Examine.com explains the different processes and advantages to our common tea options. As always their posts provide the scientific support references. My summary would be:

• Most Teas we drink are are derived from Camellia Sinesis (green, black, white, oolong and pu-erh).
• Catechins are flavonoids which carry the most of the health benefits
• White tea tends to be higher in catechins by weight, but when content is equal green tea has more anti-oxidant potential.

Overall, green tea is the ‘basic’ tea that is enzymatically inactive and non-oxidized. White tea and Oolong tea are partially oxidized, but Oolong is still enzymatically active. Black tea is fully oxidized and enzymatically active. Pu-erh tea is fermented and quite unique from the other teas.