I define health as-facilitating your ability/capacity to function. I see this everywhere from everyone, my whole life. I've also seen people who for many reasons have become incapable of this, it's almost felt as an animal instinct, by those around them, that these people are in real trouble of the kind that could be terminal. The current healthist definition of health is more like a form of hypochondria.
If you get to know anyone, they will tell you what they do to get all kinds of outcomes that lead to the former definition. They do this from their own experience, on the advice of people they know and respect, on instinct and on their own initiative. Often delivered with a preamble of 'you'll never guess what I do...' or 'you won't believe what's good for that...' etc.
Where they fall down the world over, is when the definition of health becomes an elitist game, set up to ensure nobody really wins. That is the healthist game. The rejection that so hurts fat healthists, some of which is the motivation for their involvement in fat acceptance-to be included into what's defined in this form of health-is just a more obvious manifestation of the truth of this form of health; no one can truly achieve it because it's not actually tangible.
Just as no one can really be a living saint. You might think Mother Teresa, but trust me, if you took a good look at her, you'll find the truth on that score.
No matter what you do there will be some reason why you are failing, or falling down, fat is just one of them. If it's not what you eat, it's what you don't eat, if it's not your level of exercise, it's your types of exercise, frequency variety, etc. If you become ill, it's because you lacked X, you can never be right. It's always an aim that you can never fulfil except possibly temporarily, in extremes of endeavour that hardly add up to an ideal of health.
Because everything is seen in their terms, our concern and deep desire to be part of our healing and well being is erased, just like fat people's desire to be well is in general.
We are told to believe that we don't care about our health, because our bodies don't want to and don't like what healthists tell us to do. Any system of health would take this feedback seriously and adjust, using it to inform and direct. But healthism doesn't want that, it wants you to do what it wants you to do, above all and doesn't like spontaneity or personal initiative. even when we try to force ourselves, what healthist define as healthful. We must remember that we don't have to answer to this definition of health, anymore than we have to answer to religious or political.
Health is only useful if it's useful to us, if we can benefit from it in ways that actually help and not hurt us.
We have that right, regardless of what anyone says.