Ditto about testing for gluten intolerance, whether classic celiac disease or the till recently not well recognised non-celiac type of gluten sensitivity, but which is increasingly common.
Around 1% of the population have some form of celiac disease, ( various symptoms including peripheral neuropathy and skin disorders, with or without enteropathy/GI issues ), and the Maryland Institute recently put the number of people suffering from the more diffuse form of gluten intolerance at 7% of the population, so they are no longer rare at all.
And another very common cause of gastrointestinal problems is fructose malabsorption ( and the related FODMAP intolerance, to fructans in wheat, onions, etc, and to fructose in honey, apples, pears, aswell as various complex sugars ), which affects up to 40% of the population to some extent, and can be diagnosed with a hydrogen breath test.
Both of these disorders can have very very serious long-term effects on both physical and mental health, so the sooner they are diagnosed the better.
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