Grains and nickel: 30 foods rated

Amaranth is a high-nickel pseudo-cereal, and it is eaten whole - there is no bran to remove, because the whole seed is the grain.

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

Buckwheat is not a wheat but a seed, and it carries a nickel load closer to the legumes than to the cereals. Its use as a gluten-free substitute means people often increase it sharply without knowing.

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

Millet is high in nickel, which matters most where it is a staple rather than a side - the level is the same, the daily quantity is not.

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

Oats are high in nickel, and it sits in the bran - which is the part oats are eaten for. There is no low-nickel way to eat a whole oat.

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

A muesli is whole cereal, nuts and dried fruit at once, and those are three of the ingredient groups named as raising the nickel of a prepared food.

Cereals and cereal products rank among the highest nickel groups in the published surveys, though none of them measures a rye bread.

Cereals and cereal products rank among the highest nickel groups in the published surveys, none of which measures a spelt bread.

Barley is a low-nickel cereal, and most of it is eaten pearled - the polishing that removes the hull takes the outer layers where trace metals sit.

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

Brown rice keeps the bran that white rice loses, so it carries more of everything the paddy held, nickel included - a genuine difference, though rice starts low enough that both stay here.

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

Cornmeal is degermed maize, and the germ is the fraction that holds the nickel. Maize is low to start with, and degerming takes it lower.

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

Oat fibre is the hull rather than the grain - the woody outer layer, isolated. It carries the nickel the outside of the plant collected, but it is used in small amounts as a bulking agent.

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

Popcorn is whole maize kernels burst by heat - nothing is removed, but nothing was there in quantity either. Maize is a low-nickel grain, and heat does not concentrate a metal.

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

Quinoa carries more than a refined grain and less than oats or buckwheat. The rinse it needs to remove saponins also washes away part of the seed coat, which is where the nickel concentrates.

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

White rice has had the bran and germ milled away, and with them most of what the plant took from the paddy. It is one of the lowest staples for nickel.

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

Rolled oats are whole oats flattened, so they keep the bran - and oats are a high-nickel grain. They sit here rather than higher because rolling is not milling: the flake is a portion, not a flour.

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

Rye is eaten almost entirely as wholegrain bread, which keeps the bran the nickel sits in — the exact form these surveys name. 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

Sorghum is a drought crop grown on poor soil, and a plant cannot take up more than the ground holds. That is the main reason its nickel measures low.

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

Vermicelli is made from refined flour - rice, wheat or mung bean depending on the kitchen - and refining is what removes the fraction that held the nickel.

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

Wheat carries little nickel, and what it holds sits in the bran and germ rather than in the starch — milling to white flour takes them out, wholegrain keeps them. 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

Wheat gluten is the protein washed out of wheat flour - the starch and most of the minerals, nickel included, go down the drain with the wash water. What is left is almost pure protein.

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