I'm 34. I never had health insurance, my entire life, until last year.
If you go without insurance, do not call 911, go to the emergency room, or check into a hospital unless you're dying. They charge absolutely obscene prices when you are uninsured -- often 10x what they charge insurance companies. Of course this means you can negotiate down quite a bit. But you are still gonna get reamed, every day in the hospital extra for observation is at least a couple thousand, another couple thousand for the ambulance ride, a hundred bucks for every valium they give you to keep you calm, etc.
Of course you find out none of that until the bills start rolling in a few weeks later. And if you ask in the hospital, nobody knows what the prices for anything is. It's just "the doctor ordered it, swallow this". You have to always be alert, ask questions, don't let them blow you off if you really need an answer to something. Blah blah. And that's just to come out only costing 1 arm and leg instead of all of them.
Like I said, I went without health insurance my whole life as well, only been to a doctor a couple times. I didn't even get vaccinated when I was a kid (religious parents). So I can relate.
Honestly, if you're in decent health, at age 31 I wouldn't be too scared of not having health insurance. Yeah your life will go to total shit if something bad happens like appendicitis. You will have to go to a hospital, get an appendectomy (or you WILL die), and your net worth will suddenly be reduced by $10k-$20k probably. If you're at zero or below net worth like much of the population, this can ruin your life. Bankruptcy is getting harder for medical debt but I think it's still an option though.
Anyway. Grim discussion. BUT. If I were you, (and I was 3 years ago basically, except now there is the ACA), I would not get insurance yet and pay the fine ($95 or 1% of your income, whichever is higher, this year I think -- so 1% of your income if you have any income at all essentially).
However I was offered a job with the State of California last year, so now I pay $65/month for my healthcare. Although my employer pays $400/mo, and that is money they can't pay me, so it's part of the cost of having me as an employee, so I guess it's really costing me the $500/month anyway. Just like your employer has to pay 7.6% for fica or whatever same as you, so its really 15% (and if you're self employed you have to pay the full 15%). So either way its 15% tax you're paying, it's just which side it's listed on your paystub but it still could have been your money. :(