I am shedding right now and all my hairs have the white bulb at then end. I've heard a lot of posters say its sebum or product or the follicle. Nobody seems to know for sure what it is or whether its a good or bad thing.
When I loose a hair there is usually a white substance at the end that can be cleaned off. The white bulb remains underneath this and cannot be wiped off or detached from the hair strand, its is a part of the hair, they are one unit.
My fear is that it means this hair is lost forever. The photo posted shows two hairs coming from this one bulb. I have experienced this also. Just yesterday I lost a long hair with another smaller and thinner one attached to the same white bulb, the smaller hair looked like it had just started to grown and maybe would have eventually replaced the other hair.
If they both have fallen out with the same white bulb attached, which is the starting point for growth from what I can see, my fear that there is no way for this hair to grow again (no starting point if you will) and that these hairs are indeed lost forever.
We need more definitive answers on this