Is Mackerel Good for Eczema?

Partly: Mackerel can be a nutritious choice for someone with eczema who is not allergic to fish because its omega-3 fats help regulate inflammatory signaling, but it is not a proven eczema treatment.

Can mackerel help eczema?

Mackerel may be part of a balanced diet, but there is not enough evidence here to say that eating it reduces eczema symptoms or prevents flares. Eczema has several possible triggers, and a food that suits one person may cause a reaction in another.

If you tolerate mackerel, there is no need to avoid it just because you have eczema. Equally, there is no reason to force yourself to eat it in the hope of treating your skin. For a broader look at diet, see the best foods for eczema.

How might mackerel affect eczema?

Mackerel is an oily fish that contains the omega-3 fatty acids EPA and DHA. These fats are involved in processes that regulate inflammation, which is one component of eczema. That biological role is a reason researchers are interested in omega-3s, but it does not establish that a serving of mackerel will reduce inflammation in a person's skin.

Eczema, including its common form atopic dermatitis, also involves a disrupted skin barrier and immune responses. Eating mackerel does not replace a skin-care plan or prescribed treatment. Continue using treatments recommended by your clinician, such as moisturizers and any prescribed medicines.

For hydration options, see the best drinks for eczema; drinks are not a substitute for treatment.

What does the evidence say about mackerel and eczema?

The available studies below looked at allergy testing, not whether eating mackerel improves eczema. They cannot tell us how much mackerel, if any, would help with itching or flares.

A retrospective study of 132 adults with atopic dermatitis reviewed skin-prick tests for several seafood allergens, including mackerel. It found seafood sensitization in some participants. A positive skin-prick test indicates sensitization, but it does not by itself prove that a person will have an allergic reaction when eating that food.

A small study of 11 children with atopic conditions, five of whom had atopic dermatitis, compared fish-allergy test results with supervised food challenges. Some children had positive blood tests for mackerel, but none reacted during the fish challenges. The findings show why test results need clinical interpretation; they do not establish mackerel as an eczema treatment or prove it is safe for every child.

Neither study tested mackerel as a treatment for eczema. Evidence about fish allergy should not be mistaken for evidence that mackerel improves or worsens eczema in everyone.

How can you include mackerel safely?

If you already tolerate mackerel, choose a lower-mercury species, such as Atlantic mackerel. Fresh, frozen or canned mackerel can fit into meals; check the label for the species, especially if you are pregnant, breastfeeding or choosing fish for a child.

For adults, FDA fish advice uses a serving of 4 ounces, or about 113 grams, measured before cooking. For people who are pregnant or breastfeeding, the advice suggests 2 to 3 servings a week from its lower-mercury “Best Choices” list, which includes Atlantic mackerel. This is general fish guidance, not a dose shown to improve eczema, and the servings can come from a variety of listed fish.

Cook fish to an internal temperature of 145°F, or 63°C. People who are pregnant should avoid raw or undercooked fish. If the species is unclear, ask a clinician or dietitian for help choosing an appropriate fish rather than assuming every mackerel is low in mercury.

Keep your usual eczema care in place. If you suspect a food is consistently associated with symptoms, note what happened and discuss it with a clinician rather than making broad dietary restrictions on your own.

Who should be careful, and when should you seek help?

If you have a known fish allergy or have reacted to mackerel, do not try it to improve eczema. Reactions to one type of fish can occur with other types, although this varies. An allergist can help interpret tests and advise which foods are safe; do not conduct a food challenge at home.

Parents should ask a child's clinician for advice before introducing mackerel if the child has severe eczema, a known food allergy or a previous reaction to fish. A positive test alone does not always mean a food must be avoided, so decisions about testing and elimination are best made with a clinician.

People who are pregnant, could become pregnant or are breastfeeding, and children, should avoid king mackerel because it is high in mercury. If you take medication, particularly a blood thinner, ask your clinician before using fish-oil supplements; supplements are not proven by the studies above to treat eczema.

Seek emergency help for possible severe allergic symptoms after eating, such as trouble breathing, throat or tongue swelling, faintness, or symptoms affecting more than one part of the body. Use prescribed epinephrine promptly if available and call emergency services.

Seek same-day medical advice if eczema becomes rapidly more painful or red, develops pus or yellow crusting, or is accompanied by fever. A clinician can assess the skin and advise on appropriate care.