US Surgeon General Vivek Murthy. AP Photo / Charles Dharapak

Nearly 21 million Americans were directly affected by drug or alcohol addiction last year — roughly the same number of Americans who have diabetes — according to a new report from US Surgeon General Vivek Murthy on addiction.

But just one in every 10 of those people got treatment.

"We would never tolerate a situation where only one in 10 people with cancer or diabetes gets treatment, and yet we do that with substance-abuse disorders," Murthy told The Washington Post.

Also in 2015, according to the new report, more than 27 million people reported misusing legal prescription drugs or using illegal ones. More than 66 million people said they had engaged in binge drinking sometime in the previous month.

The answer to the problem is complex, Murthy says, and should include things like increased screenings for addiction in doctor's offices. But, he argues, it's also time to change our perception of people who've struggled with addiction.

"We also need a cultural shift in how we think about addiction. For far too long, too many in our country have viewed addiction as a moral failing. This unfortunate stigma has created an added burden of shame that has made people with substance use disorders less likely to come forward and seek help," Murthy wrote in the report.

"We must help everyone see that addiction is not a character flaw — it is a chronic illness that we must approach with the same skill and compassion with which we approach heart disease, diabetes, and cancer."

Murthy's view is one that has been echoed time and again by neuroscientists, economists, psychiatrists, and people who have struggled with addiction. Several peer-reviewed scientific studies done over the past decade support the idea as well.

In her recent book "Unbroken Brain," neuroscience journalist and author Maia Szalavitz calls addiction a learning disorder, much like ADHD, and says it needs to be treated as such. This treatment regimen would vary based on the individual but could include things like cognitive behavioral therapy, a form of psychotherapy in which the therapist and patient work together to swap unhealthy learned patterns with more constructive ways of thinking, and potentially medication.

Addiction "is a form of pathologic learning," Szalavitz told Business Insider earlier this year. "Overwhelming changes occur in the brain region involving areas that evolved for things like love and sex and feeding."

That means addiction will create what she calls "very powerful drives" — strong desires to take the drug repeatedly even if it's not providing any pleasant effects. It's something that runs contrary to what many people think of when they think of an addict, someone who uses simply because it feels good.

"We've just been getting this completely backwards by failing to address the role of learning," Szalavitz said. "If you want to call it a disease, the kind of disease it is is a learning disease."