Steve is showing signs of reactive hypoglycaemia. More complex carbohydrates might help.

Robomatic is right: the problem with specialist diets is their practicality for you. Try excluding nightshades. No question that it can make an enormous difference for some cases of arthritis, and you can verify if they're the problem very easily. But consistent total elimination for years on end takes a gigantic effort: all the logistics of getting food into your mouth needs to change, your social eating patterns have to be totally different, and it's impossibly difficult to explain to people who have no idea what tomatoes, cigarettes, mashed potato and tabasco might have in common.

My wife used to work with this stuff professionally as one of the UK's very few registered dietitians doing food intolerance. Finding the right diet wasn't the issue, the problem was making it feasible for people to follow it. At the extreme - she even had to tell some parents to give up and resign themselves to their child declining into an early death with seizures and mental retardation, because they didn't have a prayer of keeping him on the PKU diet that could have given him a normal life.