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Nickel in food: the low-nickel diet and who it is actually for

Nickel is the classic contact allergen — jewellery, belt buckles, phone cases — and by a wide margin the most common one found on patch testing in Europe. A much smaller group of people who are sensitised also react to the nickel they eat, and that is what a low-nickel diet is for.

Not a diagnosis. Nickel allergy is confirmed by patch testing performed by a dermatology service, and a low-nickel diet only makes sense after that confirmation and under supervision — it restricts legumes, wholegrains and nuts, which are foods worth keeping. Widespread or worsening dermatitis needs a clinician, not a food list.

Contact allergy first, diet a long way second

Nickel contact allergy is common — surveys across European populations consistently find it as the leading positive on patch testing, and much more often in women than in men, historically because of ear piercing and jewellery. The EU responded with a restriction under chemicals law that limits how much nickel may be released from articles in prolonged contact with the skin, with a tighter limit for posts inserted into pierced ears, and that restriction measurably reduced sensitisation in younger cohorts.

Systemic nickel allergy syndrome is the much less common step beyond that: a person already sensitised by skin contact develops dermatitis — often on the hands, or in a widespread pattern — and sometimes digestive symptoms, in response to nickel absorbed from food. It is a real phenomenon, but it applies to a minority of nickel-allergic people, and the studies supporting dietary treatment are small.

The order of operations therefore matters. Patch testing confirms sensitisation. Removing the metal sources in contact with skin comes next, because that is where most of the exposure is. Only then does dietary nickel become a sensible thing to investigate, and it should be a defined trial with a defined end.

Where dietary nickel comes from

Plants take nickel up from soil, and the concentration varies with the soil as much as with the species — which is why nickel tables from different countries disagree, and why no table can tell you what is in the lentils you bought. What holds across all of them is the ranking: legumes, especially soy, and wholegrain cereals, nuts, seeds and cocoa sit at the top, while meat, fish, eggs, dairy, refined grains and most fruit sit far below.

A significant part of the exposure never came from a plant at all. Nickel leaches out of stainless steel cookware, and it does so much more when the food is acidic, when the pan is new, and when cooking is long. It also concentrates in canned food, and it accumulates in water that has stood overnight in the plumbing — which is why running the tap for a while before drawing drinking water is standard advice for anyone on a low-nickel diet.

What the safety assessments say

Nickel in food is assessed as a contaminant, not a nutrient. The European Food Safety Authority re-assessed it and derived a tolerable daily intake for the long-term effects, and separately addressed the acute problem — the eczematous flare-up that occurs in already-sensitised people after an oral dose — which needs a short-term reference value rather than a lifetime average. The point of having two values is that the two effects behave differently: one is a chronic toxicological endpoint, the other a same-day immunological one in a susceptible subgroup.

The published figures belong with the opinion they came from, so they are not reproduced here; the assessment is on the EFSA site and is the document to read if you want the numbers.

For practical purposes the useful conclusion is the shape of the problem rather than the number: ordinary diets are not a toxicological concern, and the dietary question is entirely about the sensitised minority.

Nickeltoidugrupi järgi

Ribad, mitte kümnendid. Kus avaldatud kogust konkreetse toidu jaoks ei saanud dokumendi vastu kontrollida, trükib see pind riba, mitte arvu — ja iga toit allpool lingib oma toitumislehele, et näha, mis veel selles on.

Mis numbrit muudab

• Soil is the biggest variable in the plant itself — the same crop from two regions can differ substantially.
• Acidic cooking in stainless steel adds nickel to the dish; enamelled or glass cookware does not.
• New pans leach more than old ones, and the rate falls with use.
• Canning adds nickel; the same food fresh or frozen carries less.
• Running the tap before drawing water clears the metal that leached into standing plumbing.

Kus mujal need toidud on märgitud

Toidud, mis on sellel lehel tõstetud ja istuvad ka tõstetud ribas vähemalt kahel teisel viieteistkümnest. Rahustavaid ribasid ei loeta, nii et rida siin tähendab, et toit kogub tõeliselt märgiseid, mitte et teda lihtsalt palju mainitakse.

Tasub lugeda enne millegi eemaldamist. Selle pinna nimekirjad kirjutati igaüks teisele inimesele teise probleemiga, ja nad koonduvad samale väikesele toitainerikka toidu grupile. Kõigi rahuldamine korraga toodab dieedi, mida keegi ei kavandanud ja keegi pole testinud.

Rääkimine kellegagi, kes tegelikult saab testida

Nothing on this surface is personal medical advice. If a food genuinely makes you ill, if you have had a kidney stone or a gout attack, or if you are considering removing a food group from your diet, the person to talk to is your doctor, pharmacist or a registered dietitian — they can test for the things that can be tested for, which a table cannot.

Allikad:European Food Safety Authority — scientific opinion on nickel in food and drinking water, including the separate treatment of chronic and acute effects. · EU restriction on nickel release from articles in prolonged contact with the skin, under the REACH chemicals regulation. · European surveillance of contact allergy, which consistently ranks nickel first on patch testing.· Toidunimed ja lingid: saidi toidubaas. Kontrollitud2026-09-06.

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