To pro-alternative folks like myself it just means "not in the medical textbooks yet". Most 'alternative' approaches do have rigorous studies backing them up, just recent and ignored by a lot of people.
Believe it or not, western medicine doesn't have all the answers, especially when it comes to chronic conditions. Thinking that steroids and antibiotics will cure IBS is quack science, and that's what's being practiced in western medicine.
"Western" medicine dramatically improved in the last few decades. "Alternative" medicines do not have the intellectual framework or the ability to improve.