Obesity does not imply inactivity, though there is some correlation. From the article:

> Obesity and inactivity often go hand in hand. > > However, it is known that thin people have a higher risk of health problems if they are inactive. And obese people who exercise are in better health than those that do not.

And further down:

> "The greatest risk [of an early death] was in those classed inactive, and that was consistent in normal weight, overweight and obese people," one of the researchers, Prof Ulf Ekelund told BBC News. > > He said eliminating inactivity in Europe would cut mortality rates by nearly 7.5%, or 676,000 deaths, but eliminating obesity would cut rates by just 3.6%.

So the point is that irrespective of your weight, within your weight class you will be less likely to be healthy if you are inactive.

Exercising more may help you cut weight, but chances are that unless you specifically want to use it as an aid to cut weight you are likely to eat more to compensate for increased hunger. As such increased activity is by no means likely to drastically reduce obesity, but it can still reduce mortality.

> I would say obesity implies inactivity

It most definitely does not.

You can be obese and active if your body weight setpoint is off - after activity you are simply very hungry and eat.

The two things have some overlap but one does not imply the other in either direction.

There is surely a correlation, which I would think was what (s)he was implying.

Body weight "set point"? What's that?

The body has a desired weight built into it.

If you go over that weight it starts burning extra calories via thermogenesis, not absorbing as much, and making you not hungry.

If you go under it reduces thermogenesis, digests more efficiently and makes you hungry.

To try to change your weight you have to fight a VERY powerful feedback loop in the body.

Right, I thought thats what you were talking about. It's only a theory, and it's not that well supported in the literature[1]. Even presupposing it's true, the literature shows that it can be changed -- you're not stuck for it for life[0]. The issue I have with set-point theory are rather numerous, to be perfectly honest, but the key part is that it's used by some to "give up" and assume that being obese is "natural", which considering the massive negative effects it has on your body, doesn't sit right with me.

I'm happy to be proven wrong, but all of the research I've read on it shows that for the most part it's not a given that it's a real phenomenon. Human nutrition and metabolism is super complex, for sure, but those sorts of twee "too easy" explanations are rarely correct.

[0] http://jn.nutrition.org/content/127/9/1875S.short [1] http://www.fasebj.org/content/4/15/3310.short

I didn't say it can't be changed, just that it's very very difficult.

> but the key part is that it's used by some to "give up" and assume that being obese is "natural"

You are not born with any particular set point, you gain one based on your life (although there are tendencies). But once you have it, it's very hard to change.

I think of it like hysteresis - you need to work extra hard to get past it, but then it settles on a new value.

> I'm happy to be proven wrong

My personal experience of trying to change my weight for a full year, all sorts of methods, and eventually gave up for a while and one day weighed myself just to see how I ended up: The exact, to the 1/5 of a pound! weight I started with a year ago!

So I'm quite certain it's real, and yes, I'm giving up - somewhat.

I agree. Article makes it sound as if inactivity causes poor health (which it may). Alternatively inactivity maybe is just an indicator of poor health and not the dirct cause.