EYES - Start ageing at 40
Glasses are the norm for many over-40s as failing eyesight kicks in - usually long-sightedness, affecting our ability to see objects up close.
HEART - Starts ageing at 40
The heart pumps blood less effectively around the body as we get older. This is because blood vessels become less elastic, while arteries can harden or become blocked because of fatty deposits forming on the coronary arteries - caused by eating too much saturated fat. The blood supply to the heart is then reduced, resulting in painful angina. Men over 45 and women over 55 are at greater risk of a heart attack.
LIVER - Starts ageing at 70
This is the only organ in the body which seems to defy the aging process.
KIDNEYS - Starts ageing at 50
With kidneys, the number of filtering units (nephrons) that remove waste from the bloodstream starts to reduce in middle age.
PROSTATE - Starts ageing at 50
The prostate often becomes enlarged with age, leading to problems such as increased need to urinate, says Professor Roger Kirby, director of the Prostate Centre in London . This is known as benign prostatic hyperplasia and affects half of men over 50, but rarely those under 40. It occurs when the prostate absorbs large amounts of the male sex hormone testosterone, which increases the growth of cells in the prostate. A normal prostate is the size of a walnut, but the condition can increase this to the size of a tangerine.
BONES - Start ageing at 35
'Throughout our life, old bone is broken down by cells called osteoclasts and replaced by bone-building cells called osteoblasts - a process called bone turnover,' explains Robert Moots, professor of rheumatology at Aintree University Hospital in Liverpool . Children's bone growth is rapid - the skeleton takes just two years to renew itself completely. In adults, this can take ten years. Until our mid-20s, bone density is still increasing. But at 35 bone loss begins as part of the natural ageing process.
TEETH - Start ageing at 40
As we age, we produce less saliva, which washes away bacteria, so teeth and gums are more vulnerable to decay. Receding gums - when tissue is lost from gums around the teeth - is common in adults over 40.
Aging Part 2
