I know there are lots of people (and I used to be one of them) that think canned tuna is a healthy option because it provides a) protein and b) omega-3’s. But did anyone stop to think about the mercury levels, putrescine and BPA content? We sometimes become so focused on “nutrients” that we forget about “real” food. Canned fish is pretty much preserved meat after all. When you think logically about it – how can a meat product that’s been sitting in a can for 5 months be good for you?
Now, I know what you’re thinking – “Stace, what the hell is putrescine” …I think you’ll be pretty disgusted.
What is Putrescine and how does it affect me?
Putrescine is a chemical compound of decay that is produced by the breakdown of amino acids in living and dead organisms. It is largely responsible (along with cadaverdine) for the foul smelling odour of putrefying flesh, bad breath and yes, that fishy smell of vaginal infections. Even though it is commonly linked with rotting flesh, putrescine is also found naturally in canned fish, cheeses, meat and fermented foods like wine, beer, sauerkraut, tempeh and kimchi.
What’s so bad about it?
A review published in the Current Nutrition & Food Science Journal, found that putrescine is carcinogenic – meaning it is a contributing factor to CANCER. Compared to most other foods, canned tuna has the highest levels of putrescine. Most of the foods tested contained under 25mg/serve, whilst canned tuna contained about 170mg/serve. Yikes! A safe level of putrescine intake is less than 40mg per meal; just two bites of canned tuna has already pushed you over the safe limit! To put it into perspective, you would have to drink 10 beers to approach the limit.
Let’s talk BPA
Bisphenol-A is notoriously known as a chemical compound found in plastics. It is the substance found in plastic drink bottles and is also used to line the inside of metal cans. Scientists compared BPA levels of over one hundred fresh and canned foods, foods sold in plastic packaging and in cat and dog food in cans and plastic packaging. Nearly all of the canned foods were contaminated with BPA and the only other non-canned food that had detectable levels was sliced turkey.
What’s so bad about it?
BPA has major hormonal implications and has been linked to sexual dysfunction in men. Loss of sex-drive, difficulty in getting an erection, lower ejaculation strength and a lower level of overall satisfaction with sex-life are just some of the problems men with high levels of BPA in their system have. What about women? Hormonally mediated cancers like breast cancer can be exacerbated by BPA because of its effect on the endocrine system; BPA has been shown to mimic estrogen. It particularly has an effect during rapid stages of development, like in early childhood and in the womb. It can cause abnormal penis development in males, early sexual maturation in females and is linked to childhood obesity, type-2 diabetes, cardiovascular disease and neurobehavioural problems like ADHD and autism.
Mercury – Food [not] for Thought
Yes, we’re probably all well aware that mercury is bad for us. But, do you know why? It is heavily implicated in impairing neurological development. In pregnant women, mercury ingestion (from fish) can adversely affect the baby’s growing brain and nervous system. It has a major impact on cognitive thinking, memory, attention span, language and fine motor skills. Not pregnant? Mercury still affects people regardless of life-stage. Mercury can permanently damage the brain and kidneys in large doses. It can cause irritability and anxiety, tremors, changes in vision, memory loss and hearing problems. Think the omega-3 benefit outweighs the risk of mercury toxicity?
Think of it this way:
One can of tuna is equal to 100 medical vaccinations that contain thimerosal (a mercury based preservative). Eating one can per week is also equivalent to having 29 mercury fillings in your mouth. If you have mercury fillings (also called amalgam fillings), everyday, you are slowly ingesting a toxic chemical.
Tuna isn’t the only food source that contains high amounts of omega-3’s either! Chia seeds, walnuts, dark leafy green vegetables, pumpkin and micro-algae (which is what fish eat) are wonderful sources of omega-3 fats that you can freely eat without getting worried about mercury. Plus, you don’t have to worry about putrescine or BPA’s either because you’re eating fresh food!
Have any questions? Enjoyed this post? I want to know! Please comment below or e-mail me firstname.lastname@example.org.
I hope everyone has had a wonderful weekend!
Love Stace x