What Is Nickel?
Nickel is a trace element found in the body, food, water, and environment. Important distinction: Nickel is not officially recognized as an essential nutrient for humans by major health organizations (FDA, NIH, WHO). While some animal studies suggest it may have biological functions, its necessity in human health remains unproven. Nickel is more commonly known for causing allergic reactions than for any health benefits.
What It's Used For (Potential Functions in the Body)
While not proven essential in humans, research suggests nickel may play roles in:
Enzyme activation - May be a cofactor for certain enzymes
Hormone metabolism - Particularly involving prolactin
Lipid metabolism - May influence fat breakdown
Iron absorption - Potential role in iron metabolism
Cell membrane stability - May contribute to membrane function
DNA and RNA stabilization - Possible structural role
Critical note: These functions are largely theoretical or based on animal studies. The human body can function normally without dietary nickel supplementation.
"Benefits" of Adequate Intake
Since nickel is not established as essential for humans, there are no proven health benefits from supplementation. Any potential roles are speculative:
May support enzyme systems (unproven in humans)
Possible trace role in metabolism (not clinically significant)
The reality: Most health concerns with nickel involve getting too much rather than too little.
Negatives and Health Risks
Nickel is primarily associated with negative health effects:
Allergic Reactions (Most Common):
Contact dermatitis: Skin rashes, itching, redness from nickel-containing jewelry, belt buckles, watches
Systemic nickel allergy: Dietary nickel can trigger eczema, hives, or digestive symptoms in sensitive individuals
Affects 10-20% of the population
More common in women than men
Toxicity Effects:
Nausea and vomiting
Headaches
Dizziness
Respiratory issues (from inhalation)
Skin reactions
Potential carcinogen (nickel compounds; primarily occupational exposure concern)
Kidney and liver damage at very high exposures
Other Concerns:
May interfere with iron and zinc absorption
Can accumulate in tissues with chronic exposure
Recommended Intake/Serving Size
There is NO established RDA or dietary guideline for nickel in humans.
Estimated typical intake:
Average diet: 100-300 mcg/day
Can vary widely based on diet and water source
Estimated "safe and adequate" intake (based on animal research, not official):
Potentially 25-35 mcg/day, though this is speculative
Upper limits:
No official Upper Tolerable Limit established
Some research suggests keeping intake below 600-1,000 mcg/day to avoid adverse effects
For nickel-allergic individuals: Often recommended to limit to 150 mcg/day or less
What to Take With It
You should NOT intentionally supplement nickel. There are no companion supplements recommended because supplementation is not advised.
If concerned about trace minerals in general:
Eat a varied, whole-foods diet
Adequate intake of other essential minerals (iron, zinc, copper) is more important
What NOT to Take With It
Since you shouldn't supplement nickel, this is more about avoiding excessive exposure:
High-nickel foods (if you have nickel allergy)
Nickel-containing cookware (especially acidic foods cooked in stainless steel can leach nickel)
Contaminated water sources
Occupational exposure without proper protection
Who Should Take It
NO ONE should intentionally supplement with nickel. There is no medical indication for nickel supplementation in humans.
Who Should Definitely AVOID It
People with nickel allergy (10-20% of population):
History of skin reactions to jewelry or metal
Eczema or dermatitis triggered by metals
Systemic allergic reactions
Others who should minimize exposure:
People with kidney disease (impaired excretion)
Those with compromised immune systems
Pregnant and breastfeeding women (as a precaution)
Occupational workers with high exposure risk
Deficiency Symptoms
There are NO recognized nickel deficiency symptoms in humans because deficiency has never been documented in free-living people.
In animal studies (rats, goats, pigs), severe deprivation showed:
Impaired growth
Reproductive issues
Changes in iron metabolism
Liver abnormalities
These findings do NOT translate to human health recommendations.
Toxicity Symptoms
Nickel toxicity is much more common than deficiency:
Acute toxicity (high exposure):
Nausea and vomiting
Diarrhea
Headache
Dizziness
Chest pain
Shortness of breath
Coughing (if inhaled)
Chronic toxicity (long-term exposure):
Skin sensitization and dermatitis
Respiratory problems (occupational)
Potential increased cancer risk (primarily from inhalation of nickel compounds)
Kidney damage
Immunological effects
Allergic symptoms (most common issue):
Skin rashes, eczema
Itching, redness, blistering
Hives
Digestive issues in systemic allergy
Headaches
Fatigue
Timing and Food Considerations
This section is about MINIMIZING nickel intake for those with allergies, not supplementing:
For nickel-allergic individuals:
Avoid high-nickel foods during flare-ups
Spread nickel-containing foods throughout the day rather than concentrating them
First exposure in morning may help identify triggers
Cooking considerations:
Avoid cooking acidic foods (tomatoes, citrus) in stainless steel cookware (leaches nickel)
Use cast iron, glass, or enamel cookware
Avoid the first use of new stainless steel cookware (higher nickel leaching)
Food Sources (What to Avoid if Sensitive)
High nickel content:
Chocolate and cocoa
Nuts (cashews, almonds, peanuts)
Legumes (soybeans, lentils, kidney beans)
Oats and whole grains
Canned foods (nickel from cans)
Shellfish
Seeds (sunflower, flax)
Moderate nickel content:
Spinach and leafy greens
Tomatoes
Onions
Corn
Green beans
Peas
Low nickel content:
Fresh meats (beef, chicken, turkey)
Fish (most varieties)
Eggs
Dairy products
White rice
Cucumbers
Cauliflower
Cabbage
Potatoes (peeled)
Apples, pears, berries
Water sources:
Tap water can contain nickel (especially first draw from pipes)
Let water run before drinking
Consider water testing if concerned
Additional Important Information
Nickel Allergy Testing:
Patch testing can identify nickel sensitivity
Blood tests (lymphocyte transformation tests) available but less common
Important for people with unexplained dermatitis or eczema
Occupational Exposure:
Highest risk: welders, electroplaters, jewelry makers, battery manufacturers
OSHA has workplace exposure limits
Protective equipment essential in high-exposure jobs
Environmental Sources:
Jewelry (especially cheap or costume jewelry)
Belt buckles, zippers, snaps
Coins
Keys
Eyeglass frames
Mobile phones and electronics
Stainless steel (contains 8-12% nickel)
Dental appliances and implants
Cross-Reactivity:
People with nickel allergy may react to cobalt and palladium
Nickel in diet can worsen skin allergies
Low-Nickel Diet:
Recommended for people with systemic nickel allergy
Typically limits intake to <150 mcg/day
Should be supervised by healthcare provider
May reduce eczema flares and systemic symptoms by 30-50%
Absorption Factors:
Absorption increases on empty stomach
Iron deficiency increases nickel absorption
Vitamin C may increase nickel absorption
Calcium and coffee may decrease absorption
Gender Differences:
Women are more likely to develop nickel allergy (possibly due to jewelry exposure)
Hormonal factors may influence nickel metabolism
Diagnosis of Nickel Allergy:
Dermatologist performs patch test
Small amount of nickel applied to skin for 48 hours
Positive reaction confirms allergy
Treatment for Nickel Allergy:
Avoidance is primary treatment
Topical corticosteroids for skin reactions
Antihistamines for itching
Low-nickel diet for systemic symptoms
Desensitization therapy (experimental)
Bottom Line
Unlike molybdenum, nickel is NOT an essential nutrient that you should supplement or worry about getting enough of. The primary health concern with nickel is getting too much or having an allergic reaction, not deficiency.
Key takeaways:
No proven need for nickel supplementation in humans
10-20% of people have nickel allergy
Focus should be on avoiding excessive exposure, especially if allergic
Found in many foods and environmental sources
If you have unexplained skin rashes or eczema, consider nickel allergy testing
A normal varied diet provides any trace amounts the body might theoretically need
If you have nickel allergy, work with a dermatologist or allergist to manage symptoms through avoidance strategies and a low-nickel diet if needed.