Sardine

Studies in people

• No harm found

  Blood sugar control in diabetes⁴

  In drug-naïve patients with type 2 diabetes, a sardine-enriched diet did not improve blood sugar control over six months.

• Benefit

  Blood pressure⁵

  In people with mildly high blood pressure, a drink with sardine peptides lowered their blood pressure over 13 weeks.

• Benefit

  Type 2 diabetes risk⁶

  In older people with prediabetes, eating sardines twice a week for a year lowered their risk score for type 2 diabetes.

• Open question

  Inflammation levels in dialysis patients⁸

  In dialysis patients, eating a sardine sandwich made no overall difference to inflammation, though it helped some.

• Benefit

  Blood cell membranes in diabetes⁹

  In people with diabetes, eating sardine oil made their red blood cell membranes more fluid, closer to normal.

• Open question

  Breast milk quality¹¹

  Nursing mothers who ate sardines had more omega-3 fats in their breast milk.

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.

• Food poisoning from canned fish²

  People who ate canned sardines at one restaurant got botulism, a rare illness that can paralyse muscles and stop breathing.

• Contaminated fish health risk³

  Sardines from some Balkan lakes and bays held lead, cadmium and arsenic at levels tied to health risks for people eating them.

• Cancer risk from canned fish⁷

  Canned sardines sold in Nigeria contained PCBs, and over half the samples showed a possible cancer risk for people who eat them.

• Mercury in fish¹⁰

  Sardine caught in August and September had mercury levels above the recommended safe limit for people eating it.

• Oil and burning chemicals¹²

  Sardines tested along Brazil's coast contained PAHs, chemicals from oil and burning, though most samples stayed within Brazil's suggested limit.

• Pesticides in canned fish¹³

  In canned sardines from Serbian shops, some endosulfan and dieldrin levels were above the maximum limit.

• Metals in canned fish¹⁴

  Sardine samples held more manganese and arsenic than the maximum limits.

• Heart and artery health¹⁵

  Air frying sardines raised oxidized cholesterol, but adding fresh parsley or chives reduced it.

• Radiation in seafood¹⁶

  In studies of sardine muscle, polonium-210 was found most, then lead-210, then cesium-137.

• Fish parasite risk¹⁷

  In this study, no Anisakis worms were found in the 750 sardines checked, though a few turned up in anchovies.

• Heavy metals in fish¹⁸

  Sardines from the Arabian Gulf held cadmium, chromium, copper and zinc above safe limits in their muscle.

• Histamine levels in fish¹⁹

  In retail sardines, fish with histamine-making bacteria had higher histamine levels than those without.

• Mercury in canned fish²⁰

  Canned sardines hold mercury, but their selenium may help protect against its harmful form.

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.