I don't see what there is to sneer at, it's just common sense. There is too much obesity and too little exercise, not the other way around, that's why so much is said about the unfit and obese bankrupting the NHS before much longer. I despair at how fast I've been going down the plughole since my heart forced me to stop cycling. It's exasperating to watch those who could exercise but don't, when I want to exercise but can't, especially when I keep getting told that there's no reason not to exercise.
Regarding smugness, you only need to watch healthy eating threads on the internet to see that many are not about healthy eating at all. They quickly morph into cookery threads, full of gourmets crowing about how their diet must be healthy because they cook it all from scratch.
Perhaps anyone who thinks he really can't spell psychology should consider all those who refer to reading, 'riting and 'rithmetic as the three Rs.