I was going to say 'everything in moderation' but Molbarre beat me to it.
Well, moderation in everything except guitar playing!!
Actually, that needs moderation too. No use in playing all day, non-stop and then wondering why you fingers/arm/shoulder etc are worn out or numb!
On a more serious note, health tips are usually relevant to things we (most people) don't do enough of. But if you do them already then they aren't relevant.
e.g. Drink 2 litres approx per day but if you do it already then it's not relevant.
But in this age of office and computer work, exercising and standing up more is quite relevant.
Also, weight training, and I think body-weight counts as well (e.g. squats/press-ups), is useful to keep us fit into old age because it strengthens our joints and bones.
I've read that our bones weaken as we age so this kind of exercise is apparently good and shouldn't be neglected.
But this just echos others comments regarding exercise