Nickel is a silver-white metal found naturally in the environment and known for its strength and resistance to heat and corrosion. While manufacturers often use it with other metals in items like jewelry, coins, and keys, you can find small amounts of nickel in many foods, including certain grains, fruits, vegetables, chocolate, tea, and much more.
While nickel is present in a variety of food items and materials, it can cause an immune response in certain people. For those with a nickel allergy, eating foods containing nickel can cause symptoms like rashes or stomach aches.
Why You Should Eat Less Nickel
Approximately 8% to 19% of the population in Europe has a nickel allergy {Contact Dermatitis: “Nickel allergy and allergic contact dermatitis: A clinical review of immunology, epidemiology, exposure, and treatment.”}. This is usually a reaction to physical touch, like touching a piece of equipment made of nickel. However, other people react to nickel introduced through their diet. Even in low doses, their skin can still react in a similar manner. This skin allergy produces contact dermatitis, which includes symptoms like redness, irritation, inflammation, or rashes on the skin.
In others, the reaction goes beyond skin irritation. Symptoms can include headache, stomachache, and respiratory symptoms. This is more commonly known as Systemic Nickel Allergy Syndrome (SNAS).
Doctors also link this sensitivity to nickel to experiencing symptoms of fibromyalgia, chronic fatigue, and other chronic diseases.
However, it's important to keep in mind that those without nickel sensitivity should be safe to consume moderate levels of nickel in foods. Before you eat a food that is high in nickel, consider eating another food first. Taking in nickel on an empty stomach can increase the effects.
Foods With Nickel
The level of nickel in foods depends on the plant species and the nickel in the content of the soil. In the case of seafood, it depends on the aquatic environment. However, some sources of food are known to contain more nickel than others. Here are a few high-nickel foods to avoid.
1. Flour and Grains
Studies have shown that wheat flour contains 12.70 milligrams per kilogram. Other types of grain have also been found to contain high levels of nickel, including:
- Oats
- Buckwheat
- Whole wheat
- Wheat germ
- Multi-grain breads and cereals
- Unpolished brown rice
2. Seeds
Sunflower seeds, sesame seeds, and alfalfa seeds are known to contain a moderate amount of nickel. However, not everyone will be sensitive to these seeds, so it’s best to eat in moderation.
3. Seafood
Seafood and shellfish, including shrimp, mussels, and crawfish, contain high amounts of nickel. A study found that some types of fish contain 0.08 milligrams of nickel. People with a nickel allergy should avoid fish, as nickel amounts vary by type and may be hard to track.
4. Legumes
Certain types of legumes contain high levels of nickel, including:
- Chickpeas
- Lentils
- Peanuts
- Soybeans (and other soy products, including tofu)
5. Vegetables
Research shows that green vegetables contain 0.11 milligrams of nickel compared to other vegetables with a nickel content of 0.09. While not all vegetables contain amounts of nickel, the following vegetables should be avoided or eaten in moderation:
- Peak
- Leeks
- Cabbage
- Kale
- Spinach
- Lettuce
- Bean sprouts
6. Fruits
You can eat most fruits safely due to their trace amounts of nickel. However, figs, pineapples, prunes, and raspberries are more likely to trigger a reaction in people with an allergy.
7. Chocolate
The fat in cocoa beans can increase the potential reaction with nickel. Studies have shown that the high nickel content in cocoa is irrespective of the nickel content of the soil. Avoid chocolate and cocoa drinks. If you do eat chocolate, look for low-fat varieties of milk chocolate.
Nickel-Free Alternatives
If you’re reactive to foods containing nickel or you’re experiencing flare-ups, your doctor may recommend a low-nickel diet. These are some alternative foods with little to no nickel.
1. Corn
Instead of wheat-based foods, corn alternatives have only slight traces of nickel. Foods like cornmeal, corn tortillas, cornflakes, or cornstarch can safely replace wheat or grains.
2. Meats
All non-seafood meats contain low amounts of nickel, including beef, chicken, sausage, ham, and kidney. In general, poultry contains 0.04 milligrams of nickel per kilogram. These are all great alternatives to shellfish and seafood to get your daily amount of protein without risking a reaction to nickel.
3. Fruits
Most fruits, including pears, strawberries, apples, grapes, and most berries, are safe to eat on a low-nickel diet. However, eat raspberries and bananas in moderation.
4. Polished Rice
For rice and rice-based products, look for polished rice instead of unpolished. Rice is considered “polished” when the husk, bran, and germ are removed. White rice is typically polished and safe to eat.
5. Root Vegetables
Root vegetables—like potatoes, carrots, beets, sweet potatoes, and onions—contain only trace amounts of nickel and are safe to eat for those with sensitivities.