Are you eating too much tuna?

With Spring fast approaching, and warmer weather coming our way, I thought I'd do a post on a summer salad favourite, Tuna. Tuna is high in Omega 3, a great source of protein, Vitamin B6, B12, Phosphorus, Niacin and Selenium... aaaand dangerously high in Mercury. 

Ask anyone who considers themselves to be a "healthy eater" and you can bet on them telling you how much they love tuna. We eat tuna as a snack, we have it in our lunchtime salad, we buy fresh fillets to fry up for a healthy and quick dinner- we all love tuna! It's a wonderful source of protein, good fats and vitamins, but what the majority of tuna eaters don't realise is these benefits are believed to be outweighed by the extremely high levels of mercury found in our favourite fishy friends. 

So is mercury poisoning a myth? Or can it really be doing some damage to your system? 

Naturopath and Nutrition Communications expert Johanna Clark speaks from experience when she says mercury poisoning shouldn't be taken lightly. 

" As a student of Naturopathy 9 years ago, I thought tuna was the bees knees.  This was before I learnt about the whole mercury poisoning thing.  Which indeed really reared it’s head when I received mercury blood and hair mineral analysis test results back showing that I had extremely high levels of mercury poisoning in my system.  Through research and seeing good practitioners we realised this poisoning was most likely contributing to my gut issues, food intolerances, my poor detoxification ability and possibly my thyroid stuff.This is why I get a little concerned when patient tells me they are having a number of cans of tuna each week or a can a day!"

So why tuna? Well mercury gets slowly built up in the systems of the fish we eat as they absorb methyl mercury in the ocean. All fish absorb mercury, however smaller species don't live long enough/ aren't big enough to absorb enough mercury to be dangerous to us. Tuna and other large fish contain extremely high levels of mercury because they generally live for longer and eat smaller fish in the food chain. The older the fish, the longer it is exposed to mercury, therefore the more it absorbs.

Humans are extremely vulnerable to the toxic effect Methyl mercury has on our bodies, particularly for women who are trying to or thinking of concieving. Mercury poison can not only effect your chances of getting pregnant, but the staggering and alarming effects mercury can have on a developing foetus cannot be ignored.  It is for this reason that large fish species should not be eating during pregnancy and at least 3 months before conception.

For everyone else, you don't need to cut tuna out of your diet completely. Try to keep your seafood intake to 1-2 serves per week, and make informed choices on the mercury levels in the fish you're eating. If you love your larger varieties of fish and can't imagine life without them, make sure you speak to your naturopath or doctor about getting onto a supplement to balence out the heavy metal toxicity in your system. 

The Natural Resources Defence Council has come up with a great info sheet of the best seafood sources. You can find the link here. 

Deffinately stay away from: 

• Shark/ flake
• Swordfish
• King mackerel
• Marlin
• Orange roughy 
• "Bigeye" and "Yellowfin" tuna
• Bluefish
• Sea bass.

 If you love your fish and chips and don't know what to order, try King George Whiting instead! Tastes great and won't do the damage that flake will. 

Some great tuna alternatives: 

• Whiting
• Herring
• Salmon (Make sure it's fresh not farmed!)
• Sardines
• Anchovies