The Role of Vitamin C in Copper and Iron Absorption

Iron-Copper-Absorption-LivOn-Labs

According to the World Health Organization (WHO), iron deficiency is considered the most common and widespread nutritional issue in the world. More iron is absorbed when iron stores are low, while less is absorbed if the body’s stores are appropriate. Dietary iron is in the form of either heme iron or nonheme iron. Although the iron found in meat (heme iron) is easily absorbed, the iron in plant-based foods and eggs (non-heme iron) is absorbed differently, as it  depends on the presence of other nutrients.

The non-heme iron in vegetables, egg yolks, fruits, grains, iron-fortified products, nuts, and seeds is absorbed less efficiently than the heme iron found in poultry, fish, and meat. Fortunately, Vitamin C assists the body in absorbing more non-heme iron from these sources, thereby improving the body’s ability to utilize more iron from these sources than it could otherwise. Vitamin C can also help overcome some of the negative effects of phytonutrients such as phytic acid, tannins, polyphenols, and oxalic acid, which can interfere with non-heme iron absorption. Vitamin C can be obtained from supplements or from dietary sources such as broccoli, oranges, kiwi, tomatoes, bell peppers, mangoes, and strawberries.

Copper is essential to several processes within the body, including iron metabolism.  There are four copper-containing enzymes – called multi-copper oxidases (MCO) – that can change ferrous iron to ferric iron, the form or iron needed for red blood cell formation.  These enzymes make up the ceruloplasmin levels in the body.

Although Vitamin C supplements have been found to contribute to copper deficiency in animals, Vitamin C’s effect on the nutritional status of copper in humans is still being studied. Two minor studies on healthy young men indicated the oxidase activity of ceruloplasmin may be lowered by higher doses of Vitamin C supplements. One of the studies found that a total of 1,500mg of Vitamin C taken each day for two months resulted in lower ceruloplasmin activity. The other study indicated that 605 mg of Vitamin C supplements per day for 3 weeks created a decline in ceruloplasmin oxidase activity but did not cause copper absorption to decline. Neither of the studies determined supplementing with Vitamin C negatively affects copper nutritional status.

  1. Hickey S., Roberts H, Miller N, (2008), “Pharmacokinetics of oral vitamin C” Journal of Nutritional & Environmental Medicine July 31.