The Low Nickel Diet for Hand Eczema
Updated: Sep 6, 2019
One of my patients developed a severe case of hand eczema, with itchy blisters on the palms of her hands and sides of her fingers. She wondered if gluten might be the problem, because when she stopped eating whole wheat foods, her rash seemed to improve.
Food allergies can sometimes be a trigger for skin rashes, but it’s not usually my first thought in cases of dermatitis. In fact, the most common allergic triggers are from external exposures, such as skin care products or metal objects.
After this patient underwent patch testing, we found allergies to several ingredients in skin care products. The testing also showed that she was allergic to nickel, a type of metal which is used in all sorts of metal objects.
She avoided these substances for 8 weeks, and her eczema improved considerably. However, she would still have occasional breakouts of blisters, and that’s when we discussed a low nickel diet.
I asked her to cut out all whole wheat products. I also asked her to try to avoid other foods that are known to be higher in nickel, including tea, cocoa, nuts, seeds, and certain fruits and vegetables. Many of these foods are great sources of nutrients, but in persons allergic to nickel, they can trigger rashes. That’s because these foods naturally contain nickel.
In her case, it worked. After 6 weeks, her blisters were just about gone
Systemic Contact Dermatitis: When Eating Certain Foods Triggers Dermatitis
There are several different types of allergic reactions, and this patient was experiencing one particular type, called allergic contact dermatitis (ACD). In ACD, exposure to a substance on the skin surface can later trigger a rash at the site of skin contact. Nickel is a common cause of ACD.
Systemic contact dermatitis (SCD) is a related type of allergy. In this type of allergic reaction, certain substances that cause ACD from skin contact will also trigger a rash from "systemic" contact. For example, patients allergic to nickel in jewelry may sometimes develop a rash after eating foods that contain nickel. (This may come as a surprise, but many foods are naturally high in nickel.)
In nickel SCD, eating these foods may trigger different types of rashes. The classic type is a blistering rash on the hands. Other rashes may also develop, such as an all-over dermatitis or itchy bumps on the elbows.
Nickel Allergy: Avoiding External Contact with Nickel Is The First Step
Before my patients make any changes to their diet, I emphasize how important it is to first avoid external contact with nickel. For most people, this one step alone will often clear up the rash.
To diagnose nickel allergy, experts perform patch testing. In patients undergoing patch testing in the United States, nickel is the most common trigger.
Nickel allergy usually causes rashes 2-3 days after contact, although they can appear just a few hours later or up to a week later. Some people develop red, itchy earlobes after wearing certain earrings. Others have rashes on their stomach next to buttons or snaps, or on their wrist from metal watchbands.
It can be tricky to avoid nickel. It’s cheap and very strong, so it's used in all sorts of metal objects. You can't tell whether an object contains nickel just by looking at it, and you can't tell by the price. Some expensive jewelry items contain nickel, for example.
If one of my patients has successfully avoided nickel (and other known allergens) for 8 weeks, but is still dealing with rashes on their hands or elsewhere, then we'll discuss diet.
A Low Nickel Diet May Help
Researchers have confirmed that nickel in foods may trigger rashes in some people who are allergic to nickel.
In one research study, patients who were allergic to nickel were asked to follow a low nickel diet. The study included 90 patients who were allergic to nickel by patch testing, and who had developed a rash following an ingested dose of nickel. After following the diet for 4-8 weeks, 64% had "obviously" benefited.
In a later study, researchers looked at the doses of nickel that were likely to trigger a rash. The researchers compared a group of 40 nickel-sensitive patients to a “control” group of 20 patients who were not sensitive to nickel. These patients were then given either nickel-containing capsules (different groups received different doses) or placebo capsules.
The results were clear. A higher percentage of patients reacted to very high doses of nickel. Some individuals even reacted to low levels of nickel, levels that were about the same as that in a daily European diet. (The dose was 0.3 mg of nickel.)
None of the control patients reacted to even very high doses of nickel. This means that if you're not allergic to nickel, you don't have to worry about eating foods high in nickel.
The Low Nickel Diet: Instructions
If you’ve avoided contact with nickel-containing objects for at least 8 weeks, but your skin is still flaring, then your physician may recommend a low-nickel diet.
You will have to avoid these foods for at least 6 weeks to see if this will make a difference in your dermatitis. During this time, you’ll continue to treat your dermatitis with medications, and you'll continue to avoid objects that may potentially contain nickel.
By the end of that time, you should be able to tell if following the diet has helped your skin. If you plan to continue avoiding nickel in foods beyond 6 weeks, we recommend consulting with a nutritionist to ensure an adequate nutrient intake.
The Low Nickel Diet: Foods to Avoid
Avoid: Whole wheat foods and oats
May Eat: Rice, corn, rye
Avoid: Beans, lentils, peas, soybeans, spinach, kale, lettuce, canned vegetables, vegetable juices
May Eat: Other fresh or frozen vegetables
Avoid: Dates, figs, pineapples, plums, raspberries, canned fruits
May Eat: Other fresh or frozen fruits
Avoid: Shellfish, processed meats with coatings or fillers, canned meats or fish
May Eat: Beef, chicken, fish, turkey, eggs
Other Sources to Avoid
Chocolate, cocoa powder, all nuts, all seeds, black tea, commercial salad dressings, multivitamins that contain nickel
Dr. Rajani Katta is the author of Glow: The Dermatologists's Guide to a Whole Foods Younger Skin Diet. To receive future updates on preventive dermatology and the role of diet, sign up here.