|Seth Rogen at the low & high end of his schlub range.|
1. you're healthy otherwise,
2. your pants fit (pants cost money), and
3. your BMI (body mass index) is under 30 (calculate it here).
So relieved to find my gut feeling validated: being slightly schlubby (BMI between 25 and 30) has a protective effect in lowering risk of early death, according to some recent studies.
Reasons for the finding are unknown. One theory jibes with personal experience: that little extra fat is your friend when you're super-sick. To wit: We have a slender family member who doesn't get ill often but when it happens, it goes to 11. And the one time I was seriously underweight for about five minutes, I frequently got scary-sick, like think-you're-gonna-die time.
So as long as you're healthy and your clothes fit, don't get too skinny. You'll live longer.