Is King mackerel Safe for Graves' Disease?
For people with Graves' Disease, King mackerel is worth limiting or using with caution both during a flare and in remission. King mackerel is a large predatory fish that tends to accumulate more mercury than smaller fish.
Status for Graves'
Why this rating?
King mackerel is a large predatory fish that tends to accumulate more mercury than smaller fish. Food-safety guidance recommends limiting high-mercury fish.
People who are sensitive to this ingredient may notice gi. Individual responses vary, so this symptom category does not replace the condition-specific rating above.
Editorial summary
This summary is editorial and is not part of the clinical review. Ratings above are unchanged.
Why king mackerel is on the avoid list
King mackerel is a large, long-lived predatory fish. The joint FDA and EPA advice about eating fish places king mackerel in its choices-to-avoid group, which has the highest mercury levels, alongside marlin, orange roughy, shark, swordfish, tilefish from the Gulf of Mexico and bigeye tuna. Mercury is found throughout the tissue of a fish, so the FDA notes that cleaning and cooking do not reduce it.
Who the advice is written for
The FDA and EPA advice is aimed at people who are or may become pregnant, people who are breastfeeding and children, and the same chart is a practical guide for anyone choosing fish. The agencies do not tell people to stop eating fish; they point out that fish supplies nutrients such as omega-3 fats, iron and choline, and ask people to choose species lower in mercury.
Better choices
The best-choices list includes salmon, sardines, anchovies, pollock, shrimp, catfish, trout, Atlantic mackerel and canned light tuna. Labels often say only mackerel or tuna, so look for the species name: king mackerel and Atlantic mackerel are different fish with different mercury levels.
How King mackerel is rated across conditions
The same ingredient can mean different things depending on the condition. These are the ratings for every condition that has a guide for King mackerel.
| Condition | During a flare | In remission |
|---|---|---|
| Inflammatory Bowel Disease (IBD) | Avoid | Avoid |
| Hashimoto's Thyroiditis | Limit / Caution | Limit / Caution |
| Graves' Disease | Limit / Caution | Limit / Caution |
| Rheumatoid Arthritis (RA) | Limit / Caution | Limit / Caution |
| Multiple Sclerosis (MS) | Limit / Caution | Limit / Caution |
| Lupus (SLE) | Limit / Caution | Limit / Caution |
Other conditions
Sources
Published sources
- WHO Agencies — literature
Clinical review
Reviewed by Morvarid Nikousokhantayar, MSc Nutrition, Certified Naturopath & Nutritionist — last reviewed September 25, 2026.
This is general dietary information, not medical advice. Talk to your care team about your individual triggers.
Want to check a full product against your conditions?
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