Hacker News new | comments | ask | show | jobs | submit login
A high-carb diet may explain why Okinawans live so long (bbc.com)
44 points by fraqed 30 days ago | hide | past | web | favorite | 70 comments

For the love of all that is holy, can we please just admit that our current methods for studying nutrition _do not work_, that we need better ways to handle this sort of complex system, and the mean time, the best knowledge we have about what constitutes a healthy diet really can just be summed up as "eat food, not too much, mostly plants". The head spinning speed with which new "scientifically supported" diet announcements come out -- which almost always contradict each other -- is almost certainly contributing to the undermining of the lay person's trust in science at this point.

We need to stop it, stop trying to apply clearly mismatched tools to this problem and reconsider our whole approach.

The idea of "mostly plants" was arrived at using the same methods you don't seem to trust. Why are you ok with that one?

A couple of reasons, it's the only thing that does seem to consistently match across all the studies. Though, there are plenty of counter examples of cultures that have an almost all meat diet and are perfectly healthy, there are other factors involved in those cultures that don't apply to your average first world eater -- the meat is mostly wild caught for instance.

The other one is environmental efficiency. While I don't buy that a vegan diet is the most sustainable diet -- there are sustainable agro-ecology systems that include meat by necessity to make them work, and the vegan diet relies heavily on certain monocrops that massively damage the planet in their own right -- it does seem pretty clear that we cannot continue to consume meat at the rate it is consumed in the western diet and stay sustainable.

The other thing is that it's a really broad guideline, not a specific prescription. As a broad guideline for health and sustainability for those living in western culture, it seems pretty reasonable.

My take away from reading about diets and health has included:

1. We really have a lot to learn about food and biology.

2. Not all carbs are created equally. We may even need whole, new classifications of carbs beyond fiber/starch/etc (just my suspicion though). this is where Keto/meat and fat diets get results. Replacing processed carbs with nearly anything may be an improvement. Doesn’t make nearly anything healthy.

3. Different people digest different foods differently for varied reasons.

Not all meats are created equal and most studies about diet do not control for that. There's a difference between McDonald's beef patty's and grass fed beef.

> Though, there are plenty of counter examples of cultures that have an almost all meat diet and are perfectly healthy, there are other factors involved in those cultures that don't apply to your average first world eater -- the meat is mostly wild caught for instance.

The more obvious and probably more important factor, that doesn't apply to the average first world eater is there are very few of those that have a diet consisting predominantly of meat. Most meat eaters today still have significant portion of their calories coming from refined carbs and they usually avoid fatty meat, which is a staple for those cultures you mentioned.

>"Two reasons, it's the only thing that does seem to consistently match across all the studies."

Not saying I agree (I haven't looked, but surely "all" is an exaggeration...), but if you don't trust the researchers to know what they are doing this could easily be due to bias or including mcdonalds/etc as "meat". Ie, eating less fast food is correlated with not eating meat.

>"The other one is environmental efficiency. While I don't buy that a vegan diet is the most sustainable"

This has nothing to do with health.

> This has nothing to do with health

Are you an agricultural scientist? How do you know that? How do you know the quality and purity of the soil from which the food grows and the aquifiers which hydrate it didn't affect the nutritional quality of the food itself? I think such impacts have already been observed.

>"Are you an agricultural scientist? How do you know that?"

Ok, I should have spoken more carefully. First, I believe that literally every single thing we can observe is correlated with every other thing (although this correlation may be weak/negligible). So there is nothing that has nothing to do with any other thing.

>"How do you know the quality and purity of the soil from which the food grows and the aquifiers which hydrate it didn't affect the nutritional quality of the food itself? I think such impacts have already been observed."

Definitely, there seems to have been a great amount of vitamin/mineral depletion. Usually this is chalked up to intensively farming (high-carb) grains (rice, wheat, corn) that really no animal should be eating much of:

https://www.sciencedirect.com/science/article/pii/S221451411... https://en.wikipedia.org/wiki/Green_Revolution

In principal, I disagree conflating two different types of advice/goals like you are in your original comment (1. a statement about what is/is not healthy to eat, 2. what or what not is ecologically sound, made clear in your second comment to which I'm now replying) without making it clear that you are making that leap. The two goals may prescribe some contradictory action.

For example, lets pretend for a moment that the worst sort of ecologically disastrous forms of industrial farming happened to produce the most healthy and nutritious food; it's conceivable GMO could well spark that debate not unlike that. Do you make a single statement saying to eat good organic food to stay healthy without also making the statement you're compromising the health portion in balance with ecological concerns?

I think making a simple health statement without also being fully clear about also making an environment statement also erodes trust if found out.

You can remove the second reason and it's still just as valid. But that said, this kind of thinking is exactly the sort of problem we have when looking at complex systems. You can't examine any piece of it in isolation. Health is not isolated from environment.

In Mongolia people eat only meat from horses, sheep and camels. Mongolia is at the top charts regarding the dearth from heart deceases and cancers especially the liver cancer. And this is in a population that was exposed to this diet for thousands of years and where the meat comes from the most humanely treated animals.

One may argue that the statistics is biased towards people from cities where doctors have a better chance of diagnosing the causes of dearth and where people eat much more processed meat than in rural areas, but then the average lifespan in Mongolia has been increasing despite people moving to the cities. In addition there is a small population of ethnic Russian who moved to Mongolia 100 years ago after the revolution. They show the same patterns of deceases.

Disclaimer - I am vegan for ethical reasons.

Yet, somehow, Mongolians seem to have a slightly higher life expectancy than Indians, who generally subsist on plant-based diets.

Sounds like people with health issues over there are also living "harder" lives:

>"Cerebrovascular diseases, ischemic heart diseases, perinatal deaths, influenza/pneumonia/asthma and tuberculosis were the leading causes of AM in the past eight years in Mongolia. The AMR [amenable mortality rate] was higher in remote western provinces with harsh weather conditions, high poverty rates, lack of human resources for health, and poor infrastructure." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4767514/

It at least has the definite benefit of being less resource-intensive. If you accept the premise that we're just guessing what the right diet is, we may as well guess the "cheapest" option.

The paleo diet is based on a different guess: "As long as we're guessing we may as well guess the options most likely to be compatible with our evolutionary adaptations." This seems completely incompatible with picking the cheapest food, but healthier.

I'm not saying I agree with the premise (that we really have no idea what a healthy diet looks like), but given the situation where are all diets are equally likely to be healthy, picking a cheap one makes sense.

Yes, if we know nothing about food except for its price, it's reasonable to chose based on price. But do you really think that's true? There's no credible basis for selecting one food over another based on its nutrition?

I wonder if this is the point of much of the smoke blown into nutrition research by Big Food. People get so confused they think wtf, if the big brains can't figure it out, how am I supposed to. I'll just buy that, it's cheap and tasty.

Do I really think that the rational thing to do is always only eat the cheapest food? No, I don't. I was reacting to the premise, which is that all diet advice is as likely to be correct as any other. This is clearly a false premise.

This has nothing to do with resource consumption, it has to do with health/longevity.

Look at our teeth, mostly plant chewing teeth.

Yet our gut is optimized for a meat based diet. Our digestive system resembles more the one of lion than the one of our closest cousin - the chimpanzee.

In his book "Sapiens", Yuval Harari talks about how we literally drove into extinction something like 90% of the biggest animals on Earth. And that wasn't because we competed with them for the juiciest grass fields.

My teeth chew meat just fine. They wouldn't work so well as weapons, but humans devised tools for that purpose long ago.

Is that true? How do we determine that our teeth are primarily intended for eating plants?

> a healthy diet really can just be summed up as "eat food, not too much, mostly plants"

Absolutely not. We do know enough about malnutrition to say that this statement is false.

It has also been demonstrated that "zero carb" diets have all sorts of short-term desirable outcomes, such as weight loss or controlling diabetes. Your "don't eat too much, mostly plants" diet fails here.

What we don't know is the long-term outcomes of that (or any other) diet. Frankly, I'd rather risk a shorter life than continue a life of obesity, which is also associated with higher mortality.

"eat food, not too much, mostly plants" - you can't really generalize to that, as climate and lifestyle are very important too. Someone living in cold places might not even be able to survive on that advice.

Why not?

Because it can be very difficult to find affordable plant-based food in cold regions, especially if you're trying to make that food the majority of your diet.

People looking to derive most of their nutritional needs from plant-based food need various kinds of infrastructure around them if some or all of those plants can't be naturally grown nearby. Generally this means transporting them from a hospitable growing environment or making the local environment artificially hospitable.

You also need to eat a lot of food just to keep your body warm if you are exposed to cold a lot.

I think the only universally derided food is sugar.

And carbs is too big of a category. Basically food racism - declaration of a entire population of food as good or bad doesn’t help.


As a vegan who is constantly seeing anti-vegan (or pro-keto) sentiment on HN, it's nice to see a post about a Blue Zone[1].

Interestingly, the Okinawans eat a different sweet potato from the one shown. It's appropriately named the Okinawa sweet potato, and it's purple on the inside, due to having a high antioxidant content similar to blueberries[2].

These are not to be confused with sweet potatoes that are purple on the outside, and often confusingly called Asian sweet potatoes or Japanese sweet potatoes[3].

If you live near an Asian market, you should try looking for the Okinawa sweet potato (I get mine from a Chinese place near my home in LA). It has a very different taste and texture. I personally like to cut them up, steam them, and throw them into a food processor. They develop an interesting pasty texture which I quite like.

[1] https://en.wikipedia.org/wiki/Blue_Zone

[2] https://www.downtoearth.org/health/nutrition/okinawan-sweet-...

[3] https://paleoleap.com/wp-content/uploads/2013/12/japanese-sw...

Very interesting, thanks for sharing!

Your second link says that the Okinawan sweet potato is a staple in Hawaiian cuisine. I wonder if there were studies comparing the health profiles of Hawaiian and Okinawan people.

Do you have anymore recipes for them? I think I’ll stop at an Asian grocery today. But I live off easy recipes.

Honestly, I love sweet potatoes so much that I don't really use them in recipes, per se. I almost always just eat them as-is, completely on their own!

There was one time I made mini sweet potato pies with the Okinawa variety inside a muffin tin, and another time when I made a cheesecake (vegan) that incorporated them. Obviously not healthy, but it was the holidays, hah.

I think in general, tasting them on their own and figuring out what pairs well is your best bet. I think like "typical" (orange) sweet potatoes, they have that sweet-flavor-but-works-really-well-with-savory-foods property.

As for the Asian/Japanese variety: those are my absolute favorite, and I only ever eat them completely plain, on their own. I just cut them up, steam, and eat. So delicious, although I suspect they're not quite as nutritious as the orange variety, but it's usually hard to find information on less well-known cultivars.

Also! I should've mentioned this, but if anyone is searching for the Okinawa variety and can't find them, there's another purple sweet potato called the Stokes Purple sweet potato[1]. I have never seen them in person and have no idea how they taste, but I would bet they're not too different.

[1] https://www.friedas.com/stokes-purple-sweet-potato/

I eat loads of sweet potatoes but my favorite recipe is to put them in my curry. Sweet, salty, spicy.... It blows regular potatoes in curry away. I cook the purple ones hot rock style and eat hot or cold if it is summer.

Do you have a quick low mess way to steam them somehow?

I lucked out and my local grocery had Japanese sweet potatoes today.

No way in particular. I just have a steam basket for my big pot, which kinda looks like this: https://image.sportsmansguide.com/adimgs/l/2/231755_ts.jpg

I just throw in the pieces (about 1-2 bites each in terms of size). Sometimes I pile them up all the way to the top! They're pretty strong, so they don't get squished or anything. Cleanup is super easy.

Alternatively, boiling works just as well. I personally just find steaming to be faster (both in cooking and the retrieval of the food), it uses less water, and it eliminates the possibility of waterlogging them.

Blue Zones are not vegan though. The Sicilian one is basically people eating pizzas, pasta with cheese, fish.

Obviously not vegan. But, according to everything I've read, the so-called "Blue Zones" feature significantly fewer animal products in their diets than shorter-lived regions do in theirs. (And, Sicilians tend not to eat a lot of red meat, if I'm not mistaken. As far as animal products go, cheese and fish come with significantly less baggage in terms of health impacts.)

Highlights from the article, pertaining to the Okinawans' lifestyle and diet:

* little smoking among population

* strong social bonds → observed to be beneficial to bodily defence against stress

* high engagement in agriculture and fishing jobs → high physical activity

* possible effects of genetics — high presence of FOXO3 gene

* 10-to-1 carbs-to-protein comsumption ratio, like in other particularly-long-lived populations – linked studies support the conclusion, though too early to judge definitively

* sweet potato, rather than rice, is high-consumption food in the Okinawan diet

* most of the diet is vegetables and fruits; meats and fish are rare

* calorie consumption is, on average, 13% lower than general population

* it is suggested that past the age of 65, protein consumption should increase

* studies suggest that plant-based protein intake have a more positive effect on the human organism than meat- and fished-based

* their diet is not the "elixir of youth", as multiple interacting factors may be in play

The article mentions isolation leading to unique genetics but then ignores the obvious conclusion that the ideal diet for them is also unique to those genetics. We know there are different dietary adaptations in different populations why do we keep looking for the one trusted diet? That said the lack of stress in this population is almost certainly universally applicable.

Interesting, how can there be both a high engagement in fishing jobs and low amounts of fish in the diet. Are they very unsuccessful fishers? All the fish is sold to some other, by definition unhealthy, population?

Or, they don't report their elderly dead to collect their pension. There has been stories about this: https://www.bbc.com/news/world-asia-pacific-11258071

That would be funny: "High carb diets explain pension scams".

I suspect that staying slim and trim leads to longevity, regardless of diet, be it high carb or high fat.

+ Socially active and supported

> "Despite the popularity of the Atkins and Paleo diets, however, there is minimal evidence that high-protein diets really do bring about long-term benefits. So could the “Okinawan Ratio” – 10:1 carbohydrate to protein – instead be the secret to a long and healthy life?"

In the low-carb diet you are mostly replacing calories from carbs with calories from fat. Not sure why they are focused on this carb to protein ratio.

> "The traditional Okinawan diet is therefore dense in the essential vitamins and minerals - including anti-oxidants - but also low in calories.


For this reason, some scientists believe that Okinawans offer more evidence for the life-enhancing virtues of a “calorie restricted” diet."

Well, the benefit of low-carb is that you crave less food so naturally "calorie-restrict" relative to a high carb diet. So if they are accomplishing this another way it all makes sense (they mention some genetic factors in tfa).

Also, there's good food and there's bad food. It's hard to find something that you could label 'keto' that's downright terrible (once big food catches on I'm sure there's gonna be a ton of awful 'keto' food).

I spend a lot of time in Japan and US. In Japan food is simple, unprocessed, healthy. When I come to US and even though I eat well the food feels like glue in my stomach. And everything has horrible carbs in it. Salads? So much sugar I can barely eat them. Meat? Laced with sugar.

I wouldn't mind carbs from vegetables but they get mixed in this sugary garbage and then people come out and say "carbs are good for you" and then you end up fat and unhealthy.

Also, when I eat carbs I simply don't feel so good. Keto has been great so I'm going to stick to it.

I don't mind going off-keto but I won't touch anything with added sugar. Go to Whole Foods and look at kombucha. Why does it need a ton of sugar? It's hard to find one that doesn't. Or that "healthy" cucumber something something kale juice? Ton of sugar. Yuck.

Yea, a big confound with the keto stuff is you pretty much are forced to cook for yourself. Sugar is added to everything you can imagine, its ridiculous. Sugar used to be considered a spice/medicine...

>"There are records of knowledge of sugar among the ancient Greeks and Romans, but only as an imported medicine, and not as a food. For example, the Greek physician Dioscorides in the 1st century (AD) wrote: "There is a kind of coalesced honey called sakcharon [i.e. sugar] found in reeds in India and Eudaimon Arabia [i.e. Yemen[17]] similar in consistency to salt and brittle enough to be broken between the teeth like salt. It is good dissolved in water for the intestines and stomach, and [can be] taken as a drink to help [relieve] a painful bladder and kidneys."[18] Pliny the Elder, a 1st-century (AD) Roman, also described sugar as medicinal: "Sugar is made in Arabia as well, but Indian sugar is better. It is a kind of honey found in cane, white as gum, and it crunches between the teeth. It comes in lumps the size of a hazelnut. Sugar is used only for medical purposes."[19]" https://en.wikipedia.org/wiki/History_of_sugar

> Go to Whole Foods and look at kombucha. Why does it need a ton of sugar?

It needs to ferment in order to become Kombucha, which requires sugar.

While true it's a very grey area in how the sugar is reported. It's not clear whether they are reporting macronutrients pre or post fermentation. Ferementation in kombucha is particularly efficient from what I understand and the residual sugars after fermentation are not significant. So it's unclear whether the high carb count is due to sugars added pre-fermentation or if they are only including sugar added post fermentation to make it sweet.

There are too many with added sugar, presumably to make it "taste better" for sugar addicted populace. You can find some with low sugar content, generally ginger flavored.

But its the same with everything. Cucumber juice, watermelon juice, this and that, most bottled teas, etc. Sugar, sugar, sugar. Everywhere.

In Japan I can go to convenience store and buy dozens of drinks with no sugar.

Or electrolyte supplements. No sugar versions are much harder to find!

It needs to start with sugar, not necessarily end with it, for the same reason that most beers do not have sugar.

Bacon and other cured meats are technically keto but terrible for you.

That is just not true at all. The nitrates thing is far from proven (there is also uncured bacon available if it bothers you) and bacon itself is a high fat meat source that is very good for you.

Please tell me more.

“Studies have shown increased risks of colon, kidney, and stomach cancer among people with higher ingestion of water nitrate and higher meat intake compared with low intakes of both, a dietary pattern that results in increased NOC formation. Other studies have shown modest evidence that higher nitrate intake can increase the risk of thyroid cancer and ovarian cancer among women.”


Ah, slinging studies. Well it's a correlation. I did a lot of research on this and all I could conclude is that the science is still very unclear.

Nitrates/nitrites are also found in vegetables. Actually, from what I understand vegetables are one of the largest dietary sources of nitrates by far.

In fact, they can have some health benefits. From what I have found, the primary danger of nitrites comes when they go through high heat cooking. This is why nitrites/nitrates in vegetables isn't as big of a concern - you typically do not cook them at very high heat. So heating up bacon in the oven or even medium heat in a pan does not release nitrosamines in the same amount.

I'm not trying to sway you either way, just pointing out there are a lot of factors that study does not take into account and it's much more nuanced than a simple correlation.

From the The European Code Against Cancer:

"Avoid processed meat; limit red meat and foods high in salt." [1]

[1] https://cancer-code-europe.iarc.fr/index.php/en/

The world is breaking down into name calling and finger pointing. I'm surprised humans ever got out of the dark ages, hell I'm surprised that we stopped flinging poop at each other, well technically it is what is happening with the Internet and Social media.

Move to Okinawa, live their life and eat their way and lets see what happens.

Not everything works for everyone. I tried eating vegetarian for almost a year then I got stricter and switched to vegan for 6 months because being a vegetarian wasn't working for me. The worst 18 months of my life. I was eating a well balanced diet, watching vitamins and mineral intake, my hair started falling out, by skin looked horrible. I became a vegetarian because I was 75lbs overweight, with high blood pressure. When eating a calorie restricted vegetarian/vegan diet and lifting weights and doing cardio I managed to gain weight and my blood pressure never improved.

I switched to Keto, my hair recovered, my skin looks fantastic, I have energy I'm sleeping better, my job performance is much better, and without eating a calorie restricted diet I've lost 60lbs in 9 months and my blood pressure is normal, all without exercising. I'm now starting to lift weight again.

People are different. If you don't try to tell me that keto doesn't work for me I won't you that the Okinawian diet doesn't work for them, or that being a vegan/vegetarian doesn't work for you.

The ever changing field of diets must be the most shining example of the infinite need for people to come up with theories to justify their own quirky believes.

They buried the lede. It isn't a high carb diet, but a low calorie diet with 10:1 carb to protein ratio. A more accurate description would be "low protein" diet. While carbs might make up a higher proportion of their calories, in absolute terms it's definitely not a high carb diet.

To try and sell a high carbohydrate diet based on this isolated community is disingenuous. "They eat an abundance of green and yellow vegetables – such as the bitter melon – and various soy products. Although they do eat pork, fish and other meats, these are typically a small component of their overall consumption, which is mostly plant-based foods." In other words they eat a nutrient rich diet, not high carbohydrate as implied (They eat little rice which is high carbohydrate.) They are small in stature that implies an evolutionary response to food shortages. Questions I have are do they use "naturally" fermented soya? do they walk a lot? Alcohol? Interesting read even though I dont buy the titles narrative

There are important health differences between refined carbohydrates and carbohydrates that are naturally very high in dietary fiber like sweet potatoes.


Sure, refined carbohydrates (and sugar) are empty calories that are better avoided if you want to lose weight.

Foods rich in fiber like sweet potatoes, oatmeal, whole grains, peas, and beans contain carbohydrates, but are nonetheless healthy foods you should be eating.

> Genetic good fortune could be one important factor. Thanks to the geography of the islands, Okinawa’s populations have spent large chunks of their history in relative isolation, which may has given them a unique genetic profile. Preliminary studies suggest this may include a reduced prevalence of a gene variant – APOE4 – that appears to increase the risk of heart disease and Alzheimer’s.

Their high-carb diet has nothing to do with Okinawan longevity. Genes are the most important factor.

This article is ridiculous click-bait.

The use of "high-carb" is also misleading. As described in the article, the Okinawan diet is mostly vegetarian, and calorie-restricted, not really what comes to mind when you hear the phrase "high-carb," though it might be technically correct.

I downvoted you. The fact that the article raised the point shows they understand your point - baseless attack calling it click bait.

Do Okinawans who emigrate to, say, America show similar longevity?

Virtually all articles on longevity and diet are click bait.

Well, they do have evidence of Japanese emigrating to Hawaii and getting standard US health problems. Also when US fast food became popular in Okinawa the young people who ate it regularly developed US health problems. (Plenty of videos on YouTube about this as well as articles.)

It is about what you absorb instead of what you put in mouth.

Well, that's settled then. No need for data, I trust you.

Applications are open for YC Summer 2019

Guidelines | FAQ | Support | API | Security | Lists | Bookmarklet | Legal | Apply to YC | Contact