r-ALA is meant to effectively convert the carbs in your system. Taken in the proper dosages, you should take it as needed with each meal (I don't use it on pre-bedtime meals as it's too low in carbs).
though certain categories will see extremely significant changes.. particularly older people (30+), women in menapause, people that are overweight, people that have type II diabetes (though there will be variances within this group).