Separately from this study, here's an interesting opinion piece by John Ioannidis titled "The Challenge of Reforming Nutritional Epidemiologic Research", published in JAMA 2018:

https://statmodeling.stat.columbia.edu/wp-content/uploads/20...

  > Assuming the meta-analyzed evidence from cohort
  > studies represents life span–long causal associations, for
  > a baseline life expectancy of 80 years, eating 12 hazelnuts
  > daily (1 oz) would prolong life by 12 years (ie, 1 year per
  > hazelnut), drinking 3 cups of coffee daily would achieve
  > a similar gain of 12 extra years, and eating a single man-
  > darin orange daily (80 g) would add 5 years of life. Con-
  > versely, consuming 1 egg daily would reduce life expec-
  > tancy by 6 years, and eating 2 slices of bacon (30 g) daily
  > would shorten life by a decade, an effect worse than
  > smoking. Could these results possibly be true?

via Andrew Gelman's blog: https://statmodeling.stat.columbia.edu/2019/01/26/article-po...

Good thing I drink hazelnut coffee while eating eggs and bacon! It cancels out right?

You're joking, but that's probably the right strategy: make sure to enjoy things on both sides of the aisle, so you don't have to worry about which side adds, and which removes, years. And then don't fret about it.

Aside from that, I'd love to know how each of those items affects life quality. Living long is only a life goal up to a certain age, and from what I've seen around me, that age is very rarely 90.

Yeah, living to old age at the cost of overoptimizing every little thing in your life does not seem like a worthwhile endeavor. You'll only add years that won't be terribly useful or pleasant anyway, because anyone has to deal with some form of wear and tear regardless. At the very least, all the old people I know have to deal with some audition and sight loss, and even when they are in decent physical shape, they seem to be hurting somewhere.

It feels like trying to be immortal, which is a bit of a folly.

Anyway, the other day I noticed that Warren Buffett is just retiring at the age of 94. The man has eaten McDonald's for breakfast for much of his life. Diet cannot be that big of a deal.

What those epidemiological studies reveal is that food associated with higher class makes you live longer, which is reverse causation, at best.

I assume these needs to be indications on overall diet.

Edit: i.e a bacon eater consumes a higher than average caloric intake, hazelnut eaters have more greens/vegetables in their diet possibly

I would generally recommend ignoring observational nutrition studies like this one. There's just a massive amount of bunk science in that area. Correlations all over the place, very little evidence for causation.

Data point: my nutrition coach says I can eat up to 18 eggs a week no problem. She recommends two per day.

It's well-known that schizophrenics self-medicate with coffee and nicotine: https://en.wikipedia.org/wiki/Schizophrenia_and_tobacco_smok...

The inverse possibility--that nicotine, and perhaps caffeine as well, heighten the risk of psychosis in those genetially predisposed--has also been considered.

Not diagnosed, but eventually I noticed how veggies gave me psychotic episodes that would last for a few days. Was connected to oxolates seemingly. After one week of probiotics psychosis doesn't happen when I eat veggies now.

Incidentally caffeine calms me down as well.

Thanks for sharing your experience That sounds really unsettling to go through. I’m glad things have improved for you, but episodes that feel psychotic can be important to look into, since there can be many possible causes, not all of them related to food. If you ever feel comfortable doing so, talking with a medical professional could help make sure nothing else is going on in the background. Everyone’s body is different, and you know your experience best. I just hope you can get clarity and support so things keep moving in a good direction.

Could you share your probiotic regime please? What worked for you?

Yeah it's an interesting discussion whether schizophrenia causes smoking, or smoking ease schizophrenia, or smoking worsen schizophrenia, or they just often go together for whatever reason (maybe genetics) https://slatestarcodex.com/2016/01/11/schizophrenia-no-smoki....

No, it affects everybody. Says so in the article. The distinction appears to be that severe mental illness is associated with shortened lifespan so coffee has a more profound anti-aging affect on that population.

Interesting. I wonder if that extends to any stimulant, or if it's something particular with caffeine and coffee.

With that said, the fact that the other study seemed to find the opposite conclusion concerns me.

What other studies?

Studies of larger populations yield more typical results. Consequently, studies of smaller populations yield more extreme results.

That's not to say that these results might not be significant -- what you propose may be the case -- but I'd want to see an actual mechanism of action before buying something like this.

> I only did a postgraduate degree

This confuses me. Aren't all the best degrees postgraduate degrees?

Idk about the op study, but I could imagine confounders with instant coffee consumption.

True, and it could also be what the person has with the coffee. I have a feeling people that drink instant coffee are more likely to add milk, creamer, or sugar.

That said, instant coffee is just freeze-dried coffee. There's a possibility its effect is no different.

I think it’s typically a different species (Coffea canephora). So theoretically drinking bean tea of a different plant could have different health impacts.

Also known as Robusta. I have two different instant coffees at home and just checked - one is robusta, one arabica.