Blood donation reduces the risk of heart disease, say scientists led by Margit Egg from the University of Innsbruck, Austria. Donating blood is especially beneficial to shift workers, who are known to suffer from various heart diseases due to jetlag.

Australian scientists have found that donating blood could very well reduce the risks of heart disease. A team of researchers led by Margit Egg from the University of Innsbruck, Austria experimented with zebrafish, which are model organism and like humans are active during the day. Jet lags as seen in humans have extremely negative effects on red blood cells, which explain why shift workers suffer most from heart-related illnesses. This can be reversed by bringing in fresh and young red blood cells through blood donation.

The fishes were subjected to shift patterns - alternate short (7 hour) and long (21 hour) days, similar to the ones shift workers face in the industry. The findings surprised researchers since the fishes, which were "jetlagged," showed high number of aged red blood cells that were collected in their blood vessels. "Normally there is a balance between newly produced red blood cells and old ones which are removed from the blood," Egg said.

Since the old cells are less flexible, they get stuck in the spleen and liver where they are surrounded by white blood cells. However, researchers are still trying to figure out why jetlag prevents this removal process.

Large number of red blood cells in the vessels increases the chance of a clot that can eventually lead to a heart attack. Shift workers, who are at a 30 per cent higher risk of cardiovascular diseases, will be at an advantage if they donate blood. Apart from that, it was also found that the aged cells also reduce the oxygen-carrying capacity of the blood.