Re: nail issues above:
I don't have time to search this out to prove it but from my reading I believe this is a sign of low copper. If your hormones have started to wind down (over 40 or 50 for women, over 60 or 70 for men) you may be copper deficient because estrogen and testosterone increase the half life of copper. Taking zinc with insufficient copper is not a good idea. methionine synthase enzyme uses copper, so once the methyl cycle is working, it will use some copper, and if you don't have enough, perhaps making you deficient elsewhere. The problem is that there is no accepted reliable way to measure copper status other than liver biopsy (invasive). You can do a google search on the string "Lowe copper Cambridge" to find a paper which reports on studies into copper's role in bone mass, in particular citing details from a study in which bone mass was increased by calcium:zinc:copper:manganese in the ratio: 1000:15:5:2.5. The only unusual thing in that is the copper dose. If you look at any standard multiple you will find copper at 1.5 to 2 mg per 15mg for zinc. It is well known that multi vitamin use is linked to osteoporosis. *I* believe it is because they cause copper deficiency. You can get a hair analysis at traceelements.com to determie copper status to the best of our current ability. copper is a poison and I am afraid of it so I am sure I do not supplement enough. What I do is use a copper solution called CP serum from skin biology (online) to get "a little extra copper". It took care of some abnormal skin on my neck that developed at menopause. trace elements diagnosed me borderline low copper after menopause and not at all deficient before. So I think they are doing a crediable job of determining approximate copper status.
Copper is what allows cross-linking of collagen. Without enough your skin is made with cells sitting one atop another like the bricks of a house that are not staggered and therefore not strong. Since your blood vessels are skin, and skin w/o cross-linking is not strong, the blood vessels won't withstand much pressure and can burst (aneurism). I believe nail collagen works the same way, but not positive. You can search on google/scholar to see what you think.
Rydra