Higher mushroom consumption is associated with a lower risk of cancer | Hacker News Reader

Higher mushroom consumption is associated with a lower risk of cancer

sciencedaily.com

182 pointslxm87 comments

I don't put any credence on this. As the authors say this study merely suggests a possible relationship that needs to be investigated in a proper RCT.

What I don't like

1. Passive observational studies only. Therefore a huge risk of confounders (e.g. people who generally live a healthy lifestyle).

2. The effect size is not very large, making it much harder to winnow out confounders.

3. Invariably attempts to 'control' for confounders use simple linear models that that come nowhere close to actually controlling for confounders.

4. They generally only control for known confounders. If there is an unknown confounder it will get through and mess up the results.

5. It is really hard to tell what is a confounder and what is a legitimate node in the causal chain. As a simplistic example consider 'controlling' for lung cancer in a study of whether smoking is bad for you. Of course this would take away much of the reason why smoking is bad for you. You need a proper causal model informed by data - something that is hard to do. See Judea Pearl "Causality".

6. Note the heterogeneity of results. This suggests that things are going on that are not captured by the studies. Note also that the types of mushrooms don't seem to matter - a strange thing if there were some magic factor in mushrooms, given how mushrooms vary greatly in nutrient content.

7. Misuse of the term "significant" usually a shorthand for statistically significant. A very different thing from "practically significant, large enough to matter".

I don't think it's realistic to expect an RCT for this. Usually RCT setup for nutritional studies means "locking" people up and controlling every bite of food. However since the study in the article examines cancer risk (i.e. long-term outcome), doing an RCT with the idea of measuring who got cancer and who didn't would mean locking people up for years if not decades, which nobody would agree to.

that doesn't mean that the study is to be trusted 100%, just that it's not always appropriate to say "BS, need RCT", since sometimes studies like that aren't realistic

This post would be a lot more persuasive if you:

1. Suggested a way that a study like this could feasibly be executed as a RCT.

2. Directly addressed parts of the study that you thought were insufficiently modeled.

I think the reality is that it’s very difficult to do both of these things, but it doesn’t mean studies like this shouldn’t be done because they can yield otherwise unobtainable information. Like all studies, they need to be fully evaluated individually on their own merits.

> Suggested a way that a study like this could feasibly be executed as a RCT.

Sadly the infeasibility of a randomized controlled trial does not make the evidence from an observational study stronger.

Great analysis. I wonder, is there a ratings agency for scientific studies? It would be neat to see a score associated with experimental design.

You would find that most studies are complete garbage. Especially social science ones.

And the world needs this exposed... in aggregate!

And unfortunately, many nutrition studies are garbage as well.

From the link, first sentence:

> Next time you make a salad, you might want to consider adding mushrooms to it. That's because higher mushroom consumption is associated with a lower risk of cancer

Who writes garbage like this? They say it’s "linked" but draw causal conclusions anyways.

What do you think would be a correct statement?

"If you're the kind of person who adds mushrooms to their food, you might or might not have lower probability of getting cancer"?

It always drives me crazy, because I'm not sure if I'm that kind of person. Am I a person who doesn't smoke or who only doesn't because it's unhealthy? Am I a person who doesn't eat butter or just avoid it because it might be bad for me? I genuinely think I can't know.

> What do you think would be a correct statement?

"because this is not a properly designed study and there is so much chance that this is pure coincidence or related to a non-captured factor, we don't recommend you do anything about your diet. And you can skip reading this paper as well."

That's kind of the whole point - the study should explicitly state that the new findings (as of now) do not provide any diagnostic about your personal chances of getting cancer, and do not provide any dietary recommendation whatsoever.

It's an interesting finding that may motivate further, more specific studies that can result in something actionable, which has value for researchers in the field but (as of now) it should not be used by general public for analysing their diet.

This, is one brilliant idea folks. If it doesn't exist, someone should make it.

Very much want to see that. It's a project idea of mine.

In my opinion publication bias is a bigger problem than poor experimental design. Do you have opinions on how to fix that?

Register the experimental design before hand and a commitment to publish non-results. That’s the logistical piece. The harder one is the incentive structure in academia that focuses on publishing new/novel research. There should be similar rewards for doing good replication work on significantly important results (eg if everyone based their research on a study that hasn’t been replicated which happens with alarming regularity in the social sciences and psychology). High energy particle physics has this problem now too to some extent and they’re tackling it in other ways (you only have one LHC for example)

This should be possible. I think it is important for scientists to do both novel and replication studies.

One way to improve on the status quo would be to make students do both types of work (the point of a PhD is to demonstrate that you can do research, by doing it. So why not do both kinds). This actually could fit in nicely in the program: first/second years tend to be inexperienced anyway, so they could start by doing some replication work. Halfway through the degree, they switch to novel work.

You are exactly right in all your observations here.

Thank you! Exactly this. I'm gonna c&p it to all the other studies like that I always see.

Just because I don't know how to solve the problem doesn't mean I can't speak about the existence of a problem.

Basically all food studies are garbage because it is impossible to actually control enough variables to make a difference.

Paul Stamets has done some fascinating research around this. Turkey tail mushrooms seem especially potent against cancer. Here's the 2.5 minute story from his TED medical talk of his own mother's brush with late-stage breast cancer with less than 3 months to live and and subsequent recovery with Taxol, Herceptin, and turkey tail mushrooms: https://youtu.be/pXHDoROh2hA?t=540

He's founded a company called Host Defense. The reviews on their turkey tail mushroom product are filled with stories of cancer recovery in both humans and pets: https://www.amazon.com/Host-Defense-Mushroom-Naturally-Diges...

He passively implied on Joe Rogan that there is a significant health hazard when eating undercooked portabellas.

I recently started eating raw portabella mushrooms because they are mentioned in "The End of Alzheimer's" as the most potent mushroom species for neuroprotective effects.

I had NO idea they can be cancerous. So thank you.

The book does not mention if they should be cooked or not. I eat them raw for convenience. I'll stay cooking them now, will that help?

If you're looking for neuroprotective effects, you want to be cooking them to break down the chitin wall.

cancerous or not, the body is terrible at digesting uncooked mushrooms and you probably aren't getting much nutrition from eating them raw.

They taste better cooked anyways, lots of umami once you get the juices collecting in the gills. It's a very steak-like experience...

Had no idea about cancerous effects, but the taste is amazing. As someone who eats meats regularily, my favourite vegan burger is with a grilled portabello in it - it beats all the over-processed stuff they sell nowadays.

Have you had shiitakes?

I love portabellos too but shiitakes are just amazing. I have to think they'd made an awesome vegan burger. Just the thought makes me want to try that.

Haven't tried making a burger with them. I'll add it to the todo list for this summer. :D

Agreed, processed meat substitutes are a solution looking for a problem. Mushrooms are already basically meat.

Mushrooms have very few calories and little protein or fat. A person becomes hungry again soon after eating mushrooms. The only thing they have in common with meat is umami flavor.

I don't like mushrooms. Texture is too weird for my autism. So the meat substitutes are good for me...

To each their own, that's the definitive answer for me.

I am happy to have both options anyway.

Mushrooms = actually nutritional. Fake meat = highly processed oils which are not.

Just because you are on the spectrum does not mean junk food is healthy, kindly from another autistic.

I didn't say it was healthy.

With all due respect, what do autism and texture have to do with each other?

Autistic people often have sensory issues that lead to strong aversions to various types of food (among other things). Very commonly autistic people dislike banana

To be fair, cancer does indeed lower your chances of getting Alzheimers.

What? Never heard this before. Do you have a source?

It was a flip remark. The point is it increases your chances of early death. Can't get Alzheimers if you're dead.

https://news.ycombinator.com/item?id=16866990

Probably not worth bothering your elderly parents over. After 60 your risk of death from cancer starts declining, because other causes dominates your risk of death from cancer. By 90 the cancer risk is less than 10%. https://flowingdata.com/2016/01/05/causes-of-death/

I would like to see the paper - there are so so many obvious confounding factors (age, tastes, diet, wealth, social group etcetera).

Past experience about “miracle” antioxidants (ergothioneine in this case) has shown me how much bollocks there is in popularised science.

I would also be interested how robust the results were to removing each dataset. One fraudulent paper could ruin their conclusions?

P(death|me) dominates P(death|population)!

> After 60 your risk of death from cancer starts declining, because other causes dominates your risk of death from cancer. By 90 the cancer risk is less than 10%.

This may be true at a population level. But only because the "average" person smokes, drinks too much, doesn't get enough exercise, has a poor diet, is considerably overweight, is poor, has poor access to healthcare, and may have worked in a job with exposure to occupational hazards or stresses which damage their body.

If you, as an individual, have none of those, with no family history of early death from stroke or heart disease, then cancer will certainly dominate your risk of death.

There may not be any strong correlation but I think it's always best to look at things like these with the intent to learn what you can as opposed to looking for flaws.

Now, that doesn't mean you dismiss what flaws you find, just don't let those get in the way of what might be learned or what deserves more attention.

I've not read the article, just the comments here, but I have grown my own shiitake mushrooms, and a lot of them. So I've eaten a lot of them too.

I think most people probably don't pay much attention to how foods makes them "feel", but I do and I have for a very long time. Shiitake make me feel good.

> According to the findings, individuals who ate 18 grams of mushrooms daily had a 45% lower risk of cancer compared to those who did not eat mushrooms.

Raw or cooked? I also wonder what the methodology is; it's pretty easy to eat 14 lbs of fresh mushrooms over the course of a year, but almost impossible to eat that weight spread out evenly over 365 days.

> but almost impossible to eat that weight spread out evenly over 365 days

By impossible you mean impossible-impossible or too much of a hustle? In case it's former, I'm quite curious what makes it that way.

It is not too troublesome to keep a sack of, say, dried shiitake. You can grab them as a snack or use them in cooking, but ...

> Raw or cooked?

... that's a good question.

> I also wonder what the methodology is

Same goes for the scientists, apparently:

> Future studies are needed too better pinpoint the mechanisms involved and specific cancers that may be impacted

> By impossible you mean impossible-impossible or too much of a hustle?

Too hard, in terms of finding and preparing them, but also in terms of finding something with mushrooms you'd actually want to eat every day. Unless you're going to count chaga lattes or something, which probably isn't environmentally sustainable unless you live in northern Canada or Siberia.

My breakfast is generally scrambled eggs... if this thing works with cooked mushrooms, I can easily see myself adding them to my daily morning food.

It's probably only mushrooms that grow on wood. I doubt button mushrooms are going to confer much anti-cancer benefit.

45% is massive if it’s about getting cancer in your life, period. Unless the mushrooms are killing you with something else before you get cancer I suppose. They must mention effect on lifespan somewhere?

> Unless the mushrooms are killing you with something else before you get cancer I suppose.

Probably not unless you’re poisoning yourself with heavy metals, pesticides, or fertilizer. E.g. avoid the morels next to apple trees, giant puffballs next to highways, wine caps from the botanical garden, etc.

What's the % reduction for people that regularly eat vegetables in general, for comparison?

A salad with mushrooms?! Where's the science in this?! It is strange that scientists suggest eating raw mushrooms, which contain toxins, one of them being agaritine, which is easily deactivated by heat. In addition, mushrooms accumulate radioactive elements. It's very unscientific tog generalize mushrooms, when they are greatly varying in terms of nutrition and benefits! In Bulgaria, where I'm originally from, people eat a lot of mushrooms, but we never eat them raw! A lot of people in America believe that eating raw foods is healthier! I suggest to those brainiacs to start eating raw potatoes or soybeans!

I eat raw potatoes and love them. Raw mushrooms are great too, what are you on about?

Learn about dosages.

https://skeptics.stackexchange.com/questions/7089/are-raw-bu...

Out of curiosity, how do you eat raw potatoes? I can’t imagine a way that I’d enjoy them.

Well, some people just want to be weird. I recommended his raw soybeans, too!

A quote from Google search: "The main source of concern when it comes to raw potato consumption is a toxic compound called solanine, which can cause headaches, nausea, diarrhea, and even death in extreme cases."

Yes I'm aware, but I don't eat green potatoes. Solanine is near the skin on green potatoes. It's that weird off taste.

https://www.sciencedirect.com/topics/neuroscience/solanine

Solanine isn't even removed by boiling. You are eating the same amount in your boiled potatoes.

That's not true as back in Bulgaria we had a trick - you want to get a fever and skip school, you eat a raw potato. And you can't skip school eating a baked one - that's for sure!

Daily reminder that inferring causation from correlation is a slippery business.

Did you know the S&P500 stock index was highly and 'significantly' correlated with butter prices in Bangladesh for many years?

Its the bread and butter of sciencedaily. Garbage stories every day of the week.

The S&P500 and butter of sciencedaily, rather.

It would be nice to know what mushroom exactly.

For example in pizza they often add something that seems to not even have a proper English name: white mushroom / common mushroom ( https://en.wikipedia.org/wiki/Agaricus_bisporus ), which is cultivated.

Then there are countries with a culture of collecting mushrooms (mainly Slavic countries?) which know a lot of varieties and use them for various sauces and condiments.

Then there are various types of mushrooms used in Asian cuisine.

It is easy to eat 18 grams of mushroom per day -> just some pizza... but I wonder if this really was the most common type, or rather some rarer mushroom. Perhaps something from Japan? Where people live longer.

"Even though shiitake, oyster, maitake and king oyster mushrooms have higher amounts of the amino acid ergothioneine than white button, cremini and portabello mushrooms, the researchers found that people who incorporated any variety of mushrooms into their daily diets had a lower risk of cancer. "

Yeah I mean of course mushrooms that eat wood are going to have most of the health benefits.

The English name for Agaricus bisporus is "white button mushroom".

Unfortunately I don't have access to the full article, but the link from the paper leads to an abstract that describes this study as a survey of 17 other papers: https://academic.oup.com/advances/advance-article-abstract/d...

So likely they're not all based on US consumption of US-common varieties, but I do wish I could find more details.

Brown, chestnut, crimini, portobello and half a dozen other names are also Agaricus Bisporus.

The problem in English is more that it has lots of different names, and a lot of people think some of them refers to different mushrooms (e.g. champignon/crimini/portobello/white/brown/chestnut/button mushroom).

Anything you find sold in Western European stores without a 'proper' name, tends to be Agaricus Bisporus, just at different stages of growth. And half the ones you find with proper names usually are too.

It annoys me to no end as it's about the most boring, bland, tasteless mushroom around.

I recently had the opportunity during the lock down to make use of around kg of saffron milk-cap saffron (aka, red pine mushroom, or Lactarius deliciosus), and it utterly changed my concept of what mushrooms could be.

Until that point, I would have told you that I hated mushrooms - that they tasted like mold, or at best, slightly wet rubber - but the saffron milk-caps were completely different, nutty - almost meaty, with a proper texture. Since then I've been on the look out for more interesting mushrooms in my various local grocers, and look out for recipes that make them shine, rather than just using them as filler.

I picked a lot of mushrooms as a child, to the point I'd sometimes take classmates on detours through the forest near school to pick mushrooms on the way home.

The sheer amount of different tastes and textures is astonishing, despite having always been very cautious about avoiding picking any of the ones that can easily be confused with poisonous ones[1], which meant I also avoided plenty of edible species.

But as a child I hated Agaricus bisporus. I'd pick them off pizzas, and refuse to eat them in other foods. I tolerate them now, in small quantities, but your description is fitting. I think the only reason they remain so popular is that they're "easy" to grow, while for a lot of other mushrooms cultivation is still an ongoing challenge to do at scale.

[1] a caution here to anyone considering picking: pick up a book for beginners; find one that deals with your country and that lists common mistakes local to you and how to recognise them - e.g. people sometimes think they're recognising Agaricus bisporus or related edible Agaricus mushrooms, but are instead accidentally picking a young Amanita virosa, one of the most lethal mushrooms known. It's easy to do safely with a proper book, so I don't want to scare anyone off from doing it, as most places will have plenty of great edible mushrooms that there are no plausible local poisonous ones to confuse them with.

> It would be nice to know what mushroom exactly.

Magic Mushrooms obviously.

> A link to the Penn State article regarding this publication: https://news.psu.edu/story/655156/2021/04/21/research/higher...

> Researchers found that people who incorporated any variety of mushrooms into their daily diets had a lower risk of cancer any variety of mushrooms

Is it really this easy? My gut says no. Perhaps the (future) answer lies here:

> Future studies are needed to better pinpoint the mechanisms involved and specific cancers that may be impacted

Did they make risk adjustments for any confounding factors? It seems like all they found is correlation so it doesn't necessarily follow that eating mushrooms was actually the reason for the reduced risk.

This will sound simplistic, but do hospitals/doctors conduct any type of general questionnaire about patient lifestyle details (general habits, type of food/drink consumed, sleep habits, type of shampoo/toothpaste/hand cream they use, where their drinking water comes from, etc) that could be used for cross reference in relation to whatever disease/cancer they have?

I feel like given the sheer number of healthcare patients, we should be able to identify trends with a few simple Excel formulas. E.g. People are more likely to get ${disease} who drank well water from ${location} between ${yearStart}-${yearEnd}

It's worth remembering that healthcare industry decision-makers (on the business side of things) aren't naturally incentivized to actually fix any major healthcare issues...their focus is how to maximize profit, and reducing the number of patients doesn't align with that. In other words, it feels like something there is ripe for disruption.

Self-reported studies are bunk and relying on them is bunk science as far as I’m concerned. We know that non-response and outright lies are a problem. So you’ve got a garbage in garbage out scenario.

There may be places where surveys are scientifically justifiable but I have yet to see such beyond basic preference ones. Even in simpler cases like political surveys there’s lots of problems and they fail us with regularity. Do you really think more complex applications somehow avoid the problems?

Rather than asking patients directly, they could at least use their previous addresses to deduce many things, such as water supply source, air pollution, etc (while keeping it anonymized). The govt could even run studies on cancer deaths cross referenced with location data from their tax returns, and their parent's tax returns (to figure out where they lived as a child). I'm just saying I've never heard this common sense approach actually discussed.

It just seems like we often ignore the concept of "an ounce of prevention is worth a pound of cure".

This seems like exactly the sort of thing that would be susceptible to spurious correlation.

Medicinal Mushrooms: Their therapeutic properties and current medical usage with special emphasis on cancer treatments

https://xn--c1atere.xn--p1ai/upload/files/_education_documen... (PDF)

It is likely that people who eat more mushrooms also eat more vegetables. This correlates to an overall healthier lifestyle.

What I don't like about statements of this kind is that they're couched in apparently careful language of "being associated with" while implying that mushroom consumption reduces cancer risk .. i.e. a causal mechanistic connection exists between them.

If we make that jump ourselves, they can weasel away with "we didn't say that". But then what are they exactly saying? "We just say it is associated with"? .. so if I am supposed to use this information correctly, how should I go about it? ... No I can't do anything with it .. except maybe if I'm a doctor assessing the cancer risk of a patient and I ask "how many mushrooms do you eat per day?" and use the result to adjust the risk. The patient may just ask back "what kind do you use?".

Maybe it's just because people who love to eat mushrooms have better health habits.

I think this is because, mushrooms are known to increase levels of NAD+ in our body[1].

[1]https://www.springfieldwellnesscenter.com/mental-health-blog...

this does not look like a legit medical site with well referenced articles, and it's assertions don't seem to be backed up anywhere else. Cancer tends to increase NAD levels in the body as well, does that make cancer good?

unless there is a clear indication they controlled for bmi, meat consumption, alcohol consumption, body fat, I wouldn't waste much thought about such nutritional studies.

I’m tired of studies like this. More of this, less of that, a glass of this…

How the hell do you get away with writing an article like that in 2021 and not make a single mention of "cofounders" or some such in the abstract (or in the news story, for that matter)??

Correlation does not equal causation.

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