Tuna and mercury? How much is too much? Is it hurting me, my progress, my fitness?
This is actually the first post idea from an old idea in the teamRIPPED Suggestion Box. It came in from two guys: Ian H. and Matt O. Both asked roughly the same question: How concerned should we be about the mercury content in tuna and fish? Does it hurt us? How much is safe to eat?
Let me start with the fact that I like tuna. I use it regularly. It’s easy to pack and is full of protein. I have read concerns in the past but I didn’t find them compelling enough to change what I do. So for this post I went out to search for some good, reliable info.
Why should we be concerned with mercury?
Fist off, what is mercury? “Mercury is a highly toxic element that is found both naturally and as an introduced contaminant in the environment.” (USGS – Factsheet) Specifically for our topic of tuna and fish, the EPA states: “Mercury occurs naturally in the environment and can also be released into the air through industrial pollution. Mercury falls from the air and can accumulate in streams and oceans and is turned into methylmercury in the water. It is this type of mercury that can be harmful to your unborn baby and young child. Fish absorb the methylmercury as they feed in these waters and so it builds up in them. It builds up more in some types of fish and shellfish than others, depending on what the fish eat, which is why the levels vary.”
An overexposure to mercury is a biggest concern to small children and pregnant women. In low doses even, mercury is linked to slowed development in children, delays in talking and walking, and some learning disabilities. “Impacts on cognitive thinking, memory, attention, language, and fine motor and visual spatial skills have been seen in children exposed to methylmercury (what you would eat from tuna) in the womb.” http://www.epa.gov/hg/effects.htm Adults (men especially) seem to be at a much lower risk.
While this may not be a definitive answer for men. Mercury can build up in anyone’s body and the possibly of adverse effects is enough to really consider how much we eat.
How much tuna is ok?
From there I was actually surprised at how much tuna you can eat and be under the daily recommendations. For men, it was almost 4 cans of light tuna a week (drained). For me, that seems pretty reasonable. Women of childbearing years should stick to around 3 cans of light tuna(drained). Pregnant women should avoid it all together and kids have a range from 4 – 12 oz a week depending on weight. Consumer Reports had a useful table:
| Who | Limit per week |
|---|---|
| Children less than 45 pounds | 4 ounces or less of light tuna or 1.5 ounces or less of white (albacore) tuna, depending on the child’s weight. (Get more details on children and tuna consumption.) |
| Children 45 pounds or more | About 4 to 12.5 ounces of light tuna or 1.5 to 4 ounces of white tuna, depending on the child’s weight. |
| Pregnant women | To be careful, avoid canned tuna. Choose a low-mercury fish instead. |
| Women of childbearing age | About 12.5 ounces of light tuna or 4 ounces of white tuna. |
| Men and older women | About 14.5 ounces of light tuna or about 5 ounces of white tuna per week should be OK, but people who eat fish more often would be prudent to stick to low-mercury types. |
For me, I would really look to limiting tuna for kids and keeping it in moderation for adults. In all my searching there was A LOT of conflicting info. I trust the research that these government agencies have done pertaining to tuna and mercury, so I would feel confident in sticking at or below their suggestions. Beyond that I would encourage you to talk to your doctor and make the decision that you are comfortable with. That may be saying, “I don’t want ANY risk so I am going to cut it out completely.” Or maybe you want to play it safer than the guidelines and only eat 2 cans a week. Both are fine decisions.
Doesn’t this just seem to be true with most everything in life… moderation is the key! Two meals a week with tuna seems very moderate. On the flip side, I would hope everyone would see that eating 5 cans of tuna a day, every day, would be an issue.
Mercury is an issue in other seafood and species of fish too. So if you do eat a lot of seafood/fish, you might want to pick species that are LOW in mercury content. Some examples are: clams, Alaskan salmon, shrimp, tilapia, oysters, pollack, and sardines even. Some that are HIGH in mercury (and that the EPA suggests you avoid all together) are shark, swordfish, king mackerel, or tilefish.
Thanks again for the suggestion Ian and Matt! I hope this gives you guidance to decide how much tuna you are OK with in your diet.
Need a coach?
My email: coachwayne@teamripped.com
IG: @wayne_wyatt
