Yogurts labelled UHT, pasteurized, or long-life has been heat-treated after manufacture to give a long-shelf life and stability at room temperature. This process kills the bacteria. The effect on lactose digestion will disappear.
Fresh yogurt contains about 100 millions live bacteria per gram of yogurt.
Source: The First Global Summit on the Health Effects of Yogurt 2013, Experimental Biology meeting in Boston, USA, on 24 April 2013.
