Tuesday, July 23, 2024

Should you be worried about Mercury in Tuna?

February 16, 2010 by Ange  

A recent report found that more than half of samples of brand-name canned tuna contained more mercury than deemed safe by the U.S. Environmental Protection Agency (EPA). However, the same report found that only 5 percent of canned tuna samples contained mercury levels that exceeded the U.S. Food and Drug Administration’s (FDA) standards for safety, which are less stringent than the EPA’s. In other words there seems to be a large discrepancy over what constitutes ’safe’ levels of mercury.

We are exposed to different types of mercury: elemental, inorganic and organic mercury. Organic mercury is considered the most toxic and most common form and is the type found in Fish [1]. This form of mercury can be easily absorbed in the gut and can cross the blood brain barrier.

Once in the body, mercury can inhibit other important minerals such as zinc and selenium. It can cause problems with digestion,  the heart, kidneys & nervous system. It can inhibit white and red blood cell formation and cause dysfunction in the immune system. In other words, we really don’t want any mercury in our bodies! We are able to detoxify and excrete mercury, but this in itself will use up the bodies antioxidant and detoxification resources. It is also very individual. If someone is already in a weakened state then their ability to detoxify and eliminate any mercury will be severely compromised.

So, if we are trying to avoid mercury, then should we avoid fish? It is the larger fish, such as tuna and swordfish, that are more likely to accumulate toxins such as mercury (it seems to be a simple case of the longer they live and the more they eat then the more mercury they can accumulate). So the best advice is to avoid these fish if your health is at all compromised or if you are pregnant or trying to conceive (as organic mercury can cross the placenta). For everyone else, then I would suggest that limited amounts of these fish, say once a week or once a fortnight is absolutely fine. Fish, especially oily fish, are a great source of the very long chain fatty acids, which we can’t find in many other foods. So do try to include other, smaller types of oily fish, such as Mackerel and Sardines. There are some recipe ideas here: http://fabulousnutrition.co.uk/good-fish-dish/

If you are concerned about mercury toxicity then seek the advice of a nutritional therapist. If the signs and symptoms suggest that mercury or other heavy metal toxicity is an issue a functional laboratory test can confirm this and is important to do before undertaking a detox programme.

For more information please contact Angela Walker at Fabulous Nutrition.

Fabulous Nutrition is a London based Nutritional Therapy Clinic, addressing functional imbalance in the body with bespoke nutrition programmes. www.fabulousnutrition.co.uk

[1] Patrick (2002) Mercury Toxicity and Antioxidants. Alt Med Rev. 7(6):


4 Responses to “Should you be worried about Mercury in Tuna?”
  1. got mercury says:

    An easy way to estimate your mercury exposure from eating fish is to check out the free online mercury calculator at http://www.gotmercury.org. Based on the current U.S. EPA and FDA guidelines, the mercury calculator is an excellent way to know your potential mercury exposure risk. You can also use the free mobile mercury calculator for cell phone browsers at http://www.gotmercury.mobi

  2. bukmacher says:

    You post informative articles. Bookmarked !

  3. Couldn?t be written any better. Reading this post reminds me of my old room mate! He always kept talking about this. I will forward this article to him. Pretty sure he will have a good read. Thanks for sharing!


Check out what others are saying about this post...
  1. [...] posts have mentioned the reasons for avoiding mercury, the heavy metal which finds it’s way into our bodies from food (especially fish), water [...]

Speak Your Mind

Tell us what you're thinking...
and oh, if you want a pic to show with your comment, go get a gravatar!

Spam Protection by WP-SpamFree