I've certainly seen a general drop in anxiety and effects of stress, other things being equal. I've had more than my fair share of stress during the past couple of years, and somehow come out feeling much happier and healthier and relaxed.
F 5 ft 3. HW: 196 lbs. Primal SW (May 2011): 182 lbs (42% BF)... W June '12: 160 lbs (29% BF) (UK size 12, US size 8). GW: ~24% BF - have ditched the scales til I fit into a pair of UK size 10 bootcut jeans. Currently aligning towards 'The Perfect Health Diet' having swapped some fat for potatoes.