[Aboutplants]

My doctor always says “There are three little things that will give you the best chance at living a long and healthy life. Eat a little better, move around a little bit, and get a little more sleep”

[jeremyjh]

Its even better to have a government pension that sends checks to your address as long as you are alive.

[PaulDavisThe1st]

For the statistics though, it's even better if those checks continue after your death.

[adventured]

Eat fewer calories. Consume as little added sugar as possible.

You don't have to eat much better. You can trivially supplement. It's far more important to eat less.

[loeg]

This is basically not true. The particular makeup of the calories you're consuming matters. E.g., it is likely (but not proven) that dietary fiber is causal for reducing rates of common cancers. And also likely that dietary saturated fats cause various kinds of heart and artery disease. Similarly protein is important for muscle mass which is associated with longevity. Additionally, people who are already underweight should not reduce their calorie consumption.

[HerbManic]

Alas, the easiest advice is the hardest to follow short term but the best to do long term.