Nickel triggers more hypersensitive reactions than any other metal – up to 15% of the population suffers from some form of nickel allergy, mostly women. Nickel is exceptionally common: in cigarettes, jewellery, buttons and in coins (including the Euro). It may be found in dental restorations, prostheses (hip, knee, cochlear and cardiac implants), colour pigments, cosmetics, stainless steel cutlery and pots. Even hard cleaning of kitchenware has been shown to release nickel in washing-up water. Nickel can pollute drinking water near factories which use it. Nutritionists have developed low-nickel diets, which cuts out certain foods (e.g. coco, chocolate, broccoli, nuts).
Please note that the information below is taken from various sources and may not reflect the situation in your country, For example, a clinic in USA states that potatoes are high in nickel, while analysis by the Swedish Food Administration found only a low nickel content in potatoes. The discrepancy is most likely due to the mineral and metal content vegetables are grown in.
The US Food and Drug Administration has issued a warning that patients who are having stents fitted should discuss metal allergy with their surgeon prior to having a stent net fitted. While nickel allergy may present as a rash or localised contact dermatitis it may also have a systemic effects including chronic fatigue and muscle pain and widespread skin conditions.
The major dietary source of nickel is plant foods. Nickel-rich food items include nuts, beans, peas, grains and chocolate. Animal foods are low in nickel. Total daily dietary intakes of nickel vary depending on the amount of plant and animal foods consumed. Diets high in plant foods, such as the ones listed above, supply about 900 micrograms daily of nickel. Nickel intake in the United States ranges from 69 to 162 micrograms daily. A daily dietary requirement of 25 to 35 micrograms has been suggested.
Nickel may be found in prepared foods (tinned foods) at markedly higher concentrations than the safe threshold laid down for hypersensitive patients. Some foodstuffs cooked in stainless-steel utensils attack the metal and thus contain much more nickel than when enamel or aluminum saucepans are used. Among the natural organic acids which may be responsible for dissolving stainless-steel, oxalic acid is the most active at equivalent concentrations.
Source: Contact Dermatitis. 1979 Jan;5(1):43-5.
Nickel in food: the role of stainless-steel utensils., Brun R.
The normal daily intake of nickel by American adults is about 0.3 to 0.6mg. About 1 to 10% of nickel in food is absorbed in the gastrointestinal tract and the remainder is excreted. The nickel content of food is partially determined by the components of the soil, in which the food was grown, pesticides used on it and the equipment used in the handling of the food. Nickel in food may vary considerably from region to region. Certain foods are routinely high in nickel content. Legumes, nuts, grains, potatoes, chocolate and fish are among the food high in nickel. In summary, ingested nickel either from food beverages or cooking utensils can cause a flare of dermatitis is some individuals. Accordingly, motivated persons may see improvement if they can reduce their ingestion of nickel through dietary changes.
|Nickel content in food|
(more than 0.5 mg/kg)
(less than 0.1 mg/kg)
|Cocoa powder||Milk chocolate||Sausage|
|Alpha alpha seeds||Garlic||Yogurt|
|Pulses (green)||Corn flour||Beetroot|
|As analysed by the Swedish Food Administration|