Medical AstrologyAstrological diagnoses and other health issues are discussed here. Given that there are so many outer and inner influences on one's health (alimentation, sports, medication, past medical antecedents, state of mind, etc.), an astrological diagnosis is only one of many things to consider when determining your healthiness.
I don;t know any cancerians who suffer from asthma, but I have seen a lot of cases of asthma in those born sun in Gemini or with Gemini on H6 cusp. I was an asthmatic myself- I am sun Libra but gemini is in my H6 cusp and my mercury in H10 is afflicted by Uranus cj jupiter in cancer (late in degree and on H8 cusp). One would think air signs might be more disposed to disorders of the respiratory tract in the same way that fire signs are more disposed to feverish illnesses and blood disorders...I have noticed cancerians are more prone to disorders of the gut and moon ruled things like glands and fluids in the body.I have been keeping data on health issues and astrological relationships for many years....my taurus daughter suffers throat illnesses when she gets the flu whereas a flu will go straight to my chest and my virgo ex husband always gets a gastric version of the flu...I don't think your ideas are wrong at all....lillyjgc