LOS ANGELES (KABC) -- After receiving her 50th blood transfusion, 23-year-old Raeleen Whitt stopped counting. But, she says, after every bag of donated blood, she feels like a new person.
"It's like your energy is totally back and you feel like you want to go do things that you really weren't feeling up for before you got the transfusion," she explains. "It's just instant energy."
Whitt is in her third battle with leukemia. She's been in and out of hospitals since she was 16.
Her life depends on transfusions and she's grateful to all the blood donors who are helping her survive.
But blood donation recruiters at Children's Hospital Los Angeles are in crisis mode. They say the summer months are one period of time when blood donations are at their lowest.
Patients with cancer, sickle cell anemia, heart disease and traumatic injuries are in dire need so people with Type O negative blood -- the universal donors -- are asked to donate as soon as possible.
Right now, universal blood supplies are running at about 50 percent.
Raul Gonzalez, who is a blood donation recruiter at Children's Hospital Los Angeles, says summer is when everyone goes on vacation, "but what they don't know is that our patients still stay here at the hospital."
Blood donation experts at Children's Hospital L.A. say for their patients, they usually need more than a thousand units a month.
Gonzalez says to motivate you to help, think of family members and loved ones.
"This is important. We all have children, we all have family members, loved ones. To make a difference it only takes a little bit," he says. "People say that they're scared of needles, I always say think of Raeleen."
Donating blood only takes about an hour. You have to be 17 years of age or older and weigh at least 110 pounds.
Whitt can't find the words to thank all her donors, but she says she's learned to be grateful for every moment life has to offer.
"I definitely think that I appreciate things more, I appreciate my family more and my friends," says Whitt.
While people with Type O negative are most urgently needed, hospitals say they need blood donors of all types.
To find out how you can help save a life and donate blood, go here: Children's Hospital Blood Donor Center