Your favorite health food store has plenty of supplements. But trying to figure out which nutrient is the best—decoding them—can be tricky. Here is a codebook for three widely used and important supplemental ingredients.
Vitamin: Vitamin D
What it is: Vitamin D, frequently called “the sunshine vitamin,” is synthesized by the body after exposure to sunlight. It is available in two supplemental forms, vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).
Where it comes from: Food sources of vitamin D include salmon, tuna, egg yolks, mushrooms, and fortified orange juice.
Main uses: Many people may be deficient in vitamin D, especially if they are older or work indoors. Vitamin D helps build bone density by aiding the absorption of calcium and maintaining normal blood levels of calcium and phosphorus. It also strengthens knee cartilage, protects brain cells, bolsters immune defenses, and improves mood. A clinical study found that vitamin D supplementation reduced ADHD symptoms in children, including inattention, willfulness, and impulsivity, while it improved concentration.
What to look for: Supplemental Vitamin D3 (cholecalciferol), is the active form of vitamin D synthesized by the body. Vitamin D2 (ergocalciferol) is another option, but requires conversion by the liver. Some individuals may have difficulty converting vitamin D to its active form, so D3 may be a better option.
Typical dosage level: 500 to 5,000 IU, 12.5 to 50 mcg daily
What it is: Copper is a mineral required for many processes in the body.
Where it comes from: Food sources include liver, shellfish, almonds, cashews, leafy greens, and—best of all—dark chocolate.
Main uses: Copper is crucial for blood cell formation, transporting iron in red blood cells, strengthening the immune system, and building strong bones. Copper works in tandem with other minerals, including zinc and iron. Even slight deficiencies in copper have been shown to weaken immune defenses and be a factor in anemia—generally considered a “low-iron only” problem. In fact, without copper, anemia is almost certain to follow, along with heart disease, blood sugar issues, and arthritis.
What to look for: Copper glycinate chelate forms bind copper to the amino acid glycinate, which helps the mineral absorb through the intestinal walls and into the bloodstream.
Typical dosage level: 0.5 to 1.0 mg daily
What it is: Ashwagandha (Withania somnifera) is a frequently utilized adaptogen in Ayurvedic medicine, one of the oldest healing systems in the world. The name ashwagandha comes from the Sanskrit word used to describe the smell of a horse. This not only refers to the scent of the plant’s roots after harvesting, but also to the feeling of strength and vitality those using the herb experienced.
Where it comes from: Ashwagandha is well known in India and throughout southern Asia. The plant is a small woody shrub with small yellow flowers that bloom year-round and it thrives in a sub-tropical climate.
Main uses: Powder from the roots of ashwagandha has been traditionally recommended to calm nerves, increase libido, and strengthen endurance. In clinical work, it has been shown to reduce stress-related cortisol levels, depression symptoms, and insomnia. Ashwagandha also bolsters physical stamina and exercise recovery, and boosts testosterone levels in men, but not women.
What to look for: The key compounds in ashwagandha are called withanolides, so look for a supplement that is standardized for them. Percentages of withanolides can range from 5 to 35 percent.
Typical dosage level: 125 mg to 600 mg daily