ST. CLOUD -- The American Red Cross is in need of more blood donors this time of year -- which is why January is National Blood Donor Month.

Seasonal factors like cold weather and illnesses cause for a shortage of blood donations.

"We just want to remind the public that it's a great time to roll up the sleeve and donate blood because the need is constant," says Sue Thesenga with the Red Cross.

Thesenga says 33% of Americans are eligible to give blood, but only 8% actually donate.

"Every two seconds, someone in the United States needs a blood transfusion, and a lot of people don't realize that until they or someone they love needs a blood transfusion."

The Red Cross says they provide 40% of the nation's blood supply and the relatively short shelf life of red blood cells (42 days) and platelets (five days) contribute to the constant need of blood donations.

- Must weigh at least 110 pounds.
- Must be 17 years old with valid ID (16 year-olds eligible with parental consent).
- Cannot donate when ill.
- No age limit, as long as you're in good health.
- Can donate every 56 days, or about six times per year.