Lots of people have written good stuff in response to fat acceptance (or fat advocacy, or "for gods' sakes stop vilifying fat people" - whatever you want to call it) concern trolls - those people who respond with "But OMG you're GOING TO DIE". Fat Heffalump is the one that springs to mind right now, but you'll find it popping up all over FA stuff. I'm not going to repeat it, just pull out one aspect that runs through most of it - that you have no obligation to be healthy.
Concern trolls pull out "Your lifestyle isn't healthy" as though it's a lay down misere. Aside from the fact that it may not be true, even if it is, who says I have to be healthy? I may not even have a choice. For whatever reasons, living the troll's sanctioned "healthy lifestyle" may be entirely beyond my reach. Or living it might not, in fact, make me healthy. Or, I may have all the choice in the world, and decide that I value my current lifestyle more than health. Trolly McTrollpants has no right to decide that I should.
I've read this argument again and again, and I agree with it. But. You knew there was a "but" coming didn't you? There has always been something niggling in the back of my brain, a little "but" bouncing up and down behind the logic. When I finally paid it some attention, I realised it's not really so much a "but", rather it's more of an "also", or an "even so".
Before I even address the niggle, I need to point out I'm thinking in terms of "as healthy as one can be" not healthy by some arbitrary standard. I'm also including emotional and psychological health in this picture. Blood pressure is neither more important than, nor independent of, emotional and psychological well-being. Using a complete picture of health pretty much rules out fat shaming all by itself (nobody is healthy when they are made to hate their own body).
There are two aspects to this niggle, a personal and a public. The personal is straightforward - I think we do owe optimised health to those we care about. I don't think this negates the "no obligation to be healthy" as such, because I certainly owe nothing to Trolly, and because this is about balancing what you have, not meeting an arbitrary standard. My "optimised health" looks nothing like yours, and so making sweeping statements about how people should live isn't helpful. But I do think I owe my kids, my partner, and everyone I love the best health I can offer them, within the power that I have. That doesn't make ill-health a Bad Thing. It just means I should control what I can, and deal with what I can't.
The public is much messier. I proceed here with caution, but I don't think I can ignore it as an issue. In a country like Australia where health care is largely publicly funded, my decision not to be healthy has impacts beyond my immediate circle. Of course, if I choose to be fatally unhealthy in a swift fashion, it doesn't cost the country much (see personal obligations), but it is possible that lower grade unhealthy living costs the country money (although I'm not sure it's entirely clear whether health costs are going up because of healthy or unhealthy lifestyles - living longer can also cost more in the long run, and I've never really seen convincing arguments on either side). Assuming it does cost, what exactly does that mean for personal obligation to health?
I'll consider first the individual obligation (under the assumption that it does cost money). I'm struggling a bit with this, so I'm more than open to feed back and outright disagreement - I think it counts as one aspect of my membership in society. One thing I can do to contribute to society is to optimise my health. This does not include health issues over which I have no control, that is contribution neutral. On the other hand, there are many other ways in which I can contribute to society, and I think choosing to be something of a burden on society healthwise can be compensated for by my many other contributions. I have been a burden on society in myriad ways all my life, starting with my childhood and education and carrying on through my use of roads and other public facilities. I give back to compensate for that. This is true for everyone, and no-one gets to look from afar and judge a person's overall contributions.
That's the theoretical. From a practical perspective, we have no problems at all accepting and even celebrating other people damaging their health - elite athletes, mountaineers and other extreme adventurers, for example. It is outright hypocrisy to condemn people for, for example, sedentary related ill-health while celebrating sport related ill-health. I think all people have the same, vague and flexible obligation to be as healthy as they can, and all people have the same right to prioritise that obligation as they wish against other obligations and contributions.
When talking about costs to the public, the government's role obviously also needs to be considered. Still under the assumption that less-than-optimised health costs money, the government has an obligation to encourage people to optimise their health, as responsible custodians of the public purse. Note that their obligation is limited to encouragement, not requirement. People within a society make a million decisions every day that affect the people around them. On the whole we need to minimise the number of things which are enforced by law, and encourage voluntary, cooperative behaviour. So I support government initiatives that encourage health. Things which inform, things which make healthy options (food, activity, medication etc) more accessible, things which discourage behaviour that impacts negatively on other people's health (for example unhealthy work places, polluting industries and so on).
I do not support things which shame anyone for their health, whether they have control over that health or not. For starters, it's self-defeating. Shaming people damages their emotional and psychological health, and makes them less likely to participate - either in healthy activities or in alternative ways to contribute. Shaming makes them less healthy and less likely to contribute. It's also putting a moral rub on something that in fact only has a financial motive. The government has an obligation to be a good steward of our cash, it does not have the right to add moral overtones to that stewardship.
In the end, I have no strict obligation to be healthy, but I count optimising my health among the worthy goals that I can consider and that the government can encourage. There may be other worthy goals that I may choose to pursue instead, and that doesn't make me a bad person.