
Ask HN: Is there any evidence in favor of or against ketogenic diet? - gnulinux
21, male, exercise regularly, healthy. I live in a friends circle with a lot of bodybuilders, eating 0 carb, high pro, high fat diet. I tried reducing my carb intake. I felt generally good, but nothing significant. I was skeptical to continue this any longer than a month or so because when I did some research on keto it seemed like there is almost no long-term study supporting keto for healthy humans. I found some evidence for unhealthy people: [1], [2], [7].<p>When I searched about people who support this diet I found two interesting things. For one, these people (as seen in this [3] reddit thread) are convinced that modern society likes the taste of carbs and feel &quot;safe&quot; eating plants, so people don&#x27;t want to spend money on researching keto diet (as seen in that thread). I&#x27;m skeptical of this since research institutes do research on things public is not generally interested in.<p>Second, proponents of this diet seem to think this diet is practiced by ancient humans before agriculture. Recall the contents of Iceman Otzi&#x27;s stomach before he was murdered [4]: fatty goat meat and pure fat (lard). We, HN, recently discussed the lifespan and general health of our ancestors. [5]<p>There is also this [6] research paper:<p>&gt; A low-carbohydrate diet based on animal sources was associated with higher all-cause mortality in both men and women, whereas a vegetable-based low-carbohydrate diet was associated with lower all-cause and cardiovascular disease mortality rates.<p>[1]: https:&#x2F;&#x2F;www.ncbi.nlm.nih.gov&#x2F;pubmed&#x2F;27060389<p>[2]: https:&#x2F;&#x2F;www.ncbi.nlm.nih.gov&#x2F;pubmed&#x2F;24386671<p>[3]: https:&#x2F;&#x2F;www.reddit.com&#x2F;r&#x2F;ketoscience&#x2F;comments&#x2F;7o54yh&#x2F;longterm_keto_study&#x2F;<p>[4]: https:&#x2F;&#x2F;news.nationalgeographic.com&#x2F;news&#x2F;2011&#x2F;06&#x2F;110623-iceman-mummy-otzi-meal-goat-stomach-science&#x2F;<p>[5]: https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=18132096<p>[6]: https:&#x2F;&#x2F;www.ncbi.nlm.nih.gov&#x2F;pmc&#x2F;articles&#x2F;PMC2989112&#x2F;<p>[7]: https:&#x2F;&#x2F;www.ncbi.nlm.nih.gov&#x2F;pmc&#x2F;articles&#x2F;PMC2716748&#x2F;
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ajaxaddicted
[6]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2989112/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2989112/)
is a questionnaire, meaning the study design is flawed from the start. What
you are looking for is double-blind, placebo-controlled randomized studies,
not funded by the meat, egg or diary industry. For example, you can take a
look at these studies here
[https://www.ncbi.nlm.nih.gov/pubmed/?term=Fung%20TT[Author]&...](https://www.ncbi.nlm.nih.gov/pubmed/?term=Fung%20TT\[Author\]&cauthor=true&cauthor_uid=20820038)

Iceman Otzi had an artherosclerosis, not the best example of good health
[https://www.livescience.com/62689-otzi-iceman-mummy-heart-
di...](https://www.livescience.com/62689-otzi-iceman-mummy-heart-disease.html)

[7]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2716748/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2716748/)
is only 24 week period, following obese patients, which already have extremely
high levels of LDL by default. First of all - 24 weeks is not that long of a
period, second - if you just put obese people on any kind of diet that
restricts calories or reduces the amount of processed foods they eat - it is
only natural that they LDL will be lowered as a result

You can also take a look at this compilation of health studies:
[https://docs.google.com/spreadsheets/d/1cOFTFhMg1UakqvP5MGe6...](https://docs.google.com/spreadsheets/d/1cOFTFhMg1UakqvP5MGe6p0w75SbQWuJM32SBHZrw0Q4/htmlview#)

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tjr
I have made a few attempts at eating more ketogenic style in the past year,
reading some things that seemed promising. Anecdotally, I found it
inordinately difficult to stay that low-carb for very long; it seemed
especially difficult to stay low-carb and also restrict calories (aiming for
some weight loss on this end); I seemed to feel physically less healthy eating
that way than I do favoring more of a vegetable / beans / lean-meats diet.

So I have, at least for now, given up on that.

As far as evidence... really not sure what to say. For anything I found
supporting ketogenic eating, I could find something else that did not support
it. So many conflicting "nutritional science" reports that I'm really not sure
who to believe, and thus, for me personally, I'm more inclined to go with
whatever reports seem to best mesh with my anecdotal personal results.

I do notice that pretty much every credible-sounding diet plan advocates for
less processed sugar and less heavily processed grains, so that much should be
easy.

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protonimitate
My opinion has always been, balanced is best.

If you have to stick to a 'high' anything diet, make it vegetables.

I practice semi-Keto. But it works for me. I have a hard time controlling my
self when it comes to eating/snacking. I find that high protein/high fat foods
are more filling per calorie and stops me from devouring high carb snacks.

I think people get turned on by the near-instant weight drop when you cut out
carbs from your diet and lose water weight in the first few days.

Keto is also expensive and harder to stick to exactly than I'm willing to put
in the effort for. I supplement 'no carbs' with 'some carbs' from whole
grains, beans, and veggie-carbs to help bring down the cost.

The healthiest thing to do (imo) is to a) not over-eat, b) avoid added sugar,
c) get your micro nutrients, d) mix it up

~~~
gnulinux
My personal and limited experience also has been low-sugar, mid-carb, high-
fiber (lots of broccoli), high-protein, high-fat diet seems to make me _feel_
better. Although, it goes without saying, feeling better isn't isomorphic to
being healthy, living longer, or maximizing your bodily functions (such as
muscle building, better cognition or better sex life).

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Nomentatus
If you have an autoinflammatory disease (of which there are many) then
absolutely anything that lowers blood sugar and slows you down will improve
your symptoms for the simple reason that your body doesn't have quite as much
spare energy to attack itself. But you're still deliberately making life
difficult your body, so a shorter lifespan isn't too surprising.

Vert short periods of ketogenesis are a different story entirely.

[mouse study] [https://www.salk.edu/news-release/eating-in-10-hour-
window-c...](https://www.salk.edu/news-release/eating-in-10-hour-window-can-
override-disease-causing-genetic-defects-nurture-health/)

~~~
gnulinux
I'm not following you? The paper I gave can equally suggest longer lifespan,
or it can suggest animal-based diet causes shorter lifespan. Also anecdotal
evidence seems to suggest keto gives people more energy, not less unlike what
you suggested, and I'm struggling to find any paper supporting these claims
(both yours and anecdotal reddit evidence)?

~~~
Nomentatus
With a serious inflammatory disease, you'll have more energy if your body
tones down the cytokines than the little energy you had before; but not normal
energy because you've got 30% less blood sugar to play with. People in normal
health do less under a ketogenic diet, as one would expect.

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sethryclaus
Eating too much protein and not drinking enough water seem to cause more
problems on keto than standard diets.

You must read about ketoacidosis as that seems to easily be the most dangerous
risk. Diabetes is the main trigger for this.

The distinction between MCT (coconut essentially) and LCT based keto is very
significant - especially since the MCT diet can be pretty much vegetarian.

I've gotten a lot of mileage out of assessing other things on their own merits
and by their own rules since the majority of nutrition isn't about macros. For
example, eggs can become a bigger part of your diet on keto so it's important
to research eggs - which in my case resulted in salmon as a source of omega 3.

I don't have any difficulties staying on keto but I'm also a good cook and
every supermarket in my country is more like Whole Foods than a normal US
supermarket, according to friends who have been there (I have no idea what
they're talking about).

Finally, checking citations of various articles both for and against has just
lead me to ignore anything other than papers (and even then with a grain of
salt - @ajaxaddicted's sheet is a cool way of doing it).

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jonny_storm
The real question is whether or not ketogenic diet is good _for you_.
Unfortunately, the literature simply cannot supply a clear answer either way.

Joe Rogen just did a great show with two scientists discussing the evidence
for and against carnivore vs. ketogenic vs. low carb. vs. high carb:
[https://youtu.be/u93oh9kC-rU](https://youtu.be/u93oh9kC-rU). In summary,
we're a long way off from matching an individual's biomarkers to an optimal
diet, but caloric restriction seems to provide the bulk of the benefits for
any given diet.

~~~
gnulinux
I'm sorry I want to make myself clear that I'm a lay person so I'm not trying
to be skeptical. But is this correct? This conflicts with my understanding.
E.g. I have a family history of heart diseases (although mine and my sister's
hearts are healthy so far) so proponents of high-carb diet would claim fat
would increase the likelihood of heart disease by clogging my arteries. But
low-carb people would claim fat would have no affect on my arteries, and the
only factor would be my genetic markers making heart diseases more likely. I
would guess that if this debate was settled, wouldn't it be easy to just say
keto is bad since it increases the likelihood of heart diseases. But I really
cannot find evidence supporting this. Quite the contrary, plant based low carb
diet seems to decrease these diseases. What's going on here?

Even if you were to personalize my diet based on my full history and genetics,
it doesn't seem possible you could do that, since we don't have evidence even
for that.

~~~
DoreenMichele
As best I can tell, the comment is accurate and asserts three things:

1\. It depends a lot on individual factors.

2\. What we know is limited.

3\. Caloric restriction seems helpful, regardless of what you actually eat.

I haven't really looked at keto. What I can tell you is that different fats
have different chemical composition and this impacts how the body reacts to
them, especially if you have specific problems.

I have no plans to ever get all that knowledgeable about keto. I don't think
it actually makes sense and I suspect its positive reputation is probably
rooted in benefits from confounding factors that haven't been identified, such
as inadvertently eliminating allergens for some people. If you stop eating
things that are actively making you low grade sick, you will feel better,
possibly dramatically so, and it almost doesn't matter what you actually are
eating, so long as it is less harmful than what you were consuming.

~~~
jonny_storm
"...inadvertently eliminating allergens..."

Whatever your view on ketosis, I strongly agree that food allergies may be
causing more grief than we know. In particular, I suspect most people with
GERD are consuming food they're allergic to. It's tragic.

