Yes i agree beauty scientist, avoiding alcohol and caffeine is a good start and drinking plenty of water can be added to that list.
The liver is indeed a very good detox system but with the increased amount of toxins in our modern day lives in our shampoo,air, soaps, water and even in our clothes, other detox methods can be beneficial in giving the body a bit of a boost!
Raymond Francis, in his book, Never be Sick Again, states, "Saunas get your heart beating and your blood circulating, helping the body to detoxify in unique and important ways."
I really believe in using saunas to detox and always feel fantastic after a treatment or two : ) As for detox treatments for the skin, (or at least cleansing treatments), i suppose they are more a treat than a necessity! But they do help clean out the pores-detoxing the skin rather than the body as such.
Holly x