Water content and other aspects of brittle versus normal fingernails

Nail plate cohesion seems to be water independent

“…Brittle nails are a cosmetic issue to most patients but, when dystrophy is severe, nail function may be impaired. Stern et al 1 . studied the water content in brittle nails and concluded that there was no significant difference in water content between brittle and normal fingernail plates and that, possibly, there is no relationship between nail plate water content and nail brittleness.…”

“…Nail plates are extremely absorptive and in a constant state of influx and efflux of water 1 . The loss of water through the normal nail plate is not significantly different from that through the dorsum of the hand, although the former has no eccrine sweat glands.…”

“…Pathogenic factors leading to brittle nails impair intercellular adhesion of the corneocytes of the nail plate (onychoschizia) or cause a pathologic abnormality by involving the matrix (onychorrhexis) 1 …”

“…The lack of a relationship between nail plate water content and nail brittleness has important treatment implications 1 . Hydration of nails is thought to be the most important factor influencing the physical properties of nails, acting through changes in keratin structure 4 .…”

“…Hydration of nails is thought to be the most important factor influencing the physical properties of nails, acting through changes in keratin structure 4 . Some authors have attributed the use of hand moisturizers as a significant predicting factor for brittle nail development; 1 however, similarly to other authors, 2 our clinical experience shows that the application of emollients on the hands, especially those containing phospholipids, 9 significantly improves nail hydration, having an important role in the treatment and prevention of brittle nail syndrome, not because the nail plate is dehydrated, but because the lipid content of the nail plate and corneocyte adhesion are altered. Desiccation and exposure to chemicals should be prevented by wearing plastic gloves over light cotton gloves.…”