a little while back I went on the lifting vegan logic YouTube channel and we addressed the top 10
vegan myths, basically a number of ideas that are common in the vegan Community but are not
necessarily supported by the science, I'll link the full video below, it's over an hour long,
but one of the topics we touched on was the health impact of eating fish, so that's what
you'll see today, we talked about the science on the health impact of consuming fish,
types of fish, are there safer types and less safe types, Amounts, is there a safe amount of
fish to consume, and finally we talked about the evidence on contaminants like Mercury and PCBs.
so here is that conversation. okay maybe the most controversial one, "fish is unhealthy".
what do you think about that? actually very similar, I was I was thinking about this and a
lot of similarities with the oil question, so here we also tend to see a faction of more hardliners
that say fish is unhealthy, if you eat fish you're hurting yourself, you're raising risk of disease,
and then there's a softer version that says, Fine, fish is okay, fish is better than the
Alternatives but it's not as good as plants. so there's usually these two levels of nuance,
right, so again we can go through the exact same progression of looking at the evidence, first we
look at people who tend to eat more fish in these population studies, they have lower cardiovascular
disease risks, they have lower total death, they have lower risks of gastrointestinal cancer, lower
risk of neurodegenerative disease. so the blanket claimed that fish is toxic, incredibly difficult
to reconcile or to support that. now, let's look at the specific comparators and the claims that
it's not as good as plants. few people I think disagree that it's better than, say, processed red
meat for example or a large amount of red meat, most people will agree that it is preferable,
where people kind of diverge is this question of the plants, if I'm eating some fish and if I
remove that and if I eat only plants, am I better off? and I often see people making this claim with
a lot of confidence, saying that removing fish, let's say a couple times a week, which those are
usually the recommendations, right, fatty fish a couple times a week, saying that removing that
fish and adding beans or something like that is gonna improve the health effect of the diet,
it's possible, it's an interesting Theory, but we want to look at whether the evidence supports
it, bottonline, right, so there's a couple of ways we can do this, so there are some some studies
that look at direct comparisons, fish compared to plant foods, and isocalorically, it's called
substitution analysis, and this comes primarily from, again, observational studies, because
they're looking at these long-term outcomes, risk of heart attacks, cancer, death, very difficult
to do a randomized control trial looking at that for technical reasons, it's not impossible but
very tough. bottom line, I've seen maybe half a dozen of these, I've seen some that suggest an
edge of plants, I've seen several that suggest no superiority, kind of a tie, the last one that I've
seen published is from last year, 2021, and it looked at all of these head-to-head comparisons,
so they compared red meat, eggs, fish, nuts, whole grains, all to each other head to head. as a rule,
fish outperformed the other animal products, plants outperformed the other animal products,
but there was a tie across the board between fish and nuts and seeds and whole grains. I don't
think there was a single outcome where one edged over the other, so again, grain of salt, it's an
observational study, we don't jump to the firm conclusion that they are definitely equivalent,
but the evidence is suggesting that if there is a difference it doesn't seem to be massive, it's
just not very consistent or very clear, there's no clear superiority there. maybe a better, a more
informative way to look at this is to, rather than looking at these Foods in a vacuum, is to look
at the entire dietary patterns, this is really what we want to know, right, so comparing vegans
to pescetarians, right, that's really the question that people are asking. there's been a number of
studies that have looked at that comparison, there's, Epic and Adventists, which people have
heard of, there's one other from the UK biobank, the design is pretty similar and the results are
actually pretty similar, so just to give you an example from the Adventists health study,
the reference group are the meat eaters so all the results for pescatarians and vegans are compared
to the meat eaters, so for example for total cancer, vegans had a lower lower risk of total
cancer than meat eaters and pescetarians did not. however, when you look at ischemic heart disease,
it was the opposite, the pescetarians were significantly lower than meat eaters but vegans
were not. all cause mortality, total deaths, same thing, pescatarians were significantly lower,
vegans did not reach statistical significance. so it's just a bit too much uncertainty and a bit
too much mixed data to be confident that there's an advantage of one over the other. by the way,
I avoid fish and seafood personally, not because I think it's going to kill me but
because of the externalities, right, primarily for me the environmental impact, absolutely
devastating the environment, so I'd rather, since there's no clear evidence of superiority,
I avoid fish, but that's a personal call, that doesn't mean we're going to make stuff up,
so I'm not... right. I'm not convinced. and we can talk about, there's Nuance, if you're eating
a boatload of fish, we're going to talk about the contaminants in a second,
but there's different types of fish, right, and if you're eating just massive amounts of
swordfish or something like that, that's very high in mercury, yeah, you might run into problems,
but having salmon once or twice a week on top of a plant-Rich diet, is that better, worse
or the same? I couldn't tell you. oh, another thing that's interesting that people often ask,
they often say, well, that's because these vegans are probably not supplementing with
Omega-3s, the DHA and EPA, and so that's why the pescetarians have a little bit of an edge there,
they're probably low in EPA, but if they were taking the algae oil, then they would kick butt
across the board and no other diet would touch them. possible, interesting thing to test,
would love to see a really rigorous test of that with a really well designed vegan diet versus a
really well designed plant-Rich diet with fish a couple times a week, I would love to see it,
until we have that, I don't think we should make these confident statements based on an idea or
a possibility. mm-hmm. yeah, there's other things that people bring up, the saturated fat content of
fish, fish is also going to have a large amount of these unsaturated fats, the Omega-3s, and again,
the outcomes are overwhelmingly positive as we kind of went over. the contaminants,
probably good to touch a little bit on the contaminants because this is a very common
question, so it's basically three, Mercury, PCBs and dioxins. for mercury, there's a really good
study, an analysis looking at the Mercury content in each type of fish, the interesting thing
is there's a massive variation in the Mercury content from the types of fish that are usually
recommended, which is kind of salmon and sardines, and these, both fattier and not too high on the
food chain, and those tend to have very small amounts of mercury, versus these fish that are
larger and higher up the food chain like shark, swordfish, some types of bass. they can have 20,
30 times more Mercury, so that's something to bear in mind, right, to paint everything with
the same brush is not really objective. the issue of contamination is more relevant for certain
groups as well, pregnant women, children, you're going to be more more careful there, but again,
the benefit, and this all comes down to outcomes, we're starting to sound like a broken record
and that's a good thing, because it all comes down... I mention outcomes a lot on the channel,
so... yeah. so you know, we can speculate about the effect of contaminants but you want to look
at the health effects and you typically see, lower cardiovascular risk, lower neurological outcomes
on people eating fish, so if there's an effect it doesn't seem massive and it seems
to be outweighed by the benefits. you know, if people want to play safe and they say, okay,
fine, this is all fine but I'd rather play safe and not eat any fish and get beans and
maybe the algae oil, that's controversial too, whether the algae oil truly delivers a benefit,
but if people want to do that as a strategy, I don't have a problem with it, it's just the
confident claim that it's definitely unhealthy that's not compelling. the PCBs and the dioxins,
actually, when you look at the main dietary sources for westerners, the number one source
are land animals: beef, chicken, pork, account for about a third. Dairy, about a third as well,
and then vegetables are actually number three with about 22% of the PCBs and dioxins that
people are taking are coming from vegetables. fish and seafood are number four at nine percent
and then eggs are about five percent, so if we were looking at the content
of pcbs and dioxins exclusively and jumping from that to food health value, if somebody
is interested in discouraging consumption of vegetables as some people on the internet are,
they could easily latch onto this and say, look, we should not eat salads and go eat fish
and eggs all day because it's going to lower your intake of... I think we all can see through that
argument, the main problem is that it's focusing on one molecule that's present, and not on the
actual Health outcomes, the net effect of the food on health, so just a little bit of nuance there