Thought I’d post this in case anyone’s interested. I’ve been taking Ester-C which supposedly enhances absorption of Vitamin C and can’t find any significant studies confirming this but did read of one small study of vitamin C bioavailability in 8 women and 1 man which found no difference between Ester-C and commercially available ascorbic acid tablets with respect to absorption and excretion of vitamin C.

Now there’s PureWay-C http://www.innlabs.com/purewayc.html
Pubmed has a couple of interesting studies on it’s increased rate of absorption compared to ascorbic acid, calcium ascorbate and Ester-C, and its superior antioxidant capacity: http://www.ncbi.nlm.nih.gov/pubmed/17901843?ordinalpos=...anel.Pubmed_RVDocSum

Comparison between Ester-C and PureWay-C: http://www.ncbi.nlm.nih.gov/pubmed/17325628?ordinalpos=...anel.Pubmed_RVDocSum