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Farmed salmon leads to loss of nutrients, instead eat 'feed fishes' directly (lancaster.ac.uk)
47 points by achow 8 months ago | hide | past | favorite | 94 comments



Author Bren Smith recommends this in his book Eat Like a Fish. He also recommends eating seaweed and mollusks, and that the water of the eastern seaboard may have been mostly clear due to all the filter-feeders.

My general recommendation is to treat meat like a luxurious delicacy and to instead rely on sprouted seeds (legumes, nuts) and other plant parts for protein, until human population and customs can scale back to a point where the carrying capacity of the land and sea can support not only us but so much other life we share the planet with. Strength and resilience through diversity of species. I'm willing to give up a lot of luxuries for this. At the end of the day it's nice to settle down in a shelter with loved ones, all having eaten enough.


I always read general recommendation for diets as conditioned under the culture for which the author lives in. Without the cultural aspect, it always sound like telling people in rice eating cultures that they should all shift to wheat because of lower methane emissions (or asking wheat eating cultures to switch to rice because of lower CO2 emissions, both arguments has a point).

I do want to see a cultural change towards seaweed and mollusks on a global scale. Nutrition rich runoff from farms create a lot of damage in oceans, lakes and rivers, and both seaweed and mollusks are great in picking up that excess nutrition. I would also like to see a change towards consuming overpopulated fish. It is a completely cultural phenomenon that we can have both overfishing and fish overpopulations at the same time (usually not the same type of fish).

I would also like to see a return towards using domesticated animals in order to replace combustion. Waste food should be prioritized towards animal feed rather than bio gas. Household animals used to be a common practice, and it allowed people to eat meat with much smaller footprint. Chickens are also excellent lawnmowers that do not operate on fossil fuels.


Agreed most countries don’t appreciate meat like Brazil, Paraguay, and Argentina. If everyone lived like us the planet would be a lot more healthy and enjoyable.

Ideally Europe would stop farming and restore its forests to an equal percentage of the land as Brazil. Sadly Europe has ignored the environment for millennia and is unwilling to change its ways.


> sprouted seeds (legumes, nuts) and other plant parts for protein

Doing so will drive demand for better diabetes treatments. Managing diabetes is a longer and more nuanced conversation than one can have here. The rule of thumb is that all carbohydrates harm blood glucose control. The best diet is based on your body type. For me (and many others), a low-carb, inulin-rich diet (unprocessed meats, low-starch vegetables) seems to give lower blood glucose increases.

Some claim a low-fat vegan diet will put diabetes into remission, and I'm sure it does for some body types. I can not judge the validity of that claim except that I do not have that body type, and it made my diabetes control significantly worse.


> The rule of thumb is that all carbohydrates harm blood glucose control.

This is untrue. Only simple carbohydrates harm blood glucose control. Complex carbs such as whole grains and fruit aid in it, in part thanks to their fiber. If you have a source that supports your claim, please share it, it must be bleeding edge nutritional science.


I've not seen any research showing that whole-grain carbohydrates have a lower impact on blood glucose than quick carbohydrates. We have only proof by repeated assertion.

My freestyle Libra CGM has recorded the impact of whole-grain products on my body. Whole-grain products consistently spike my blood sugar. 40 g of oatmeal or Bob's Red Mill 10-grain mix will push me up to 100-120 milligrams per deciliter. Whole-wheat pasta, 60g, will push me up about 150-200 mg/dL.

Eating more than 25 g carbs per meal pushes me up beyond 50 mg/dL at the one-hour mark. If I consistently let my blood sugar climb between 75 and 100 mg/dL at the one-hour mark, my fasting blood sugar starts to climb. This is how I learned that low-fat vegan was a bad diet for me. My A1c went from 6 to 7.8 in less than a year.

Too much dietary advice for diabetics is, at best, mythology.


[flagged]


But this is obviously not scalable/sustainable. If everyone wanted to eat grassfed beef that lives in free range fields multiple times a week, we'd very quickly run out of space and other resources. Not to mention you're still contributing heavily to climate change, unless "bio-regenerative" also means restoring the atmosphere for a zero carbon impact.

At the end of the day, we all need to eat less meat.


These "if everyone did X" arguments are very tricky.

If everyone went to buy food at my local grocery store, the 7 billion people in such a small building would cause an enormous humanitarian catastrophe.

I don't think that means there is anything wrong with me shopping there, and I don't think there is anything wrong in eating grassfed free range beef either.


There are actually 8.1 billion humans. Say that everyone wants beef for dinner, .5 lb / person, rounding down to 3 lbs weekly, rounding down to 150 lbs per year. That is 1.2 trillion pounds of beef per year. The real number is much lower due to age demographics, dietary choices, and poverty (about 60 lbs per person, per year in just the US) but let's keep it simple;, "If everyone in the world wanted 3 lbs of grass fed beef a week, how would that work out?"

400 lbs of meat per head of cattle is 3,000,000,000 cows. 5 acres per head of pure grass fed, double number of animals because of average slaugher at 2 years, and that is 30 billion acres devoted to grazing. For context 125 million acres are utilized for cattle (feed and grazing) in the US. Globally that is 3 times more than is used for all agriculture, globally. This is ignoring dairy.

So this is not very tricky. It is wildly unrealistic for grass fed beef to be anything but an extreme luxury food without large numbers of people starving.


> I don't think that means there is anything wrong with me shopping there, and I don't think there is anything wrong in eating grassfed free range beef either.

Why? The first example is absurd and the logic that someone would rely on in making an argument against you shopping somewhere would also be absurd. But the second point is not absurd, as enough people are already eating meat to the point that ecosystems are severely strained.


We have many grocery stores. We have one planet. It's quite reasonable to discuss whether certain people tax it beyond their share.

It's really the size of the range that's a problem. Eating food that eats food is a really inefficient way to get your energy, so you have to offset it by letting that cow range widely. You have to ask: what this that space not doing because it's currently supporting a cow instead? What have you taken away that other people need?


Those kind of discussions generally leads downhill unless people are very willing to partake in open and philosophical discussions. What is a fair share, and what is an efficient way?

All major food production is taxing the planet beyond what it can handle, among those being the use of artificial fertilizers in farming. Using a limited resource like fossil fuels to feed people is extremely inefficient when the ocean and land has plenty enough nutrients already. Using land itself is also fairly inefficient use of space when land is only 30% of the earth, with 70% being covered by water. Nothing beats farming on water when it comes to land efficiency.

Looking at land efficiency a second time, the size of the range is not the only factor. Caribous uses a massive amount of land for very small amount of meat, but the land they use tend to have an average human population per square mile close to 0. Using land located in a rain forests is much worse than using land located within the polar circle. There is a argument that using animal ranges in some locations is both good in term of land efficiency and bio diversity.


There are interesting philosophical conversations to have about fairness and efficiency, but they come up when you're in the ballpark of what some people would consider fair or efficient while some others would differ.

This is not that.

A cow spends its whole life radiating heat into the environment. That's energy that could be powering me. It's a pretty simple watts-in-watts-out calculation, and it's nowhere near efficient.

Sure, maybe no humans want to live where the cows typically graze, but there are other organisms which contribute to carbon capture and clean air and clean water and pollination and disease control... And they are displaced when you've got cows gobbling up all the new growth and preventing forests from forming.

What's unfair is that those ecosystem services are being degraded in service of a few people's dietary habits, and that their loss is subsequently impacting the rest of us.

Yeah, maybe there's a biodiversity benefit to controlling grazer population through hunting, but only as a stopgap until we manage to reintroduce natural predators which don't have to be policed or practice restraint: predator/prey population dynamics are better equilibrium seekers than government regulation re: permits and tags.


Where the ballpark is a good starting question. Is a cow better or worse compared to artificial fertilizers? Looking at the devastation caused by run-off from farms in the baltic ocean, there is a man made underwater desert that is constantly growing with the current size of approximately 100,000 km2. Those dead zones (as they are called), lead to massive death of all aquatic organisms.

If we talking about fairness, food should be sustainable and not causing massive harm to the environment. That seems however to be outside the ballpark of what people consider possible. The question is then where we should start.


There is not enough resources for everyone to eat sustainable beef. Some people need to eat unsustainably, so others can eat the sustainable stuff. Which is, obviously, unsustainable.


Classic tragedy of the commons.


Grass fed beef does not add to Climate change, as all bio-emissions are bound in a cycle. Unlike typical mass production which is importing feed from far abroad, often burning a good chunk of rainforest in the process on doing so.

Not to take away from your primary point, though. I'd much rather have meat be valued as a high quality nutrient source rather than something cheap you can take for granted.


>Grass fed beef does not add to Climate change, as all bio-emissions are bound in a circle. Unlike typical mass production which is importing feed from far abroad, often burning a good chunk of rainforest in the process on doing so.

There are many studies that show that beef, grass fed or not, add to Climate change.

The grass fed meme crowd thinks they are saving the rainforest by not eating beef fed with soy from monocultures in Latin America but conveniently forget that in order to feed the whole world with grass fed animals you would need more land than the world can provide. Much of the amazon is being cut down to create pastures for cattle. It's a complete tragedy.

>Beef cattle use nearly 60% of the world’s agricultural land but account for less than 2% of global calories and 5% of global protein consumed.

https://grazingfacts.com/land-use


It adds a lot. Cows produce a lot of methane which is more destructive than CO2 (though lasts shorter). Also, in transportation, the main contributor is the last mile so "local" produce doesn't necessarily have less contributions per transported unit.


Grass-fed cows still produce methane and require vehicles to transport them when bought and when slaughtered. The fields they are kept in will also need trees to be cleared and plants killed in favour of grass. How does that not add to climate change?


Two can play at this game:

Animal protein raises pressure on your kidneys for hours after consumption. By eating that you are inflaming your kidneys and increasing the likelihood of a wide range of consequences.

Turns out living has consequences no matter how you live. Choose what you are willing to die for.


Also heme iron is carcinogenic[1].

[1] https://pubmed.ncbi.nlm.nih.gov/21209396/


Toxins get accumulated in animals in around a 10:1 ratio. 1kg meat contains 10x more toxins than 1kg plants. A good rule of thumb to remember.


Depends on the toxin. For example, tuna is loaded with heavy metals because it is at the end of the food chain.

However, I think the OP rather meant plant defense chemicals like phytic acid, oxalic acid etc., which as far as I know are not found in meat.


Tigers better watch out too... I hear tuna are working on developing a series of breathing apparatus so they can go on land to hunt and kill tigers.


This is almost certainly not true. Outside of heavy metals there are very few things that "accumulate" in the body and I can't find any papers mentioning nut toxins having this effect.


There is literally an article on the front page about PFAS bio accumulating. Look harder.


Where is the evidence that these are higher in nuts and fruit than in meat and dairy?

The article you mention doesn't answer this question. Read harder

https://medicalxpress.com/news/2024-03-pfas-blood-ubiquitous...


The first study[1] I could find that included analysis of vegan vs non-vegan diets' correlation with blood PFAS levels suggest that vegan diets are negatively correlated with some classes of PFAS (and neutral with the other classes analyzed): "The strongest correlations with food groups, derived from a food frequency questionnaire, were observed between levels of PFOA and water consumption (in case of the total study population, n = 72), and between levels of PFOS as well as PFNA and the consumption of ‘meat and meat products’".

I'm not proposing that a single study is proof, but I'm default-skeptical of dietary claims without strong evidence, especially ones that comport with other aspects of worldview or preference.

[1] https://www.sciencedirect.com/science/article/pii/S143846392...


If he had said “Very few people has actually been to the moon”, would you had commented “Here’s an article about an astronaut.”?


PFAS is a “plant defense mechanism”?


Plant deFense mechAniSm


You'll note I wrote "there are very few things", not NO things. Read more carefully before rage posting, please.


These are all mitigated by a balanced diet, while deriding diets high in nut content you also neglect to mention that eating large amounts of beef significantly raises your risk of multiple forms of cancer.

Not to mention that side effects like those caused by almond consumption, would require eating hundreds of grams of almonds a day.

So you're not quite being fair here.


What amount of optional toxins is balanced? Why not just eat less toxins?


You'd be hard pressed to find anything absolutely toxin-free. Many toxins have non-linear effects, negligible at very low doses, so there are advantages to diversification.

Even if you could find a handful of foods that are absolutely toxin-free, eating only those would greatly reduce the diversity in your diet.

The obvious optimum is a diet minimal in the effect-weighted sum of its toxins, subject to the constraint of also providing healthy levels of all essential nutrients... which the GP is attempting to reasonably approximate without requiring years of research into the exact diet by proposing toxin risk diversification.


Eating a primarily organic, whole-food, plant-based diet avoids lots of toxins that build up along the food chain, while still offering a huge diversity of foods.

There are far, far, more species of plants to eat than species of animals in human diets.


Water is a toxin in high quantities, it's not a "poison or not poison" situation


Right, but it's also "all diets have some level of toxins so they are comparable".

Primarily whole-food, plant-based diets have the lowest level of toxins.

For example, see the Cleveland's Clinic recommendation for a low-inflammation diet which recommends diets like Mediterranean, DASH and whole-food vegetarian.

https://health.clevelandclinic.org/anti-inflammatory-diet


Simply avoid all protein sources?


Do you mean animal protein sources? Yes, that's a good idea.

There's plenty of protein in plant foods.


I thought we agreed above that plants were also toxic.


This is complete pseudo-science BS.


How do plants defend themselves? Do you know what apple seeds contain? Have you researched cashews yet? Do you cherry pick what science you think is real science!


Cows do an outstanding job turning grass and other inedible things into a foodstuff that not only has extreme nutritional value, but resonates with me on a cellular level.

It'd be cool if we can grow steak in future, but I think it'd be very hard to replicate an actual cow without adding toxins, and I worry that they'll make some ridiculous low-fat or low-cholesterol version based on nutritional "science".


Cows are extremely inefficient. How can you say they do an outstanding job? Outstandingly high emission of Methane belching?


Efficiency isn't the only way to do an outstanding job.

When Michelangelo painted the Sistine Chapel, it took him forever to paint a small surface. Any old housepainter could have been more efficient.

The point is that grass is inedible and grows all over the place, and cows turn this abundant and useless resource into wonderful steaks.


Cows are literally one of the least calorie-per-CO2 efficient means of getting meat. Here's some actual data: https://ourworldindata.org/grapher/ghg-kcal-poore

You'll note that beef is by far the worst.

Here's one that better describes the components of that CO2 footprint (whether it's methane production, or transport overhead, etc.): https://ourworldindata.org/food-choice-vs-eating-local


I refer you to my reply to your sibling comment.

Michelangelo did a less efficient job painting the Sistine Chapel per square meter than a housepainter would have.


One should just stop eating fish as far as possible. Between all the worlds ocean ecosystems being in trouble and the risk of ingesting heavy metals it is just not worth it.


There's a geopolitical issue regarding countries with ample farm land and islands for instance with moatly sea resources though.


About their recommendation: one thing I never understood was, how can we at the same time say we are overfishing and that people should eat more wild fish?


It's been a while since I read "The Perfect Protein" by Andy Sharpless, but IIRC their argument is that it's not just fish, but particular populations of fish. Some wild fish are fine to eat - others are either at risk or are keystone species that shouldn't be wiped out. Also the method of fishing makes a difference as well. Hence the contrasting advice.


Those are good points. I guess it's still possible to tilt things in the wrong direction, but we can always adjust.


I wonder if anchovy and mackerels are overfished. I'm not sure as we don't see them often on the table and there's few reports outside of California.

In this specific case, even if they wouldn't be the best food source in general, they would still be better than salmons (which we eat plenty of) in terms of food efficiency.

This notion of shortcuting the production cycle is really intersting to me. If for instance instead of drinking milk we'd get equivalent nutriments from straight eating grass based products, that would open a lot of ways for improvement.


I don't know about nutrition and overfishing, but mackerel are incredibly tasty to me.


They're giving advice based on that's good for the individual, which can be at odds with what's good for the collective.


Not all fish are overfished. Even salmon isn't overfished in all regions.


We can't. The fishing fleets are on a path to totally wiping out Herring in the Baltic Sea for example. So the article misses the point on that front too. The government of Sweden is doing nothing while the population collapses.


It's the same story on the land. It's healthier and better for the environment eat lower down the food chain.

A science-based book on the topic is How Not to Die by Dr. Michael Greger, which review nutrition studies related to a range of terminal diseases. Primarily plant-based diets come out as being best for longevity.

Folks who study longevity specifically reached the same conclusion that a 95% to 100% plant-based diet was good for longevity.

https://www.bluezones.com/recipes/food-guidelines/


Sardines are awesome, they make boneless skinless fillet now which substitute well for tuna (I seem to always get a bone stuck in a tooth so prefer no bones despite being tasty).

That said, sushi from sardines seems dicey.


Fishing in the wild without restocking the fish population is simply a form of poaching.


Restocking could have the same effect as replanting trees: numbers stay the same so it absolves the industry.

But the ecosystem is still getting worse as it gets devastated by the constant churn and artificially restored new areas are not as diverse as the original one.


I'm pretty sure wild fish restock themselves by reproducing, it's more about finding the equilibrium it converges to and not overfishing.


In Vietnam, marine wildlife sanctuaries help enormously. Fisherman are banned from fishing in certain areas, but can fish with great success around those areas. The protected areas allow stock to be replenished. It’s the goose that laid the golden egg phenomenon.


Overall, this suggests that farmed salmon loses some nutrients compared to the wild fish it eats and that we're better off eating a more varied diet of the wild fish species that are fed to farmed salmon, such as sardines, mackerel, and anchovies.


Big salmon (I say that in a somewhat tongue-in-cheek way) seems to have a chokehold on all food suppliers. I swear salmon makes up 90% of the fish I see sold almost anywhere apart from a specialised fishmonger. I find it really wierd


Salmon is tasty


It's because almost all other fish tastes kinda bad except for trout, which is basically salmon. This is the market catering properly to the buyers.


This is such a narrow-minded view. The reason you think that is because you're from a country that lacks fish culture, where very few fish dishes are served. In Japan or Italy, they eat every single type of sea creature that could possibly exist and they eat them fresh and its a big part of their culture. In japan, there is sushi of every single sea creature that can possibly be eaten. Salmon is one option. So your view that salmon is the only good fish is completely cultural.

I'm from the UK and despite being an island we have no fish culture. We used to have more, but the supermarkets that have a total chokehold on our food lives have severely limited the variety (and freshness) of fish available, making us squeamish about foods that were an integral part of our culture (eels, cockles, smoked fishes of many kinds). This is a horrible horrible loss to the diversity of our diets and to the populations of the few fish people still eat (cod and salmon).

The lack of fish culture that makes you state such an opinion is most likely caused by unsustainable, monopolistic supply chains that have shaped culture, it is not an objective fact.

Luckily, I have carribean heritage and a degree in Japanese and so I have exposure to good fish from other cultures. You know, people make fun of the fact that the British used to eat eels, but in Japan, eel is seen as the most premium, most delicious food you could possibly eat? It's more expensive than steak to eat at a restaurant, it's so sought after. Salmon doesn't hold a candle to eel.


I find it hard to believe you genuinely think almost all fish tastes bad. At the very least, you understand this is an idiosyncratic view, right?

I cannot imagine this being a common view unless you just haven't tried many fish varieties


People in the replies sure seem to have a hard time accepting that markets aren't personal. It doesn't matter what you think tastes good. What matters is that buyers where this observation is being made think that salmon and trout taste good and that other fish do not. This is a very common situation in the US. You don't need to be offended by it or talk aggro-defensively about how your fish culture is superior to someone else's. The rise of salmon consumption isn't a conspiracy. It's just a flavor profile that agrees with the masses.


Did you read my reply. You are objectively wrong and I explained now. Your fish culture is caused by the industrialisation of food, which is what makes you think only salmon is good. Your point would only be valid if salmon was universally nicer to everyone. Like salmon is some inevitable singularity of fish consumption.


Have you tried fresh halibut? I don't like fish generally, including salmon, but actual Alaskan halibut (not flounder deliberately mislabeled as halibut) is quite tasty, to me.


Fish fed to farmed salmon should be part of our diet, too, study suggests

is the actual title


And "leads to loss of nutrients" definitely makes it sound like "this is leeching nutrients from your body", not "there isn't a 100% transfer of nutrients from feeder fish to salmon to you"


For ~200k years, humans got food from hunting and gathering. You went out in nature and caught the food you could find growing wild there. That supported a global population of ~50M.

10k years ago we started figuring out how top make food ourselves (farming), and now we can comfortably feed 7000M.

But we still harvest the oceans like hunters and gatherers. I don't think this can or should go on. We need to farm the oceans!


See my comment above. Marine wildlife sanctuaries are very effective at replenishing stock.

Also, it’s not always realistic to farm fish. It’s not always possible. And the quality is often much worse given farming practices.


> Also, it’s not always realistic to farm fish. It’s not always possible.

That's completely true with current technology. I'm talking about the long term future.

It took 10k of farming before fertilizers were invented in 1913 and doubled food production.


Yes, much of the ocean is basically a desert due to a lack of iron. Low iron leads to low plankton which leads to low fish counts.

Ocean fertilization could 10x the number of fish, and possibly store some carbon also.


In East Asian cuisine, such as Japanese dishes, mackerel is a common ingredient. Grilled mackerel is delicious. Generally speaking, salmon is a fish with relatively low mercury content, much lower than that of tuna, making it a healthy choice among seafood.


Yes...but hunting/eating further up the food chain is a timeless way to demonstrate that you are further up the human social pyramid. Similar for more heavily processed & elaborately prepared foods.


It's not demonstrative - food from higher up the pyramid is actually denser in nutrients and taste vastly better in my mind (we're talking beef vs lentils, not plankton vs lion).


Plenty of counterexamples. I think scallops are probably the best tasting seafood if not one of the best tasting foods period and they're filter feeders. Shrimp is pretty good as well. Meanwhile, bear tastes pretty bad.


I quite like bear - tastes like a beefier beef. Depends on what the bear ate.


Statistically true. But are herring, pigeons, and rabbits meaningfully less nutrition-dense than large/dangerous/brag-worthy game?


... But if they are higher up the food chain they also accumulate far, far higher levels of heavy metals. This is true for meats and fish.


True, and I vaguely recall a case or few where people showed off their rich tastes (for swordfish steaks, etc.) until their nerves & muscles didn't particularly work together.

But, back during the formative millennia of human nature, that wasn't a problem.


is this a joke? yes, there is obviously a loss of energy and material as waste when go a step, just like in real ecological networks where one animal eating another does not absorb everything its body has to offer for nutrients


It's not a joke, because people continue to eat inefficiently higher up on the food chain.


We aren't so starved so as to have to prioritize eating efficiently, people will eagerly prioritize aspects of taste and eat inefficiently, and it's great that they can do that - it would be horrific and a symptom of unacceptable overpopulation if people couldn't afford to eat "inefficiently" and would have to resort at eating whatever as long as it has sufficient nutrients.


Animal agriculture is a major driver of climate change, so we are already at the point where food choices made a significant difference.

Thankfully, there are plenty of great tasting plant-based foods.


I’d be willing to eat more meat to reduce the population of carbon producing animals.


i’ll take my farmed salmon and you can eat what you want, including the bony and not very tasty feed fish if you so desire




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