The Red Cross has seen a 40% decrease in blood donations over the last 20 years. Experts say Gen Z is to blame.

• The American Red Cross has seen 40% fewer blood donations over the last 20 years.
• The Red Cross said the it would need 8,000 weekly donations in January to meet demands.

Fewer people are donating blood, and experts say younger generations are at the heart of the problem.

Dr. Eric Gehrie, the executive medical director of the American Red Cross, told NBC News that the organization has seen a 40% drop in people donating blood over the last 20 years.

Over the 2023 holiday season, Gehrie said the Red Cross was 7,000 units short of meeting demand from hospitals.

The most recent National Blood Collection and Utilization Survey, administered by the Department of Health and Human Services, found that blood donations by teens and young adults have steadily declined over the last decade. From 2019 to 2021, the survey says blood donations from people 16 to 18 dropped by a whopping 60%.

"If that trend continues, we're going to be in a very difficult situation," Dr. Claudia Cohn, chief medical officer for the Association for the Advancement of Blood & Biotherapies, told NBC.

In April 2023, the Red Cross launched a t-shirt campaign with Snoopy standing in front of the large Red Cross logo, hoping that the campaign would attract more young people to give blood, The New York Times reported at the time. The campaign quickly went viral on TikTok. One video about the campaign gained more than four million views in just a few days.

Gehrie told NBC the campaign was overwhelmingly successful with more than 70,000 people under 35 donating in the months after its launch. Still, he estimated that the organization will need an additional 8,000 donations every week this month to meet hospital demands.

Gehrie speculated that minimum height and weight requirements on who can donate blood imposed by the FDA in 2015 might be part of the reason fewer young people are donating blood, according to NBC. Anyone who donates blood must weigh at least 110 pounds, and there are additional height and weight requirements for those under 18.

"We had a lot of high school donors that were deferred," Gehrie told the outlet. "We don't want those young donors to get the impression that because they were deferred for that reason, that they can never donate again."