The story of Gilgamesh, the protagonist throughout ancient Mesopotamian mythology, is one of the earliest tales that addresses humanity’s attempts to defy death.

Gilgamesh, whose feats are recounted in five epic poems, is told by the king Utnapishtim to stay awake for six days and seven nights to prove that he is worthy of being immortal. Unfortunately for Gilgamesh he falls asleep almost immediately.

Utnapishtim still tells Gilgamesh there’s a plant at the bottom of the ocean that restores youth. Gilgamesh even gets his hands on it. But as he’s swimming, a snake steals the plant and disappears into the water. Gilgamesh then returns to his home of Uruk without the secret for immortality.

“The lesson of Gilgamesh is that we’ll never conquer mortality and we need to come to terms with that and think about living a good life,” says Stephen Cave, the author of Immortality: The Quest to Live Forever and How It Drives Civilization.

Ancient Egyptian rulers were “completely obsessed with immortality,” Cave says.

They were convinced that there was an afterlife and that bodies needed to be preserved so they could act as homes for the spirits.

That’s why the Egyptians  spent a huge amount of time, effort, and money on mummification, as well as the associated rituals that went into burying leaders, such as building pyramids.

 “Some scholars even estimate that 40 percent of Egyptian GDP went into the afterlife industry, mummification, and building temples” Cave says.

But Egyptians also did all they could to extend their lives with medicine and potions, Cave says.

“Mummification was very much plan B,” says Cave. Before they were mummified, people were given various medicines and potions to try and keep them alive. “In very early texts, medical papers, and papyrus, you see instructions on how to fix a broken leg,” says Cave. “Then it will also say, ‘Oh yeah, if you do this, you’ll live forever.’ It’s an ancient obsession.”

As the first emperor of China, who unified the country in 221 B.C., Qin Shi Huang is a very important historical figure. But Qin Shiu Huang had a major hobby.

“His real obsession was living forever,” notes Cave.

Chinese history is replete with legends of magical elixirs that could make people immortal and “he went around his huge empire looking for alchemists, wizards, and physicians who could give him an elixir for life,” says Cave.

Qin Shi Huang was so fixated with prolonging his life that “he banned the mention of the word death in his presence. He had poets following him around singing songs about immortality,” Cave adds.

But Huang got sick in middle age and died at 49. One popular theory is that his pursuit of immortality was the very reason for his premature demise and he actually died after consuming too much mercury. This hypothesis is backed by the fact that, when modern archaeologists found Huang’s tomb, its mercury concentration was 100 times higher than normal.

Melting down gold and drinking it was an anti-aging fad in 16th century France spearheaded by courtier Diane de Poitiers, and the practice also existed in ancient China and Egypt.

“Alchemy exists in the west and east, with its primary goal being immortality,” explains Cave. “Gold was seen as incorruptible and the purest of all metals.”

Chinese alchemist Wei Boyang in 2,500 B.C. promoted the theory that consuming “small quantities of substances that were immortal” would lead to them living longer, says Olshansky.

It also helped that a lot of rulers had bought plenty of gold to prove their wealth, so there was more than enough laying around for alchemists to melt down and serve up.

As the mistress of King Henry II of France, De Poitiers also had access to plenty of gold, right up until she died at the age of 66. She apparently consumed plenty of it, too. When her body was found in 2008, the level of gold found in her hair was 500 times more than normal, while traces of mercury were also found in her bones.

There was one certain impact when drinking gold, though, says Cave: “You just have an expensive poo.”

In 1492, after Pope Innocent VIII suffered a stroke a decision was made to transfer blood from three healthy young men into his veins. This is believed to have been the first blood transfusion in recorded history. But not only did Pope Innocent VIII die from the procedure, so did the men.

The first major step in blood transfusion occurred in 1628, when English physician William Harvey discovered the circulation of blood. In 1665, physician Richard Lower was able to keep a dog alive by transfusing blood from other dogs. Two years later, there were two separate reports of blood transfusion from sheep to humans.

Blood transfusion technology particularly advanced during the 20th century. Geoffrey Keynes developed a portable blood transfusion kit in the World War I, which enabled doctors to treat soldiers on the battlefield. In World War II Dr. Charles Drew spearheaded the creation of huge blood storage systems and donation units, which were known as Bloodmobiles.

Progress is still being made in the field.  “It was recently demonstrated that transfusions of young blood do, in fact, have rejuvenation effects,” says Cave. He then quickly adds the important caveat of, “These tests were demonstrated in mice.”

Some scientists have started experimenting with transfusing blood plasma in humans. But it’s still way too early to know whether this will actually lead to people living for significantly longer, or if it’s just the latest dead-end in the seemingly never-ending pursuit of immortality.