The problem is that it's nearly impossible to control all the conditions so you can isolate what is causing the results. You can't really tell if your experimental results were caused by your hypothesis, or by some other piece of the hypothesis you don't know about, or by a skew in the sample. Science is hard enough to do even on the molecular scale where there are fewer variables; in people-based studies it's nearly impossible.
God, for your study, it's probably best to use the SAME set of people.* Feed them the wheat for six months, then switch them all to candy for six months. That will filter out the variations among people.
MEANWHILE, back on the original topic. It doesn't matter if wheat has nutrition. We're already getting all the nutrients from meat and veggies. The question is whether it's better to get our sugar from sugar, or from wheat which is digested into sugar. I'm only an N=1, but I cheated like a mutha with candy for the past few months and gained maybe five pounds. Actually, every couple days, I got tired of sugar and had to back off for a couple days, then started sugar again. It was more like a carb refeed than SAD. If I stopped the candy, the weight drops fast. (this is with NO exercise). But with wheat, I never got tired of it, and couldn't lose any weight at all.
If you're really in need of the micronutrients from wheat, just eat Ketchmer wheat germ from the jar and avoid the whole wheat berry. The endosperm is where most of the carbs are.
*businesses do the same thing when they track sales on a yearly basis. They track "same store" sales to filter out factors like location or customer income.