Morning Scepticism: Boost

One thing I often hear about herbal and vitamin supplements is that they "boost" the immune system. Though I'm not really sure what that actually means. Do they facilitate the increased production of cells? Do they help in the formation of the right antibodies? While I applaud the marketing technique, I can't help but think it's about as useful to "boost" the immune system as it is to "cleanse" the ear canal by listening to some Mozart every once in a while.