Trace minerals are often overlooked and forgotten about since they are only needed in such small quantities in the body. But these underappreciated minerals do a lot for our health and keep us functioning every day. Trace minerals can be supplemented through a daily multivitamin or individually based on what the body may need. However, not all supplements are created equal. So how do you know which supplement to buy? Some forms of minerals are more bioavailable than others, meaning they can be absorbed easier in the body. Typically, minerals that are chelated or attached to an amino acid are considered to be the most bioavailable because they prevent the nutrient from interacting with other compounds in the absorption process. We have compiled a list of the most bioavailable forms of trace minerals to make it easier for you to shop for your supplements.
Highlighted in color are the most bioavailable supplemental forms of each mineral and these are the words you may want to look for on the nutrition label when shopping for supplements.
- Chromium: Not much is known about chromium and its function in the body but it has been proposed to be one of the body’s ways of controlling blood sugar and potentially playing a role in discouraging sugar cravings and diabetes. Of the various forms of chromium present in supplements, one study showed that between chromium nicotinate and chromium picolinate, chromium nicotinate was more effective in reducing inflammation and lipid levels in diabetic rats suggesting that it may be more bioavailable. Another study shows chromium dinicocysteinate as being successful in decreasing insulin resistance in diabetic patients. Based on the research, a chelated form of chromium may be the most bioavailable supplement. Look on the nutrition label for chromium nicotinate glycinate chelate when shopping for a supplement.
- Copper: Copper is essential for maintaining healthy oxygen in the blood which provides energy to the body. The tricky part of copper supplementation is that too much can cause a zinc deficiency and too much zinc can cause a copper deficiency so a perfect balance of zinc and copper must be achieved. In fact, excess copper has been linked to Alzheimer’s disease and schizophrenia. Because of the potential adverse effects of excess copper, supplementation is not often recommended and instead, copper should be acquired through foods such as beans, whole wheat grains, prunes, organ meats, and seafood. However, if supplementation is desired, a chelated copper supplement may be most bioavailable as these types of supplements are generally absorbed better. Look on the nutrition label for copper glycinate, the most popular chelated supplement form.
- Iodine: Nearly all of the body’s iodine is present in the thyroid gland where it works to control metabolism, influence weight gain, and affect the speed of mental reactions. Most salt in developed countries is now iodized so iodine deficiency is uncommon yet it can still occur since some salts lack iodine including those marketed as “himalayan” or “kosher”. Iodine is commonly present in two supplement forms: potassium iodide and sodium iodide. Of the two, potassium iodide has been shown to be almost entirely (94.6%) absorbed by the body and is therefore, the preferred supplement form with the highest bioavailability. Iodine can also be obtained naturally through kelp supplements. When shopping for iodine supplements look for kelp (natural iodine) or potassium iodide.
- Iron: Iron, although a trace mineral, is extremely important for life because of its contributing role to the formation of red blood cells which provides the oxygen that is transported throughout the body. There are two types of iron: heme and nonheme iron. Heme iron comes from animal products and has a higher bioavailability than nonheme iron which is from plant products. Because the most absorbable form of iron is from animal products, vegetarians and vegans are at risk for iron deficiency as well as women who have heavy menstrual bleeding. Most iron supplements are in the nonheme form which means they are vegetarian friendly but there are some heme iron supplements on the market that would be most effective. Nonheme iron supplements include ferrous and ferric salt forms, the former being more soluble and bioavailable. The best ferrous iron supplement is ferrous fumarate because it has the greatest elemental iron content and it does not destroy vitamin E like ferrous sulfate does. There are also chelated iron supplements available such as ferrous bisglycinate that have been shown to have comparable bioavailability to ferrous fumarate. When looking for a nonheme iron supplement, search on the nutrition label for either ferrous fumarate or ferrous bisglycinate and when looking for a heme iron supplement, it will be sourced from bovine (beef) liver. It should be noted that if you take your supplements in the morning, you may want to avoid drinking coffee or tea because they interfere with the absorption of iron. It is also notable that copper, manganese, cobalt, and vitamin C are required for iron absorption so a multivitamin or iron-complex supplement may be better for achieving a higher bioavailability.
- Manganese: Manganese is an underrated mineral that functions in nearly every body system from helping maintain bone structure to regulating hormones to even boosting memory and eliminating fatigue. There is currently little to no conclusive evidence on the bioavailability of the various forms of manganese supplements. However, based on evidence from other trace minerals, it may be safe to assume that a chelated manganese supplement is the most bioavailable form. Chelated manganese supplements include manganese aspartate and manganese glycinate or bisglycinate.
- Molybdenum: Molybdenum is involved in fat and carbohydrate metabolism as well the removal of drugs and other toxic substances that enter the body. Molybdenum is most likely unnecessary to supplement especially if a daily multivitamin is taken and a wholesome diet is consumed. However, of the various molybdenum supplements on the market, an amino acid chelate may provide the most bioavailability as it is highly stable throughout the absorption process. The most common chelated form of molybdenum is molybdenum glycinate.
- Selenium: Selenium is an antioxidant that works synergistically with vitamin E to slow down aging and protect the body against oxidative damage as well as certain cancers. Selenium deficiency is rare but can still occur, more so in men who require a higher amount of selenium than women for reproductive function. The most bioavailable supplement form is selenomethionine with 90% of selenium being absorbed in the body. When shopping for a selenium supplement, look on the nutrition label for selenomethionine with vitamin E.
- Zinc: Recently, zinc has gained some attention for fighting off colds and illnesses including COVID-19, but zinc also has many other roles in the body by contributing to enzymes and metabolic processes. Zinc comes in many supplemental forms but which one is best? Zinc oxide and zinc sulfate are two common inorganic zinc supplements that are often cheaper, however, they do not provide the same bioavailability that organic forms of zinc give such as zinc gluconate and zinc glycinate. Between the organic zinc forms, zinc bis-glycinate was shown to be superior to zinc gluconate. In order for zinc to reduce the duration of cold symptoms, a lozenge form that dissolves in the mouth must be taken or else the supplementation will be ineffective. When looking for a zinc supplement, search on the nutrition label for zinc bisglycinate or a zinc lozenge.
