Ask HN: What is something important I should start doing in my 20s?

There are many important things you could do, but they have as much value as a helpful book in a library that you never visit...unless you practice them regularly.

Here are some things that may help your quality of life several decades from now.

Financial health:

* Start saving a large chunk of your income and invest it wisely in assets that will provide value over the long term. Avoid get rich quick schemes.

Physical health:

* Exercise everyday, preferably for a minimum of 30 minutes (it doesn't have to be a single session).

* Eat well, meaning, you can eat in tasty and highly indulgent foods, but develop the habit to eat more of whole and unprocessed/minimally processed foods.

* Related to the previous point, cooking is a life skill that will help manage your budget and health better. Learn to cook and try to cook at least one meal a day, if not all meals for the day.

* Sleep well and rest well during your waking hours.

Mental health:

* Related to the point about sleep and rest, try to regularly review your interactions online and offline, and cut off those that are not productive or those that make you feel worse, increase stress, etc. Good relationships can uplift you a lot, and bad relationships can make every other achievement pointless.

* Try out meditation, and if you're sure about your mental health, try a meditation retreat (even once is enough for a different perspective).

* It's natural to get extremely angry and upset about many things in this world. Practice some detachment if possible (this depends on your background and situation).

Odds and ends:

* Measure and track what you value. Without measurement, you won't realize how far you've reached or how far you've deviated from your desired states.

* Enjoy life through whatever provides you joy. Don't get guilt tripped by others on this front.

* Though related to health, I'm keeping this for the last since it may be very controversial. Avoid or drastically minimize the consumption of alcohol, smoking, and also caffeine if you can. The accumulated damage from these over decades cannot be reversed (well, if you have good genes, then it's a different matter).

I've seen a lot of extremely smart people in their early 20's. Young people can easily be as good as older people. The big difference is that respect, pay and responsibilities are hoarded at the top and not offered to juniors.

Totally agree. It is a trap to spend heaps when you earn a lot (compared to the average for your society). Living beyond your means can quickly become a compounding problem.

Hate to be that guy, but that's wrong.

Body weight is determined by calories in vs calories out. Eat less calories than you burn, body weight goes down, eat more, body weight goes up.

Body composition is determined by exercise and diet. Lift weights and get enough protein, muscle mass increases. Run marathons and don't get enough protein, muscle mass decreases.

In general, compound movements like squats, deadlifts, pullups, presses etc should be preferred over isolation movements like crunches. Crunches are kind of a pointless exercise, even for working out your abs.

Exercise! Can’t emphasize this enough! Makes you happier and healthier. Also a harder habit to adapt later in life.

Don’t do drugs, gamble, drink, or watch tons of porn.

Do read. Books. Not kindles. Books.

Be part of a regular community. That could be church, a sports team, chorus, etc.

Invest. Put money in an SP500 index fund. Especially if retirement accounts available.

Don’t be an asshole.

If you need therapy, get therapy. Take a Carnegie course. Even taking etiquette lessons can help.

Learn to cook. You’ll save so much money and eat much better food.

Get a pet. Having a pet is a lifestyle, and a good one.

Consider having kids. It’s rare people say “I wish I never had children.” Early 20s might be too early, but there’s no perfect time.

Also, have fun!