According to one study, around 6-7% of people over the age of 70 in the United States are prescribed glucosamine to relieve symptoms.

    Many more buy it without prescription as a dietary supplement, despite there being little study evidence for its efficacy.

Yeah, point out that something hasn't been proven effective, when talking about over-the-counter customers buying it, but don't mention it when you're talking about doctors prescribing the same treatment.