Recently I’ve heard several different people advocate eating a whole-food, plant based diet with fish from time to time. Below is a comment I posted in response to this that I thought would be good to archive here. Their comment was:
My response was: It’s not just mercury or “low-mercury”. But is there any evidence that any levels are safe? And, why consume any levels if you don’t need to? Furthermore, there’s many other significant risks to consider like beta-Methylamino-L-alanine (BMAA) found in the brains of ALS and other neurodegenerative patients, other bioaccumulated environmental toxins like PCB’s, dioxins, pesticides. And of course saturated fat and heme-iron (which may be less of an issue if you’re only eating fish and not often). And when you eat something less nutritious you’re crowding out an opportunity to eat something more nutritious. Plus endotoxins which elicit an inflammatory reaction. Last but definitely not least outside of you there’s the unsustainable aspect. Over a trillion fish our killed every year worldwide. Overfishing coupled with other issues such as industrial/animal agricultural toxins and acidification are creating dead zones all over the ocean around the world. At the rate we’re going the oceans will be empty in our lifetime. All this for what? Now, don’t get me wrong, from a health side I understand there could be some benefit for the general population some claim and there may be an environmentally, more sustainable way to farm fish and with less toxins. But even farm raised fish have significant issues, like the ratios of fatty acids due to not being in a natural environment of eating and swimming. Just over a decade ago I worked for a company that had a fish farm and I was against eating/selling the fish (this was even before I thought about going vegan). This was due to my research finding that farm raised fish are likely to be more harmful than healthy. There is also the problem with not knowing exactly what you’re purchasing. There’s been too many cases where a restaurant or product claims to be one type of fish and it’s something completely different. Usually it’s something very inexpensive and extremely unhealthy like tilapia. The reason I said early that there “could be a benefit to some extent” is because, like you said, it may be easier for most people to limit meat to just eating fish. I recently heard a Valter Longo, PHD say the same thing (video is here). He was concerned that it’s too easy to be a malnourished vegan without being mindful. This doesn’t by any means negate the negative things I’ve already shared. And, it’s really a silly argument if you think about it. If someone is not willing to be mindful about what they eat they’re most likely going to not be vegan, or vegan very long. If we’re going to encourage people to be vegan we must encourage them to be mindful enough to adopt a healthy diet. And that is eating a whole-food, plant based diet. The doctor was suggesting WFPB diet with fish because of fear people may not get enough fatty acids, b-12, and folate (if I recall correctly). But, that’s still suggesting something to be mindful of. So, why not just suggest a WFPB diet with milled flax seed every day (and/or chia seed, hemp seed, etc…) and a small serving of nuts (walnuts and/or pecans). And b-12 is a no brainer really, nutritional yeast is so great and full of other beneficial vitamins and/or just take a b-12 supplement once a week, which is super easy and cheap. That’s not a whole lot to be mindful of. Some women have issues getting enough iron due to, for example, heavy menstruation. This may be caused by any number of issues. Bivalves may be a good option and are considered vegan really. Muscles are very inexpensive and packed full of iron. I would only think this may be prudent in extreme situations, like anemia. Ideally she would first try eating iron rich foods (chickpeas, lentils, black beans, pumpkin seeds, sesame seeds, dark chocolate, etc…) coupled with vitamin c (ascorbic acid) rich foods (e.g. lemons) and allyum foods (onions, garlic) to help with absorption. It may also help to cook oxalate rich foods (like spinach) to reduce anti-nutrients. And do this with every meal possible. So, in the morning eat oatmeal. Seed cycling is good to do as well. Men don’t have iron deficiency issues, that I’m aware of anyways. They have the opposite. Too much iron oxidizes causing inflammation that contributes to heart disease. When we eat from within the animal kingdom the human body has a hard time differentiating/regulating heme-iron. Plant iron on the other hand is much easier to regulate. This happens with cholesterol/physterol too, etc…
There’s no decent evidence that eating low-mercury fish is dangerous, and limiting my meat to just fish makes it soooooo much easier to comply with the rest of the diet. Also, the group with the lowest mortality in the adventist-2 study were pescatarians.”
Some people like to cite the Blue Zones eating fish. This by no means justifies eating fish. Even the authors of the blue zone study state “fish is not a necessary part of a longevity diet but if you must eat seafood elect fish that are common and not threatened by overfishing”. Click here for more information on the blue zone diet.