Mackerel

Studies in people

• Benefit

  Blood fat levels⁶

  Eating mackerel for a week lowered blood fats called triglycerides in healthy people.

• Benefit

  Blood pressure and cholesterol⁷

  In men with mild high blood pressure, eating mackerel daily lowered blood pressure and cholesterol, but smaller amounts did not.

• Benefit

  Blood fats and blood pressure⁸

  In people with high blood fats, eating mackerel lowered triglycerides, cholesterol and blood pressure.

• Benefit

  Blood pressure and heart risk⁹

  In people, eating mackerel daily for two weeks lowered blood pressure and blood fats.

• Benefit

  Blood clotting¹⁰

  In men eating mackerel for a week, mackerel made their blood platelets clump together less.

Found in some samples or products

These come from where it was grown, how it was processed or cooked, or what it was made into. They are not about the ingredient itself, so the signal does not count them.

• Heavy metals in fish³

  Narrow-barred Spanish mackerel fillets can hold lead, arsenic and mercury, and children in Malaysia and the Philippines may be at risk.

• Histamine in retail fish¹¹

  In Egyptian markets, some mackerel and sardine carried bacteria with the histamine-making gene, linked to higher histamine in the fish.

• Parasites in frozen fish¹²

  Frozen mackerel can carry Anisakis worms that may cause allergies even after freezing.

• Dioxins in fish¹³

  Mackerel sold in Japan carried dioxins, and bigger fish tended to hold more of them.

• Mercury in fish¹⁴

  Atlantic horse mackerel build up mercury as they age, mostly in the muscle, so older fish carry more.

• Food poisoning from raw fish¹⁵

  Most mackerel tested from a Taipei market carried Anisakis worms, which can make people sick if the fish is eaten raw.

• Fish parasites in seafood¹⁶

  Mackerel often carry Anisakis worms, and heavier fish tend to have more of them in their flesh.

Single cases of misuse or overdose

One person or one incident, such as an accidental overdose or a mistake in a kitchen or factory. They are real, but a single case does not show what happens at normal amounts, so the signal does not count them.

• Fish poisoning symptoms⁴

  A person nearly died after eating smoked mackerel, with breathing trouble and severe muscle spasms.

• Sudden deep sleep⁵

  A woman fell into deep sleep right after eating mackerel in tomato sauce, and scientists suggest more research is needed.

The signal at the top counts the findings in people and in animal and lab studies. A concern in studies of people outranks animal and lab studies, and “No concerns” needs at least one finding in people. When most findings in people point one way, the page leans that way (“Mostly”), and every finding is still shown. Findings whose study type is not stated are shown but not counted. This page is a reference, not medical advice. It describes what regulators and published research say. Talk to a doctor or dietitian about your own diet.