Other and nickel: 82 foods rated

Chocolate is high in nickel through its cocoa, and the figure moves with the cocoa percentage rather than with the brand. Reading the percentage tells you more here than reading the name. Flyvholm's review is where that ranking comes from: cocoa and chocolate sit among the very high contents, with soya beans, oatmeal, nuts and legumes. It publishes no figure for any single food, which is why this is a rank and not a milligram — and it puts average Danish dietary nickel at 150 micrograms a day, rising past 900 where the high items are eaten in quantity.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Cocoa mass is the whole ground bean, fat included, and carries the cacao tree's full nickel load. It is the ingredient that decides the level of every chocolate it goes into. The second French Total Diet Study puts dark chocolate among the food groups highest in nickel — a ranking of groups rather than a figure for the ingredient.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Cocoa nibs are the bean broken up and nothing else - no sugar to dilute the nickel, no milk. Weight for weight they are the highest form in which cocoa is eaten directly.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Cocoa powder is among the highest-nickel foods measured anywhere - the cacao tree accumulates the metal from the soil, and removing the fat concentrates what is left. It is the most concentrated form of the whole cocoa family.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Coconut butter is ground coconut flesh - the whole thing, fat and fibre together, the way a nut butter is the whole nut. Nothing was separated, so nothing was left behind, and the nickel that puts coconut high on this axis is still in the jar. Only the OIL escapes it, because pressing is the one process here that actually divides the flesh in two.

• Ahmed M et al., J Food Compos Anal 2024, essential and non-essential metals in coconut milk
• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984)

Dairy-free chocolate is high for the reason all chocolate is - the cocoa - and removing the milk removes none of it. These bars often raise the cocoa percentage to compensate for texture, which raises the nickel with it.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Dark chocolate is high because the level tracks cocoa content: the higher the percentage, the more nickel. An 85% bar carries roughly twice what a 45% one does.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Fermented tofu is tofu that has been cured further, so it starts from the highest-nickel food group measured and loses nothing on the way. It is eaten in small cubes, which is the only thing keeping the dose down.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Hazelnut spread puts two of the foods named as very high in nickel, hazelnut and cocoa, in the same jar. There is no version of it that is not high.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Natto is whole fermented soybeans, eaten by the beanful. Its nickel is the bean's, untouched by the fermentation - which is worth saying, because natto is often chosen precisely for what fermentation does to everything else in it.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Tempeh is the whole soybean, fermented and pressed - nothing is removed, so the bean's nickel is all still there. Fermentation changes the carbohydrates and the amines; it cannot change a metal.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Tofu was the single highest-nickel food group in the French Total Diet Study - above shellfish, above dark chocolate. Pressing soy milk into a block concentrates what the bean took up, and tofu is eaten as a main portion rather than a garnish.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake
• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Almond butter is the whole nut ground to a paste - nothing removed, nothing added. It spreads thinly, which is the only reason its nickel sits below the almonds' own.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake

Almond cream is almonds and sugar, and the sugar dilutes the nickel without removing any. It goes into fillings and pastries in generous amounts, so the portion is rarely small.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake

Almond yogurt is fermented almond drink, thicker than the drink and eaten by the pot. Fermentation changes the sugars and the texture; it leaves the nickel exactly where it was.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake

Cashew cheese is blended cashews with cultures and salt - a concentrated nut preparation wearing the name of a dairy product. It carries the cashew's nickel, and it is eaten in cheese-sized portions rather than nut-sized ones.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake

Chocolate chips carry the cocoa's nickel, but they are scattered rather than eaten as a bar. A handful in a cookie dough is a different dose from the tablet the same chocolate would have made.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Coconut yogurt is coconut milk fermented - the flesh, extracted into water, then cultured. Diluted, then, but not purified: the nickel that puts coconut high on this axis is still there, at a lower concentration than the flesh. Fermentation acts on sugars, not on metals.

• Ahmed M et al., J Food Compos Anal 2024, essential and non-essential metals in coconut milk
• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984)

Granola is oats and nuts, the two things at the top of the nickel table, bound with syrup. Nothing in it is extreme on its own; the combination and the bowl size are what put it here.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake

Milk chocolate is moderate for one arithmetical reason: it contains less cocoa. Milk and sugar make up the difference and neither carries nickel, so the level tracks the percentage on the wrapper.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Miso is a concentrated soybean paste, so gram for gram it carries the bean's nickel - but it is used a spoonful at a time in a bowl of broth. The level reflects that portion, not the paste in the tub.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Oyster sauce is reduced oyster extract, and oysters filter seawater for a living. The reduction concentrates what they filtered; the small pouring portion is what keeps this moderate. The second French Total Diet Study ranks the food groups for nickel rather than valuing them, and tofu heads that ranking.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Peanut butter concentrates a legume into a paste, so the nickel comes from the urease route rather than from a tree nut. It is eaten in far larger quantities than roasted peanuts ever are.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake

Soy butter is ground soybean, closer to the whole bean than the drinks are, but spread thinly. The level sits between the two for that reason. The second French Total Diet Study ranks the food groups for nickel rather than valuing them, and tofu heads that ranking.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Soy cream is a thickened soy drink. It carries less nickel than the bean but more than a splash suggests, because cream goes into a sauce for a whole dish rather than into one cup.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Soy sauce is the soya bean fermented and poured, and the bean is a nickel accumulator - legumes take nickel up as the cofactor of urease. The brine dilutes it and the spoonful limits it, which is what keeps this a step below the bean itself. Tamari answers the same way: the wheat is the only difference between the two, and wheat is not where the nickel is.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Soy yogurt is fermented soy drink, so it carries the drink's nickel rather than the bean's - diluted, but eaten in pot-sized portions rather than sipped.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Tahini is ground sesame and nothing else, so it carries the seed's nickel at paste density. A spoonful in a dressing is one thing; a bowl of it with bread is another.

• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431, nickel content of food and estimates of dietary intake

Tamari is fermented soy in liquid form, poured rather than served. The nickel of the bean is there, diluted by the brine and limited by how little of it goes on a plate.

• Noel L et al., Food Chemistry 132 (2012) 1502-1513, second French Total Diet Study, nickel among nine trace elements

Beetroot juice powder is a root concentrated twice - juiced, then dried. Beet grows in soil all season, so it starts higher than a leaf would.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

A bouillon cube is salt, fat, yeast extract and vegetable powder compressed together. The yeast extract is the part that carries most, and it is the part listed last.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Breadcrumbs are dried bread ground down - refined flour, mostly, with the water taken out. Drying concentrates, but refined flour had little to concentrate.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Cornflakes are maize, rolled and toasted, then usually fortified with iron. The iron added is a mineral salt, and mineral salts carry the ore's companions with them.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

A croissant is refined flour and butter. Both are low, and the butter is genuinely empty - fat carries almost no metal at all.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Fish sauce is anchovies fermented in salt for a year or more, then drained. Fish is low in nickel, and the liquid drawn off carries less than the fish that made it.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Chips are potato and oil, both low, fried in equipment that is metal. The measurable contribution in convenience foods comes from the processing line as much as from the ingredients.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Gluten-free bread is built from rice, maize and starches — cereals too — so removing the gluten does not remove the nickel, and the loaves pass through the same processing equipment the surveys point at. Two national surveys put bread and cereals among the groups that deliver most of the dietary nickel — near the top because they are eaten in quantity rather than because they are concentrated, and neither publishes a figure for a single grain.

• Smart G.A. & Sherlock J.C., Food Addit Contam 4 (1987) 61-71, nickel in foods and the diet
• Flyvholm M-A et al., Z Lebensm Unters Forsch 179 (1984) 427-431

Hummus is chickpeas and tahini, and both are higher than this on their own. What brings it down is the lemon, oil and water blended in - a dip is mostly not chickpea.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Ketchup is concentrated tomato, and tomato takes up more than most fruit. It is also acidic and stored for months, which is the classic setup for a container to contribute a little.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Oat cream is oat drink thickened with oil. Oats are a high-nickel grain, but this is the drink again - diluted, and then diluted further by the fat.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Pasta is refined durum wheat and water. Boiling it in a stainless pot for ten minutes adds nothing measurable - it is long, acidic cooking that draws metal out of a pan, not plain salted water.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Pesto is basil, pine nuts, cheese and oil. Each part is low, and the nuts - the only ingredient that could raise it - are a small fraction of the jar.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Plant-based cream cheese is usually built on coconut oil and starch. Oil carries no metal and starch carries almost none, whatever the nut on the front of the tub suggests.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Plant-based ice cream is mostly water, sugar and fat, whatever plant it names. The named ingredient is usually a small percentage, and the rest carries nothing.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Potato flakes are cooked, dried, milled potato. Potatoes are low in nickel, and peeling before processing removes the skin, which is the fraction that had touched soil.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Nickel has been determined in commercial spirulina supplements by atomic absorption, so the question is a real one and not a guess — but no value for it is published.

• Hynstova V et al., J Pharm Biomed Anal 148 (2018) 108-118, pigments and heavy metals in Chlorella and Spirulina supplements

Tomato powder is dehydrated tomato, so it concentrates the fruit many times over. It is used by the spoonful, which is the only thing keeping it here.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Tomato sauce is cooked tomato, usually in a can. Acid plus heat plus metal is the combination that transfers most, and this is the food where it happens most often.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Tortillas are maize or wheat, and the maize kind goes through nixtamalisation - cooking in lime water, which changes the mineral profile by adding calcium rather than anything else.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction

Vegan cheese is generally coconut oil and starch with flavouring, not a nut preparation - which is why it sits below the cashew-based cheeses. Read the list rather than the category.

• Cabrera-Vique C. et al., Sci Total Environ 409 (2011) 1584-1588, nickel in convenience and fast foods and its dialysable fraction