Tall, short - or got a small head? Here's what your physique reveals about your health
From your height to your foot size, body dimensions can indicate a wealth of information about your risk of conditions, from cancer through to dementia and heart disease.
Researchers at Sungkyunkwan University School of Medicine in Korea found that the taller you are, the higher your risk of developing cancer. Here, ROGER DOBSON examines what the latest research has found about your vital statistics.
IF YOU'RE TALL
Breast cancer
Women over 5ft 9in may be more likely to develop breast cancer and to die from it.
Two American studies found that tall women have an increased risk. One possible explanation is that hormones that affect women's height may also cause an increase in the amount of milk duct tissue in the breast.
Most breast tumours arise from this tissue and the more ducts, the greater the susceptibility to breast cancer.
Prostate cancer
Men over 6ft have an increased risk of prostate cancer.
In the study at Brigham and Women's Hospital, Boston, in the U.S., 22,000 men were monitored for more than 12 years. Men over 6ft tall had a 59 per cent increased risk compared to men under 5ft 7in. A study at Bristol University showed that every four inches of extra height was associated with a 6 per cent increased risk.
One theory is that growth factors are involved. Taller men tend to have higher levels of insulin-like growth factor-I or IGF-1, and higher levels have been linked to an increased risk of prostate cancer.
Pancreatic cancer
Men over 6ft 1in, and women over 5ft 6in have an 81 per cent increased risk.
Each additional inch in height was found to increase the risk of pancreatic cancer by between 6 and 10 per cent, said researchers at the U.S. National Cancer Institute. According to a report from Washington University, it might be related to the fact that the same hormones and other factors that make people grow might also increase the chance of abnormal cell growth.
IF YOU HAVE BIG FEET
Breast cancer
Women with bigger feet (the average UK shoe size is a five), trunk and shoulder breadth in childhood had a greater risk of breast cancer, according to a study at Bristol University. An increased foot size might be linked to greater calorie intake during childhood, which has been linked to an increased risk of breast cancer.
IF YOU'RE SHORT
Heart attack
Short men (under 5ft 7in) are much more likely to suffer heart attacks than men over 6ft 1in, according to a Harvard University report. The taller men were 35 per cent less likely to suffer a heart attack. Every inch of additional height also reduced the risk by 2 to 3 per cent.
Another American study found that short men had a 60 per cent greater risk of a heart attack than men 6ft 1in or taller. One theory is that shorter people might have correspondingly smaller arteries that are more vulnerable to the blocking effects from fatty deposits that can trigger heart attacks.
Stomach cancer
Shorter people are more likely to develop this disease, possibly because the cancer is linked to infection with Helicobacter pylori, the bacteria also associated with stomach ulcers. It's thought that having the bacteria in childhood might lead to a slowing in growth, say researchers at Bristol University.
High blood pressure
Shorter height and leg length are associated with higher blood pressure in men and women. A British study followed 3,000 people since birth; the greater the leg length, the lower the risk of high blood pressure.
Poor nutrition in childhood might be to blame, because smaller arteries might be more prone to high blood pressure. 'This backs up the theory that people with restricted growth in the first years of life might be more susceptible to the effects of ageing on the arteries,' say researchers at University College London.
IF YOU HAVE A SMALL HEAD
Dementia
Smaller head size and shorter legs and arms might be linked to an increased risk.
In a study of elderly women, a fifth of those with a large head size (circumference of 57-58 centimetres) had signs of dementia, compared to 70 per cent of those with the smallest heads (51-52 centimetres). Meanwhile, a German study of men and women found that head circumference below average (the average head size for a man is 58cm and a woman 55cm) was significantly associated with dementia.
One theory is that bigger heads might have a greater number of nerve cells within the brain, making them less vulnerable to degeneration - the cerebral reserve capacity hypothesis.
A link between shorter leg and arm length and higher risk of dementia has also been found by researchers at Chonnam National University Medical School, Korea. One theory is that shorter limbs might be a visible sign of poor nutrition in early life, which also impacted on the development of the brain.
IF YOU HAVE LONG LEGS
Diabetes
People with longer legs are less likely to develop Type 2 diabetes, while those with short legs have a 20 per cent increased risk of the disease. Research at Bristol University, based on 4,200 men and women, showed that each 4.3cm increase of leg length resulted in a 19 per cent reduced risk of diabetes.
Leg length is an indicator of early childhood environmental circumstances, in particular of infant nutrition. Poor nutrition has also been linked to diabetes.
IF YOU HAVE LONG FINGERS
Autism and ADHD, mental illness/depression
A range of disorders has been linked to the length of fingers, and in particular the ratio between index and ring fingers. The ratio is thought to be a marker of what was happening hormonally in the womb when the foetus developed.
It's thought a relatively long ring finger is a sign that the foetus was exposed to higher levels of the male hormone testosterone, while a relatively long index finger is a marker of the female hormone, oestrogen.
Conditions associated with a long ring finger compared to the index include autism and ADHD. Those associated with a longer index include depression.
Males, who are more likely to develop autism and ADHD, tend to have a longer ring finger relative to their index finger.
Exposure to certain hormones might increase or reduce the risk of certain conditions and traits.
'It has been suggested that autism may arise as the result of exposure to high concentrations of prenatal testosterone,' say researchers at Liverpool University.
