Administration (FDA), which sets action levels for contaminants in seafood to protect consumers. For methylmercury, the FDA has established an action level of 1.0 parts per million (ppm) in fish and shellfish, which is equivalent to 1 mg of methylmercury per kg of fresh product.
This limit applies to commercially sold seafood and is used to determine when products should be removed from the market due to excessive mercury levels.
The FDA also provides consumption guidance to help consumers choose fish that are lower in mercury while still benefiting from their nutritional value.
An FDAās TDS Study Ensures the Safety of Canned Tuna
In the United States, an important monitoring is carried out by the FDA through its Total Diet Study, which analyzes common foods ā including canned tuna ā to assess levels of contaminants such as methylmercury. Independent organizations such as Consumer Reports have also conducted tests on popular canned tuna brands, finding differences in mercury levels depending on the species used and the product type, particularly between light tuna and albacore tuna. These studies help inform FDA recommendations on safe seafood consumption and consumer choices.
The research found that the samples showed methylmercury levels ranging from 0.026 to 0.253 mg per kg of body weight, with an average value of 0.099 mg/kg. This confirms the absolute safety of canned tuna:
the presence of the heavy metal is well below the limits set out in the previous paragraph. So, donāt worry; you can safely consume canned tuna without any risk in your daily life.
The only caution is reported by the Food and Drug Administration regarding the consumption of large fish, both fresh and canned, for pregnant or breastfeeding women: in this phase, in fact, methylmercury is more absorbable and could penetrate the placenta or reach the mammary glands, endangering the fetus and child.
In particular, as reported in the useful table contained in the article, it is best to avoid larger tuna (for example, bluefin tuna) and other very large fish, while there is no problem with the consumption of smaller breeds of tuna such as the yellowfin species, which absorbs a very minimal amount of mercury.
But how many times a week is it best to consume canned tuna?
Due to the possible presence of heavy metals, according to the official ARS (USDA Agricultural Research Service) guidelines, the ideal consumption frequency is a maximum of once a week (a standard portion is approximately 50-80 grams of drained product, equivalent to one large or two small cans for adults).
