Nickel

An average adult person contains only about 10 milligrams of nickel, which is an essential nutrient.

Nickel is built into certain important enzymes in the body. Nickel seems also involved in the production and action of some hormones.

Nickel helps iron absorption and improves bone strength.

It assists in red blood cell production, skin maintenance, and optimal growth. It also has functions in the adrenaline and glucose metabolism.

Sources

Sources of nickel are oats, peas, beans, nuts, and chocolate.

Daily intake

The recommended daily intake is 100 milligrams.

Supplementation is seldom necessary.

Deficiency

Nickel deficiency is rare.

Deficiency may be associated with low blood glucose levels, abnormal bone growth, altered metabolism of calcium, and poor absorption of iron.

Excess

Toxicity by excessive consumption is rare and would require 1000 times the amount normally consumed in food.

However, an excessive exposure from the environment, leading to toxicity, is common, e.g. from tobacco, dental implants, stainless steel kitchen utensils and inexpensive jewellery.

Overexposure to the metal is most prevalent in people involved in nickel mining or processing.

Toxicity may result in changes in glucose tolerance, blood pressure, response to stress, growth rate, bone development, and resistance to infection.

Nickel (Jewelry) Allergy

If earrings make your earlobes itch or your necklace leaves a rash around your neck, you may have a nickel allergy. It’s one of the most common skin allergies, in part because nickel is used in everything from jewelry to cell phones, coins, zippers, and eyeglass frames.

The most important thing to do is to avoid skin contact with objects having nickel in them.

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