Fingernails grow about 3.5 mm
per month and toenails grow about 1.6 mm per month on average. The
exact rate at which your nails grow depends on several factors, such
as age, sex, diet, exercise, etc. Nails also grow faster in summer
when it is warmer. Fingernails can be seen on babies after the tenth
week of pregnancy.
Nails consist of many different parts. The visible part is known as
the nail plate and below that is the nail bed. The white, half-moon
shaped part at the base is called the lunula or distal matrix. The
tissue over the top of the matrix is called the cuticle, and the
soft tissue directly over the cuticle, is called the eponychium.
Ninety percent of nail growth comes from the matrix. Pressure within
the matrix forces dead karatinized cells out. Speed of growth is
caused be blood supply and it seems the increased activity of our
fingers vs. our toes causes more blood supply to our fingers which
leads to faster growth.
The longest fingernails ever recorded on a women belonged to Lee
Redmond of Las Vegas. After growing for 30 years, they measured a
combined length of 28 feet 4.5 inches. Unfortunately, she lost her
fingernails in a car accident in February 2009.
Clean trimmed nails are more noticeable to the beholder than the
owner.