and are labeled as such. These typically contain protein, carbohydrates, fats, vitamins and minerals. There may be content claims such as "good source of protein", "low fat" or "lactose free." Medical foods, also nutritionally complete, are designed to be used while a person is under the care of a physician or other licensed healthcare professional. Liquid medical food products - example Ensure - are available in regular and high protein versions.
Vitamin C protects the brain and nervous system from damage caused by stress because the synthesis and maintenance of chemical neurotransmitters such as adrenaline and noradrenaline requires adequate levels of vitamin C.  Vitamin C is also needed to repair collagen which is essential for skin, blood vessels, bones and joints, and muscles. When these are damaged by physical stress, extra vitamin C is necessary. A controlled trial of 91 adults who experienced increased anxiety and stress 2-3 months after an earthquake in New Zealand in 2011 was divided into three groups, two were given a broad spectrum supplement of micronutrients in low or higher doses.  The supplements were found to alleviate the experience of stress, with the biggest dose having the biggest effect.
SOURCES: Elaine Turner, PhD, RD, associate professor, department of Food Science and Human Nutrition, University of Florida, Gainesville. Sharon B. Spalding, MEd, CSCS, professor, physical education and health; and associate director, Virginia Women's Institute for Leadership, Mary Baldwin College Staunton, Va. American Dietetic Association web site. Institute of Medicine at the National Academies web site.
A person's caloric requirement depends on his body size and exercise level. Sedentary people of both genders will keep their weight stable by taking in about 13 calories per pound of body weight each day. Moderate physical activity boosts this requirement to 16 calories a pound, and vigorous exercise calls for about 18 calories a pound. On average, a moderately active 125-pound woman needs 2,000 calories a day; a 175-pound guy with a similar exercise pattern needs 2,800 calories. And like women, men will lose weight only if they burn more calories than they take in.
Considering average dietary needs and the prevalence of certain health conditions, some basic guidelines may provide the foundation for the effective use of nutritional supplements. First, a high quality, broad-spectrum multivitamin and mineral supplement, taken once per day, is recommended to provide a range of nutrients. This should contain the B-complex vitamins B6, B12, and folic acid, which may help prevent heart disease, and the minerals zinc and copper, which aid immunity. In addition to a multivitamin, antioxidants can be added to a supplementation routine. These include vitamin A (or beta-carotene), vitamin C, and vitamin E, and the mineral selenium. Antioxidants may have several positive effects on the body, such as slowing the aging process, reducing the risks of cancer and heart disease, and reducing the risks of illness and infection by supporting the immune system. Coenzyme Q10 is another antioxidant in wide usage, as studies have shown it may improve the health of the heart and reduce the effects of heart disease. Essential fatty acids, particularly omega-3, are also recommended as they are involved in many important processes in the body, including brain function. Calcium supplementation is recommended for the elderly and for women, to strengthen bones and prevent bone loss. Calcium supplements that are balanced with magnesium have a less constipating effect and are better absorbed.
A 2013 study on herbal supplements found that many products were of low quality, one third did not contain the active ingredient(s) claimed, and one third contained unlisted substances. In a genetic analysis of herbal supplements, 78% of samples contained animal DNA that was not identified as an ingredient on the product labels. In some botanical products, undeclared ingredients were used to increase the bulk of the product and reduce its cost of manufacturing, while potentially violating certain religious and/or cultural limitations on consuming animal ingredients, such as cow, buffalo or deer. In 2015, the New York Attorney General identified four major retailers with dietary supplement products that contained fraudulent and potentially dangerous ingredients, requiring the companies to remove the products from retail stores.
The easiest way to make sure your inter-meal nibbling stays on track is to have healthy snacks on hand for when hunger strikes. You can keep these nonperishable goodies in your desk drawers, or these energy-boosting nibbles in your gym bag. Simply keeping a bowl of fresh fruit on your kitchen counter will bring your snacking to the next healthy level.
"Studies show that omega-3 fatty acids are cardio-protective and the basis for the AHA recommendation to consume fatty fish twice weekly," she says. "But the studies do not show that popping a supplement can have the same benefit in healthy individuals." She adds, "There is also a misperception that fish oils can lower cholesterol, but this is not true."
Make half the grains you eat whole grains: An easy way to eat more whole grains is to switch from a refined-grain food to a whole-grain food. For example, eat whole-wheat bread instead of white bread. Read the ingredients list and choose products that list a whole-grain ingredients first. Look for things like: "whole wheat," "brown rice," "bulgur," "buckwheat," "oatmeal," "rolled oats," quinoa," or "wild rice."
The average American diet leaves a lot to be desired. Research finds our plates lacking in a number of essential nutrients, including calcium, potassium, magnesium, and vitamins A, C, and D. It's no wonder that more than half of us open a supplement bottle to get the nutrition we need. Many of us take supplements not just to make up for what we're missing, but also because we hope to give ourselves an extra health boost—a preventive buffer to ward off disease.
The U.S. Public Health Service recommends that all women of childbearing age consume 400 mcg of folic acid (a B vitamin) daily to reduce their risk of having a pregnancy affected with spina bifida or other neural-tube defects. Women who are actively trying to get pregnant should consume 600 mcg, and lactating women should consumer 500 mcg. Women of childbearing age should also take care to meet the daily requirements for calcium, fiber, iron, protein and vitamin D. Discuss supplements with a health care professional, however. Iron and vitamin D in particular can be dangerous in high amounts.
You don't have to hunt and skin your supper, but if your chicken has been molded into a nugget, who knows what you're really chewing. And when you choose meat that's been processed into sausage, strips or slices, you're downing sodium and preservatives instead of healthy nutrients, says Adam Drewnowski, Ph.D., director of the nutritional sciences program at the University of Washington at Seattle. Stick to unfussed-with cuts straight from the butcher.
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.
Use MyPlate (PDF – 281 KB) as a guide to build a healthy diet. Think about filling your plate with foods from the five food groups — fruits, vegetables, grains, proteins, and dairy — at each meal. Snacks can be a good way to fill in fruits and whole grains you might have missed at meals. Most of us don’t need complicated calorie counting programs or special recipes for healthy eating.
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.