Laughing at conspiracy theories is good fun – at least until they turn out to be true.

Take the conspiracy surrounding the “Project Sunshine,” for example.

In the wake of Hiroshima and Nagasaki, the U.S. government commenced a major study to measure the effects of nuclear fallout on the human body.

1. The horror of 'Project Sunshine'

Conspiracy: The government was stealing dead bodies to do radioactive testing.

The truth: The government was stealing parts of dead bodies. Because they needed young tissue, they recruited a worldwide network of agents to find recently deceased babies and children, and then take samples and even limbs – each collected without notification or permission of the more than 1,500 grieving families.

2. Bad booze

Conspiracy: During Prohibition, the government poisoned alcohol to keep people from drinking.

The truth: Manufacturers of industrial alcohol had been mixing their product with dangerous chemicals for years prior to Prohibition.

But between 1926 and 1933, the federal government pushed manufacturers to use stronger poisons to discourage bootleggers from turning the alcohol into moonshine.

That didn't stop the bootleggers or their customers, and by the end of Prohibition, more than 10,000 Americans had been killed by tainted booze.

3. The first lady who ran the country

Conspiracy: A stroke rendered President Woodrow Wilson incapable of governing, and his wife surreptitiously stepped in.

The truth: Wilson did suffer a debilitating stroke towards the end of his presidency – but the government felt it was in the country's best interest to keep things quiet.

The public didn't learn about the stroke for months, during which time his wife, Edith Wilson, was making most executive decisions.

Despite Mrs. Wilson claiming that she acted only as a “steward,” historians who have analysed the Wilson term in office confirm that for well over a year, Mrs. Wilson was effectively president.

4. Government mind control

Conspiracy: The CIA was testing LSD and other hallucinogenic drugs on Americans in a top-secret experiment on behaviour modification.

The truth: The program was known as MK-ULTRA, and it was real.

The CIA started by using volunteers – the novelist Ken Kesey was one notable subject.

But the program heads soon began dosing people without their knowledge; MK-ULTRA left many victims permanently mentally disabled.

5. The Dalai Lama's impressive salary

Conspiracy: The Dalai Lama is a CIA agent.

The truth: Perhaps the reason the Dalai Lama is smiling in all those photos has something to do with the six-figure salary he pulled down from the U.S. government during the 1960s.

According to declassified intelligence documents, he earned $180,000 in connection with the CIA's funding of the Tibetan Resistance to the tune of $1.7 million per year.

The idea was to disrupt and hamper China's infrastructure.

6. John Lennon was under government surveillance

Conspiracy: The FBI was spying on former Beatle John Lennon.

The truth: They most certainly were. Like many counter-culture heroes, Lennon was considered a threat: “Anti-war songs, like “Give Peace a Chance” didn't exactly endear former Beatle John Lennon to the Nixon administration,” NPR reported in 2010.

“In 1971, the FBI put Lennon under surveillance, and the Immigration and Naturalization Service tried to deport him a year later.”

7. The government is spying on you

Conspiracy: With the advances in technology, the government is using its vast resources to track citizens.

The truth: In 2016, government agencies sent 49,868 requests for user data to Facebook, 27,850 to Google, and 9,076 to Apple, according to the Electronic Frontier Foundation (the EFF), a major non-profit organisation that defends civil liberties in the digital world and advises the public on matters of internet privacy.

8. Fake battle, real war

Conspiracy: The Gulf of Tonkin incident on August 2, 1964, was faked to provoke American support for the Vietnam War.

The truth: By the time news reached American ears, the facts surrounding the North Vietnamese attack on the American Naval ship Maddox were already fuzzy.

Declassified intelligence documents have since revealed that the Maddox had provided support for South Vietnamese attacks on a nearby island and that the North Vietnamese were responding in kind, according to the U.S. Naval Institute.

The event “opened the floodgates for direct American military involvement in Vietnam.”

9. Big Tobacco knew that cigarettes caused cancer

Conspiracy: For decades, tobacco companies buried evidence that smoking is deadly.

The truth: At the beginning of the 1950s, research was showing an indisputable statistical link between smoking and lung cancer, but it wasn't until the late 1990s that Philip Morris even admitted that smoking could cause cancer.

10. There is alien evidence in the American Southwest

Conspiracy: E.T. is buried in the desert of New Mexico.

The truth: This one is real: The Atari video game E.T., the Extra-Terrestrial failed so miserably that the company buried unsold cartridges in a desert landfill. (Wait, what did you think we meant? Real aliens? In New Mexico? Not yet, anyway.)

11. Canada tried to develop 'gaydar'

Conspiracy: The Canada government was so paranoid about homosexuality that it developed a “gaydar” machine.

The truth: It really happened: In the 1960s, the government hired a university professor to develop a way to detect homosexuality in federal employees.

He came up with a machine that measured pupil dilation in response to same-sex-erotic imagery; the Canadian government used it to exclude or fire more than 400 men from civil service, the military, and the Mounties.

12. The Illuminati and the U.S. government

Conspiracy: A secret society that rules the world – the Illuminati – and the U.S. National Security Agency (NSA) are in cahoots.

The truth: We're here to tell you that a link does, in fact, exist.

Of course, that “link” is actually a hyperlink (i.e., an electronic link between two Internet sites).

If you type Illuminati backwards – Itanimulli – into a web browser, you will land on the NSA website.

Click this link if you dare:

Written by Lauren Cahn. This article first appeared in Reader’s Digest. For more of what you love from the world’s best-loved magazine, here’s our best subscription offer.