Researchers at Johns Hopkins University suggest that the shelf life of human blood may be shorter than initially thought.

The researchers acknowledged that their suggestion could increase the strain on the blood banks that already struggle to provide the required amount of blood but said that the banks should consider whether storing the blood up to six weeks is of any use. The study has been published in the journal Anesthesia & Analgesia
However the findings have been questioned by some of the experts, including Sheila MacLennan, who is a consultant haematologist at NHS Blood and Transplant. “There is no definitive evidence at present that transfusing ‘older’ blood is significantly worse for patients. This is why studies like this are being done. Until we have clearer and more robust evidence of the relative safety of ‘older’ versus ‘younger' blood and the patient outcomes, we should not risk running short of blood for patients who desperately need transfusions to survive”, she said.
Source-Medindia