How much tuna is too much?

Recently, the US Food & Drug Administration (FDA) together with the Environmental Protection Agency (EPA) issued advice regarding fish consumption for women who are pregnant or may become pregnant, breastfeeding mothers and young children. The information is aimed at helping those groups eat sufficient amounts of healthy fish, while keeping mercury consumption within safe limits.

However, a subsequent statement issued by the Center for Science in the Public Interest (CSPI) contradicts some of the advice given by the FDA/EPA. CSPI Senior Scientist Lisa Lefferts said that following the advice from the government on mercury and tuna could result in pregnant women or small children consuming more mercury than is safe for developing brains.

The CSPI statement advises that pregnant or nursing women and parents of small children should choose fish that are low in mercury and high in omega-3 fatty acids, like salmon and sardines. They suggest avoiding albacore (longfin) tuna altogether and consuming tuna labelled as ‘light tuna’ very sparingly — no more than 56 g per week for women and 28 g per week for kids.

This differs from the government advice which lists light tuna in the ‘best choices’ category, with a recommended weekly intake of 2–3 servings (226–340 g for adults and 113–170 g for young children). Under the official recommendations Albacore tuna is categorised as a ‘good choice’, with a recommended intake of 1 serving/week (113 g for adults, 56 g for children).