Study says smoking causes accelerated loss of muscle mass

13 July, 2007:

A new study says that smoking speeds up muscle loss in old age. Researchers at The University of Nottingham, the United Kingdom, say that smoking not only causes cancer, heart attacks and strokes but also leads to loss of more muscle mass over the years. This will result in an accelerated decline in physical function and, inevitably, a loss of independence.

Previous research had established that smokers tend to have a lower muscle mass than non-smokers, but until now no one has been able to explain why.

The new research, conducted by Professor Michael Rennie and Dr Philip Atherton from the University of Nottingham’s School of Graduate Entry Medicine and Health at Derby with colleagues in Denmark and the United States, has found that smoking impairs the day-to-day upkeep of muscle. This is likely to speed up a condition known as sarcopenia, a natural loss of muscle mass with age, which is linked to poor balance, gait speed, falls, and fractures.

A total of 16 men and women – both smokers with a long-standing, 20-a-day habit as well as non-smokers – in their mid-60s took part in the study, funded by the Biotechnology and Biological Sciences Research Council.

These men and woman were selected because of their similar lifestyles in terms of alcohol consumption and physical activity. They were all considered to be healthy, with no symptoms of lung disease.

During the study, doctors discovered that the amounts of myostatin, a muscle growth inhibitor, which breaks down muscle protein, were substantially higher in smokers than in non-smokers.

Dr Atherton said their tests concluded that smoking slowed the muscle protein synthesis machinery – probably impairing day-to-day upkeep of muscle.

He added: “We are all well aware of the ill-effects of smoking on the lungs, but our study reveals yet another cause of ill-health associated with smoking. Hopefully, the smoking ban in the United Kingdom will encourage people to quit smoking while they are still young, helping them to keep in good health in later life.”