Or not? Took it for 4 months, never more than 4iu and ramped up like mentioned, the last 2 months only being 2iu, and it never went away. Massive pain and numbness in hands, arms falling asleep at night. Real bummer was after i stopped taking it it took another 3 months for the sides to go away, they diminished daily but so slowly it took months. Hard to have any kind of well being with that amount of daily pain
My worry is, like a lot of counterfeit supplements, they learn what people expect for side effects and find cheap chemicals that will give those sides. Probably not hard to find something that will swell your joints up and maybe use a little too much of it.