How many times can you safely give blood in a year?

I believe you can safely donate once per eight weeks. 16 weeks if you do double red blood cells.

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To give blood for transfusion to another person, you must be healthy, be at least 17 years old or 16 years old if allowed by state law, weigh at least 110 pounds, and not have donated blood in the last 8 weeks (56 days) or a donation of double red cells in the last 16 weeks (112 days). “Healthy” means that you feel well and can perform normal activities. If you have a chronic condition such as diabetes or high blood pressure, “healthy” also means that you are being treated and the condition is under control.

Other aspects of each potential donor’s health history are discussed as part of the donation process before any blood is collected. Each donor receives a brief examination during which temperature, pulse, blood pressure and blood count (hemoglobin or hematocrit) are measured.

Making donations for your own use during surgery (autologous blood donation) is considered a medical procedure and the rules for eligibility are less strict than for regular volunteer donations.

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