Caffeine is a complex substance, its interaction with your body is going to have a personal element.

Some of its properties: it is a diuretic, a vitamin C inhibitor, it increases your blood pressure.

Anadin Extra is merely Anadin with added caffeine.

So you should treat it with appropriate measures. Just saying it affects sleep from its stimulation effects is not the whole story.

Your body has a daily cycle. I would contend that staying up after midnight creates more imbalance than not. "Early to bed, early to rise makes a man healthy, wealthy and wise" is not as glib a suggestion as it sounds.

I know from direct experience as my doctor told me "go to bed before midnight and throw away your alarm clock" and I've thanked him for it ever since.

Back to the coffee : I've experiemented with it on myself. My results are "no more than 1 litre fresh ground a day (about 30g of beans I think), all before 14:00hrs".

And if you want to lose weight, drink it right after meals.