Why will Gatorade help with supply?

Hi,

I've breastfeed successfully for 3 years with my first and my new little boy is now 3 months. I've not changed my diet (I've been very ill both times and almost hospitalised, yet still produced milk) and I only drink when quench my thirst. Yet, I see here all the time to drink body armour and gatorade (yet I've no real idea what they are, I'm from the UK) - why do they work to boost supply?

Women in non economically advanced countries manage to feed babies on very basic diets. Yet in the west we are convinced that diet will help us produce more?

Plus, if you are exclusively latching, how can you even tell if you are producing more?

Thanks!