Calcium. As well as leading to osteoporosis, not getting enough calcium in your diet can also contribute to anxiety, depression, and sleep difficulties. Whatever your age or gender, it’s vital to include calcium-rich foods in your diet, limit those that deplete calcium, and get enough magnesium and vitamins D and K to help calcium do its job. Learn more »
Some people choose their cheat days to actually be cheat meals. So, one day they could have a cheat breakfast (i.e. pancakes), then a cheat lunch on another day and then a cheat dinner or dessert, and so on. While this works for some people, I found this allows me too much flexibility in my eating schedule and I start to cheat more and more because I justify it’s a cheat meal. Rather, on a cheat day, I have the whole day to get it out of my system and then move on. And it’s pretty darn glorious, let me tell you.
As continual research on the properties of supplements accumulates, databases or fact sheets for various supplements are updated regularly, including the Dietary Supplement Label Database, Dietary Supplement Ingredient Database, and Dietary Supplement Facts Sheets of the United States. In Canada where a license is issued when a supplement product has been proven by the manufacturer and government to be safe, effective and of sufficient quality for its recommended use, an eight-digit Natural Product Number is assigned and recorded in a Licensed Natural Health Products Database. The European Food Safety Authority maintains a compendium of botanical ingredients used in manufacturing of dietary supplements.
^ Siscovick DS, Barringer TA, Fretts AM, Wu JH, Lichtenstein AH, Costello RB, Kris-Etherton PM, Jacobson TA, Engler MB, Alger HM, Appel LJ, Mozaffarian D (2017). "Omega-3 Polyunsaturated Fatty Acid (Fish Oil) Supplementation and the Prevention of Clinical Cardiovascular Disease: A Science Advisory From the American Heart Association". Circulation. 135 (15): e867–e884. doi:10.1161/CIR.0000000000000482. PMID 28289069.
Make half your plate fruits and vegetables: Choose red, orange, and dark-green vegetables like tomatoes, sweet potatoes, and broccoli, along with other vegetables for your meals. Add fruit to meals as part of main or side dishes or as dessert. The more colorful you make your plate, the more likely you are to get the vitamins, minerals, and fiber your body needs to be healthy.
^ Dwyer, J. T; Wiemer, K. L; Dary, O; Keen, C. L; King, J. C; Miller, K. B; Philbert, M. A; Tarasuk, V; Taylor, C. L; Gaine, P. C; Jarvis, A. B; Bailey, R. L (2015). "Fortification and Health: Challenges and Opportunities". Advances in Nutrition: An International Review Journal. 6 (1): 124–131. doi:10.3945/an.114.007443. PMC 4288271. PMID 25593151.
A spokesperson for optimal nutritional intake is the well-known biochemist Bruce Ames, who proposed the "triage theory of nutrients," in which enzymes responsible for cell maintenance functions evolved to have lower affinity for the essential vitamin and mineral cofactors than the enzymes responsible for short-term survival, to preserve life during times of famine. 
There are thousands of dietary supplements on the market, including 40+ essential nutrients alone and in various combinations, i.e. vitamins, minerals, trace elements and fatty acids. However, a number of other nutrients are "conditionally essential", meaning that the body normally can make these molecules, but some people do not make optimal amounts. Examples are L-carnitine, alpha-lipoic acid, the methyl donor betaine,  chondroitin sulfate, coenzyme Q10, choline, amino acids such as tyrosine or arginine, and "essential" sugars normally formed in the body. 
Protein should provide about 15% of a healthy person's daily calories. As a rule of thumb, people of both sexes and any size will do fine with about 60 grams of protein a day. Athletes who have large muscles and work out hard may need 20% more. But even that's not very much; 8 ounces of chicken or 6 ounces of canned tuna, for example, will fit the bill.
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.
Keep healthy food readily available. When you get hungry, you’re more likely to eat the first thing you see on the counter or in the cupboard. Keep healthy food in easily accessible and visible places in your home and workplace. Put some fruits in a basket and place it on the kitchen counter, store healthy snacks at eye level in your pantry and stock up your fridge with small batches of cooked whole grains and fresh fruits and vegetables. At work, store quick bites like almonds, pistachios and dried berries in a jar and place it on your desk or in its top drawer.
Scientists still have much to learn even about common vitamins. One recent study found unexpected evidence about vitamin E. Earlier research suggested that men who took vitamin E supplements might have a lower risk of developing prostate cancer. “But much to our surprise, a large NIH-funded clinical trial of more than 29,000 men found that taking supplements of vitamin E actually raised—not reduced—their risk of this disease,” says Dr. Paul M. Coates, director of NIH’s Office of Dietary Supplements. That’s why it’s important to conduct clinical studies of supplements to confirm their effects.