The reality of America's heroin epidemic hit Dr. Jeremy Engel one summer's day in August 2012. Engel, a family practitioner in northern Kentucky, recalled how five of his 18 patients told him they had a child or grandchild using heroin, or who had overdosed. Another woman came into his practice after hours and said her daughter needed heroin addiction treatment. Then his colleague in the emergency department casually mentioned that they had also admitted a patient for kidney dialysis who was overdosing on heroin.

Similar scenes have unfolded at doctor's offices across America. According to data compiled by the Center for Disease Control and Prevention (CDC) from 60 million death certificates, the rate of fatal heroin overdoses almost tripled between 2010 and 2013. The deaths were not concentrated in any region, and the users were both rich and poor. But the vast majority had one thing in common: They were white.

A recent analysis of the CDC data by the New York Times found that the rising death rates of white adults between the ages of 25 and 34 made them "the first generation since the Vietnam War years of the mid 1960's to experience higher death rates in early adulthood than the generation that preceded it." But while the mortality rate for whites has been steadily rising, the death rates of blacks and Hispanics has continued to fall.

Nobody can seem to agree why this is happening.

"It has hit every white socioeconomic class," said Dr. Andrew Kolodny, chief medical officer at Phoenix House, a nonprofit institution that treats substance abuse in 10 states. "The key driver is exposure to opioids."

Kolodny thinks the correlation between opioid prescriptions and addiction explains why the problem is so overwhelmingly white. Between 1997 and 2011, the number of individuals seeking treatment for addiction to opioids increased by 900 percent. Opioid painkillers like OxyContin, which came onto the market in 1996, were the cause of three-quarters of drug overdose deaths in that period.

In 2013, the FDA imposed tighter regulations on the pills, which in turn drove up their street value. Americans who were already hooked turned to heroin, which is largely supplied by Mexican cartels. Black tar heroin, produced from poppies that grow in Mexico's rugged Sierra Madre mountains, offers a cheap and potent alternative to prescription painkillers.

So at what point did this become a white issue? Kolodny suggests that underlying racism by doctors might be the answer. He cites a study that mined Medicare data between 2007 and 2012 to identify trends in opioid prescriptions. The study concluded that white patients were being prescribed opioids at a higher rate than their minority counterparts.

'It has hit every white socioeconomic class.'

"The stereotype that minorities are more likely to become addicted to drugs or divert [their medication] is rooted in the recent memory of two devastating drug epidemics — heroin in the 1970s and crack cocaine in the late 1980s, which disproportionately affected low-income minority populations," Kolodny said.

The study cited by Kolodny isn't the only time the medical community has been accused of discrimination. In 2007,researchers at the Disparities Solutions Center, a Harvard University and Massachusetts General Hospital affiliate, found evidence of bias among physicians, and concluded that race could be a determining factor in the kind of care a patient receives.

Sam Quinones, author of Dreamland: The True Tale of America's Opioid Epidemic, a book that chronicles the rise of OxyContin and explains how Mexican heroin dealers met the surging demand for opiates, isn't buying the claim that racist doctors are singlehandedly responsible for the vast disparity between whites and people of color in the frequency of fatal opioid overdoses.

"There's an awful lot of doctors out there," Quinones. said. "I can't imagine that every single one has that feeling."

According to Shannon Monnat, an assistant professor of sociology at Penn State University, there's data to back up Quinones' hunch. Monnat has done extensive research on the demographics of opioid abuse. She suggested that the overdose disparity has more to do with health insurance coverage and health care access, which makes whites more likely than blacks to visit a doctor — and thus more likely to end up with a prescription for painkillers.

"Patients who regularly see the same doctor have more opportunities to build a personal and trusting relationship with their doctors," she said, noting that doctors might be more comfortable prescribing opioids to familiar patients.

Data from the CDC shows that 13 percent of white people under the age of 65 didn't have health insurance in 2012, compared to 18 percent of African-Americans and 30 percent of Hispanics.Black and Hispanics were also more likely to either delay or not seek medical treatment because of the cost.

'It's a lot of money that people have to pay for the doctor's visits. It doesn't matter what race they are.'

Quinones noted, however, that the proliferation of so-called "pill mills" — operations where unscrupulous doctors rubber-stamp prescriptions for opiates — have been a contributing factor in the spread of addiction. He also suggested that "affluenza" — a term used to describe malaise among wealthy individuals — may have led more whites to abuse pills and try heroin.

"There are a lot of cases where [a doctor's] scruples and ethics don't enter the equation at all," he said. "It's a lot of money that people have to pay for the doctor's visits. It doesn't matter what race they are."

There's another possible explanation: The drug epidemics that devastated minority communities in the '70s, '80s, and '90s created a shared aversion to hardcore drugs like heroin and crack. Marcus Anthony Hunter, an assistant professor of Sociology and African American Studies at UCLA, said minority communities are still feeling the effects of the zero-tolerance response by law enforcement to those drug epidemics.

Even though addiction still afflicts minority communities in urban areas, Hunter said, heavy-handed policing tactics have made it much harder to acquire drugs. According to his theory, heroin dealers in whiter suburbs have an entrepreneurial advantage over their urban counterparts in that they are much less likely to be shut down by the cops.

"Now that the problems of drugs have noticeably reached the vanilla suburbs, questions and claims or morality have been contested in ways often unavailable to urban minority communities," Hunter said. "Where urban minority areas are thought to be amoral breeding grounds, suburban white areas are thought to be upstanding, respectable force fields from the ills of drug use. As it turns out, neither is exactly true."

Regardless of why whites have been more affected, the upshot is that the current epidemic is being handled very differently than past drug scourges. Many states are now funding harm reduction approaches, while also favoring new medical technology and rehabilitation over criminalization and incarceration. So far, the new model appears to be working.

Programs that utilize the overdose antidote naloxone, which is sold under the brand name Narcan, are credited with reversing more than 26,000 overdoses since 1996. A report by the Harm Reduction Coalition found that as of June 2014, at least 644 "community-based opioid overdose prevention programs" had been launched across the US, providing naloxone to "laypeople" such as drug addicts and their families.

Watch the VICE News documentary: Back From the Brink: Heroin's Antidote

The effect of increased naloxone availability has been dramatic in some areas. Brockton, a predominantly white city of about 94,000 south of Boston, averages about three overdoses a day. But from January 13-17, not one of the city's 45 heroin overdoses was fatal, owing to the use of naloxone to resuscitate the users.

Other parts of the country are less progressive. Engel, the family practitioner in Kentucky, says he's tired of seeing families torn apart by overdose deaths and addiction. The doctor said that heroin addiction can be dealt with appropriately using a combination of drugs, but addiction clinics, especially in the country's heartland, are far and few between. Some physicians are reluctant to work with patients.

"There is a huge stigma," he said. "Doctors don't want to take the risk."

He said that northern Kentucky has been particularly blighted by opioid and heroin addiction, and that the community in his area — which is mostly white — needs to overhaul its entire approach in order to stamp out the epidemic.

"There's a frontier culture in Kentucky," He said. "It's a very stubborn culture… where people would rather do it wrong and do it their own way than do it right. People need to take thoughtful actions to fix this problem."