MARSHFIELD, Wis. -

A Marshfield man who has donated blood platelets once a month since 1997 is approaching the 19-gallon donation mark.

Don Nystrom, 72, has been donating since he retired 16 years ago. He said he does it because he wants to help people.

During platelet donation, a portion of blood is collected and transferred to a centrifuge, which separates platelets and plasma. The remainder is transferred back to the donor.

Platelets are blood cells that clot to prevent bleeding. They're vital in treating cancer patients, people recovering from surgery and trauma victims.

Nystrom told the Marshfield News-Herald he's lucky he has good health. He said if the tables are turned he hopes another donor would do the same for him.