As much as I would love to claim myself as the perfect shining example of health, I usually have to say "well, it's more complicated than that." (Most people who know me now realize they will not get a yes or no answer out of me, and some of them even appreciate it! They also realize I'm no more perfect than anyone else). I did come across this blog post in the NYT the other day, however, that does give a pretty good overview of what we do and do not know about gluten, and who is and who is not taking a scientific approach.
We do know that people with true celiac disease do need to avoid gluten if they ever hope to recover a functioning digestive system. People with conditions like dermatitis herpetiformis also must avoid all sources of gluten if they ever want that rash to go away. That's a definite "yes, it's healthier" for people with these conditions. But for some of us it gets a bit murkier. There are no good tests for gluten sensitivity like there are for celiac disease (and even then, people have to make sure they have been on their regular gluten-full diet for at least two weeks for those tests to be accurate). And sometimes people feel better and lose weight when they "gluten-free" simply because their diets got healthier overall. I remember one patient who came to me with dermatitis herpetiformis who did lose about 25-30 pounds after he cut out gluten (he was glad to lose the weight), but since he didn't want to pay for the more expensive gluten free pastas, etc he wound up eating grilled/baked meats, more vegetables, and the occaisional rice/corn tortillas to fill in the gaps. In other words--he had a significant calorie reduction and he started eating higher quality food and found it satisfying. Had he been willing to spend the money on gluten free bread, gluten free pasta, gluten free crackers, etc, I highly doubt he would have seen an improvement. So, if someone winds up cutting out gluten and loses weight, and oh-by-the way I cut way back on my carbohydrate intake and eat more nutrient dense vegetables, maybe it wasn't the gluten.
One of the double blind studies indicated that a gluten free diet seemed to help people with irritable bowel syndrome. (IBS) But, it may not have been the gluten that causes the problems, there are other things found in wheat, namely fructans, that some people have trouble digesting and may cause symptoms. And with the people who claim relief of arthritis when eliminating wheat; once again we only have anecdotal evidence. If someon with arthritis wants to eliminate wheat, and subsequently improves the quality of their diet in other ways, and has a relief of symptoms--if it isn't broken I won't try to fix it, but I can't claim proof at this point.
Now, for those of who do have gastro-intestinal problems like the ones mentioned in the IBS article, please tell your doc so that you can be tested for serious conditions like celiac. If you and your doc do think your GI problems are diet related, the best approach that we have is to follow the Low FODMOPS plan. This particular plan severely limits foods that contain compounds that are poorly absorbed by the body, draw more water into the bowel, and cause "gas" through increased fermntation. You get to follow this diet for 6-8 weeks (hopefully with the help of a qualified person like yours truly!) and see if your symptoms improve. At the end of the six weeks you start adding certain things back in (one at a time!) and see if your symptoms worsen.
One of the other complaints about gluten free diets (besides the expense of gluten free crackers, etc) is that some health care professionals are worried about nutrition deficiencies. I understand their concern--because some people who are eating a lot of processed food just keep eating their processed food, only now they don't even have a little vitamin fortification from whole wheat bread, etc. You have to not just go gluten-free, you actually have to make sure your are getting enough nutrient dense vegetables, protein, and good fat. I also know that some people think that since not all people have genetically adapted to have gluten in our diet that no one should eat it--this sounds like it's based on an assumption that we have stopped evolving/adapting over the past 10,000 years and that doesn't appear to be the case either as some people do seem to be able to eat dairy and grains without an issue.
Take home message--If you have GI complaints and/or a weird rash that won't go away, talk to your doctor about the possibility of getting tested for celiac disease (particularly if these are in your family history). If all other problems are ruled out and your doc labels you with IBS, you can try an elimination diet to see if your symptoms improve. If you know you are overeating on bread, pasta, etc and having trouble losing weight, you are going to benefit from limiting the processed food period.