Over at The Heart Scan Blog, Dr. Davis has done your leg work on choosing the healthiest wine:
Wines rich in procyanidins provide several-fold more, such that a single glass can provide the same purported health benefit as several glasses of a procyanidin-poor wine. […]
The winner in procyanidin content is a variety grown in the Gers region of southwest France, a region with superior longevity of its residents. The wines here are made with the tannat grape within the Madiran appellation; wines labeled “Madiran” must contain 40% or more tannat to be so labeled.