Well I watched the programme. The major weaknesses of such enterprises are the tiny samples of people involved and the necessary briefness and superficiality of the methodology. Very little real science came out of the programme, though the section on depression was nicely done and the work on pigments and eyesight was definitely enough to provoke further study. As for gluten, all I can say is that a few weeks ago I had to cook a pasta dish for the twelve ladies of Mrs Steve's dancing class. One of the ladies was gluten-free so I had to buy a bag of free-from pasta and make a separate batch for her. As any pasta chef will tell you, you have to taste the pasta constantly to get it to the perfect al dente condition. Well I can tell you that gluten-free pasta tastes nothing at all like the real McCoy. I can't believe that the volunteers who had had gluten-free pasta sneaked into their diet didn't spot it.