Newt Gingrich, a Fox News contributor and reported leading contender to be Donald Trump’s running mate, has spammed his email list subscribers with sponsored emails claiming that “cancer was cured back in 1925” and the “actual cure” can be found through a subscription newsletter.

The people behind the Gingrich-sent emails have been criticized as pulling off “an unbelievable, immoral con job,” skirting “the line between spammy and scammy,” and using people’s “faith as a way to sell them bullshit ‘miracle’ cancer cures and nutritional supplements.”

Similar cancer “cure” emails were an issue during the Republican presidential primary when then-candidate Mike Huckabee was criticized for sending out sponsored emails from the same company, Health Revelations.

Gingrich served as House speaker during the 1990s and was “the first speaker of the House to be punished by the House for ethics violations,” according to CNN.com. His media work has crossed multiple ethical boundaries, including by posing conflicts of interest.

Numerous reports have identified Gingrich as being on Trump’s shortlist of potential running mates. Gingrich is set to campaign with Trump at a July 6 rally in Ohio.

The Republican has attempted to cash in on his post-politics life by becoming a consultant and media personality. He has also made money by renting out his Gingrich Productions email list to shady entities. Gingrich list subscribers over the years have received supposed insider information about “Obama's 'Secret Mistress,'” a “weird” Social Security “trick,” the Illuminati, and Fort Knox being “empty.”

Among the shadiest sponsored emails from Gingrich are a series of missives touting claims that “cancer was cured back in 1925” and “the actual cure” for cancer can be found by ultimately subscribing to a newsletter for $74. The emails are from Health Revelations and Health Sciences Institute (HSI), which are both owned by NewMarket Health, LLC, a subsidiary of Agora, Inc.

Gingrich Productions sent a February Health Revelations email claiming to have “the TRUTH” about preventing cancer and deadly tumors.

The email linked to a pitch page claiming that “all cancers were cured back in 1925” but the government has been covering up the evidence. The email ultimately asks readers to subscribe to the Health Revelations newsletter, which costs $74 a year.

The following are screenshots of the pitch page and signup page:

In 2013, Gingrich’s list sent a similar email from Health Revelations which also claimed that “cancer was cured back in 1925” and a “God-fearing American doctor … gives the actual cure.”

In October and December 2015, Gingrich Productions sent an email from Health Sciences Institute claiming that “researchers investigating” the Bible have “unlocked a connection to a stunning cancer-fighting power... a breakthrough so monumental, it's poised to make traditional cancer therapies obsolete... and save millions of lives.” HSI is a subscription newsletter, which costs $74 a year.

HSI and Health Revelations have been heavily criticized by those who have examined their practices.

Mother Jones reporter Tim Murphy profiled Health Sciences Institute and Agora and found that “Agora's emails skirt the line between spammy and scammy,” pointing to an email that HSI sent in 2014 which “claimed that the Obama administration was blocking a miracle cure that ‘vaporizes cancer in six weeks.’”

WAFF, NBC’s Huntsville, AL, affiliate, debunked Health Revelations' claims “that the cure for cancer -all cancers- is hidden specifically on page 859 on an ancient version of the King James Bible.” Ordained minister and cancer researcher Rob Seitz slammed Health Revelations, telling the station: “Our creator did not encode that. I think it is an unbelievable, immoral con job. … The most unethical thing we can do is to intentionally give cancer patients false hope in an attempt to get money from them.”

WAFF also reported that it contacted the University of South Florida, which “supposedly conducted the studies on the Matthew 4 Protocol as touted by Brian Chambers with Health Revelations that proved the Bible's secret cure. The University of South Florida confirmed it ‘has done no such verification.’ They go on to say, ‘There is no way this is true and it is very disturbing that our name would be attached to this.’”

The American Prospect’s Paul Waldman, who has written for The Washington Post, The Week and Media Matters, commented in 2015 that Health Revelations is “another con artist, whose con is to use people's religious faith as a way to sell them bullshit ‘miracle’ cancer cures and nutritional supplements.”