Trace Minerals

Getting trace minerals into foods and beverages has become easier with the perfection of micro- and nanoencapsulation techniques.

Some trace minerals, for example selenium, have developed a reputation for their healthful antioxidant benefits. "Selenium, especially in the organic form selenomethionine, is one of the most versatile antioxidants," says Vladimir Badmaev, MD, vice president medical and scientific affairs, Sabinsa Corp., Piscataway, N.J.

Selenium is an essential trace element for the prevention of disease in humans. "Studies indicate an association between low nutritional selenium status and increased risks of cardiomyopathy, cardiovascular disease and carcinogenesis in various sites of the body," Badmaev explains.

Vying for attention

Chromium is essential to efficient sugar metabolism. It is believed to enhance the effects of insulin in helping cells pull glucose from the blood. It is believed both endurance exercise, which causes a loss of chromium, and a diet rich in simple sugars, may increase the need for chromium.

There is no RDA for chromium, but an adequate intake (AI) is set at 30 mcg per day for men and 20 for women (40 mcg for women who are breast-feeding). The most abundant food-borne sources of chromium are whole grains, broccoli and green beans, but the database is far from complete.

"Good chromium food sources (also) include lean meats, cheeses and some condiments, such as black pepper and thyme," says Mark Fanion, communications manager, Fortitech Inc. Schenectady, N.Y. "Brewer's yeast also is rich in chromium." Fanion notes applications ideal for chromium fortification include whole-grain breads and cereals and cheese products.

Penny for Your Thoughts

Copper is vital to the function of many enzymes known as cuproenzymes. One of these, cytochrome-c oxidase, catalyzes the reduction of oxygen to water. This step is critical to the production of ATP, the cell's energy currency.

Because energy production can generate reactive oxygen species, the cell maintains antioxidant protection in the form of enzymes like copper and zinc-containing superoxide dismutase (CuZn-SOD), found throughout each cell. A deficiency in copper can at once compromise our energy and the body's defense against reactive oxygen species.

There are two forms of SOD that contain copper: copper/zinc SOD in most cells, including red blood cells and extracellular SOD found in high levels in the lungs. Adequate copper is necessary for normal iron metabolism and red blood cell formation.

Copper is also important for building collagen and elastin, essential components of connective tissue, especially in the heart, blood vessels and bones. Cuproenzymes are essential to normal central nervous system and brain functions. The RDA for copper is set at 1 mg per day.

Manganese is a versatile trace mineral that acts as an essential cofactor for several different enzymes, allowing it to take on metabolic tasks ranging from gluconeogenesis (creating glucose) to the metabolism of carbohydrates and protein.

Manganese, too, is needed for healthy collagen and critical to skeletal integrity and efficient wound repair. Another form of SOD, manganese superoxide dismutase (MnSOD), a primary enzyme against reactive oxygen species. Our need for manganese is estimated to be 2 mg per day.

Trace but not Trivial

The pound-for-pound punch of copper and manganese is impressive, but less than half as much molybdenum goes pretty far. The RDA for this essential trace element weighs in at a mere 45 mcg per day. While scarce in the environment, it is vital for virtually all forms of life.

The most important of these enzymes to human nutrition is xanthine oxidase, which catalizes the breakdown of nucleotides into uric acid, and increases the antioxidant capacity of the blood. This critical enzyme may also aid in detoxification of drugs and foreign substances. "Some good food sources of molybdenum include whole grains, organ meats, leafy green vegetables, legumes, and beans," says Fanion. The availability of molybdenum varies widely because of variations in the molybdenum content of soil. Vegetables grown in molybdenum-rich soil may contain up to 500 times more molybdenum than those grown in molybdenum-deficient soils.

There is clinical uncertainty about the need for Vanadium in human nutrition, but the latest research indicates it may strongly influence glucose metabolism. In studies, persons with type 2 diabetes given vanadium show significantly reduced blood glucose levels. Changes in various enzymes levels related to glucose suggest the glucose was stored as glycogen.

Trace minerals are found in a wide variety of foods depending in their distribution in the environment. But they are elements, and so cannot be made by the plants. If the soil is deficient, the plants are deficient, along with all of the animals up the food chain.

"Based on statistical data, the American diet supplies adequate levels of selenium," says Sabinsa's Badmaev. "However, the issue of selenium nutritional status in this country is complexed by several factors, such as environmental selenium status. For example, it has also been postulated that the unusually high mortality rate from cardiovascular disease in southeastern Georgia may be due to selenium deficiency in the soil and water."

For now, most products taking advantage of trace minerals as value-added ingredients are sports/energy bars and drinks. Examples can be found in Kraft Foods Inc.'s Balance Nutrition bars; Berkeley, Calif.-based PowerBar's Pria Nutrition bars and beverage system drinks; and Odwalla Inc., Half Moon Bay, Calif.'s Odwalla bars.

Getting trace minerals into foods and beverages has become easier with the perfection of micro- and nanoencapsulation techniques. But some issues merit consideration. First is flavor impact, since even the miniscule amounts needed can alter taste. Also, deficiencies are rare. Still, there are certain benefits to employing trace minerals in products specifically marketed as being sources of a more complete mineral spectrum.