The term endorphin, short for endogenous morphine, is often invoked to explain the high. Endorphin attaches to the same receptors in the brain that heroin (which metabolizes to morphine), oxycodone and codeine bind to. Activating these receptors in turn leads to the release of dopamine, one of the neurotransmitters principally responsible for pleasure in the brain.

Endorphins are connected to runner’s high through circumstantial evidence and evidence from animal studies. One particularly interesting study forced mice to swim every two hours. When the mice were let off their exercise routine, they exhibited symptoms similar to morphine withdrawal. The mice, apparently, had become physically addicted to opiates produced in their own body during exercise, and when they stopped the exercise regimen, they acted as if they’d been cut off from a serious morphine dependency.

In humans, indirect measures such as endorphin levels in the blood serum pointed towards endorphins being behind runner’s high. On the other hand, this need not indicate that there are heightened levels of endorphins in the central nervous system, which is where they need to be to impact mood and pain sensations. More important, perhaps, is the fact that runner’s high can be negated with naloxone, an anti-opioid agent often administered to people who overdose on opiates. This is what you’d expect if the effects were really due to endogenous opioids.

In 2008, German researchers tried measuring endorphins directly in humans after exercise. In their pilot study, they recruited ten experienced distance runners. The subjects were screened for drug abuse, and only runners who stated that they had experienced runner’s high were included. The volunteers were then subjected to PET scans before and after a two-hour long distance run. They were also asked to rate their mood before and after. The researchers found that, as expected, the runners reported being significantly happier right after a long run than right before or on rest days. Accompanying their subjective reports, the objective brain scans found significant activation of opioid receptors thirty minutes after a long run. This was the first direct, in vivo evidence of an endorphin-generated high.

If endogenous opioids are really responsible for the feelings of well-being working out gives us, that could explain the well-documented inverse relationship between depression and regular exercise. Some studies have found that regular exercise is as effective, or even more effective than antidepressants or cognitive-behavioral therapy for treating depression. In addition, you’re significantly less likely to become depressed in the first place if you work out. Finally, it could explain stories of injured athletes who continue to train despite doctors’ advice to the contrary and injure themselves further. Perhaps, like mice, humans really can get physically addicted to the good feeling of a hard workout.

Dock Phillip Ellis, Jr. was a professional baseball player who pitched for the Pittsburgh Pirates, among other teams in Major League Baseball. His best season was 1971, when he won   19 games for the World Series champion Pirates and was the starting pitcher   for the National League in the All-Star Game. However, he is perhaps best remembered for throwing a no-hitter in 1970 while under the influence of LSD.

As Ellis recounted it:

“I was in Los Angeles, and the team was playing in San Diego , but I didn’t know it. I had taken LSD….. I thought it was an off-day, that’s how come I had it in me. I took the LSD at noon. At 1pm, his girlfriend and trip partner looked at the paper and said, “Dock, you’re pitching today!”

“That’s when it was $9.50 to fly to San Diego. She got me to the airport at 3:30. I got there at 4:30, and the game started at 6:05pm. It was a twi-night doubleheader. I can only remember bits and pieces of the game. I was psyched. I had a feeling of euphoria.”

“I can only remember bits and pieces of the game. I was psyched. I had a feeling of euphoria. I was zeroed in on the (catcher’s) glove, but I didn’t hit the glove too much. I remember hitting a couple of batters, and the bases were loaded two or three times. The ball was small sometimes, the ball was large sometimes, sometimes I saw the catcher, sometimes I didn’t. Sometimes, I tried to stare the hitter down and throw while I was looking at him. I chewed my gum until it turned to powder. I started having a crazy idea in the fourth inning that Richard Nixon was the home plate umpire, and once I thought I was pitching a baseball to Jimi Hendrix, who to me was holding a guitar and swinging it over the plate. They say I had about three to four fielding chances. I remember diving out of the way of a ball I thought was a line drive. I jumped, but the ball wasn’t hit hard and never reached me.”

 ”I was zeroed in on the catcher’s glove, but I didn’t hit the glove too much. I remember hitting a couple of batters and the bases were loaded two or three times. The ball was small sometimes, the ball was large sometimes, sometimes I saw the catcher, sometimes I didn’t. Sometimes I tried to stare the hitter down and throw while I was looking at him. I chewed my gum until it turned to powder. They say I had about three to four fielding chances. I remember diving out of the way of a ball I thought was a line drive. I jumped, but the ball wasn’t hit hard and never reached me.”

The Pirates won the game, 2-0, although Ellis walked eight batters. It was the highpoint in the baseball career of one of the finer pitchers of his time, and arguably,one of the greatest achievements in the history of sports.

From 1984 New York Times Article ‘Sports People: Drugs and No-Hitter’

In 2007, researchers at the University of Bordeaux, France, reported  that “intense sweetness can surpass cocaine reward… . The supranormal stimulation of these receptors by sugar-rich diets, such as those now widely available in modern societies, would generate a supranormal reward signal in the brain, with the potential to override self-control mechanisms and thus to lead to addiction.” Nicole Avena, an expert in behavioral neuroscience at the University of Florida in Gainesville, has spent many hours analyzing the behavior of rats enticed into sucking up sugar. She says that feeding on sugar can, like snorting coke, lead to bingeing, withdrawal, and craving. It does this by lighting up the same circuitry within the brain triggered by cocaine and amphetamines, the dopamine center.

But a carbohydrate addiction is potentially more destructive than an 8-ball-a-day habit, because it hijacks your metabolism. If you eat a low-carb diet, you are able to remain satiated between meals, because the body will burn its fat stores. But eating carbs, especially refined varieties like sugar or flour, sweetened drinks, or starches, causes the body to release the hormone insulin. The body secretes insulin as a response to high blood sugar—a serious, even potentially lethal health risk over time. The hormone directs cells to extract sugar from the blood and store it as fat, and what’s worse, in order to get sugar out of the blood as efficiently as possible, insulin makes it extremely difficult for the body to burn its fat stores.

Over time, the presence of insulin in our carb-heavy diet causes diminishing returns. As our cells become resistant to the effects of insulin, our bodies frequently release even more of it to compensate. The result is a blood-sugar vacuum: The body craves more of what the hormone feeds on and triggers our hunger mechanism, which works subconsciously, to direct us toward the nutrient causing all the problems in the first place—carbohydrates. You get fatter and your body craves even more carbs in order to maintain your increasing weight. Drug cartels can only dream of a narcotic with an addiction cycle this powerful.

By Paul John Scott For Details.com

Marijuana is one of the less potent psychoactive drugs. It causes euphoria, disassociation and hunger. It can also cause your thought processes to become one long string of internal consistency moments (which may or may not be remembered once the effects wear off). Even very high doses won’t cause hallucinations in 99%   of the population. 

You wouldn’t know this from the common media representation of the drug. 

Teachers, parents, church officials are continuously tricked or cajoled into smoking up, or more likely eating a pot brownie. Five minutes later, they’re riding a unicorn through a rainbow, or arguing with the plants, or being chased by musical notes as if they’ve actually taken a powerful hallucinogen.

In this universe, marijuana is LSD. But why?

It seems to be based on the issue of creating a PG-rated drug experience. Mainstream writers, along with concerns of meeting broadcast standards, generally feel skittish about having their character use hard drugs. The resulting strategy is to either use an unnamed “substance” or depict a named drug, but with ridiculously overblown effects.

Even when the effects of LSD are shown, they are also powerfully overstated. On low doses, characters will experience detailed hallucinations and Daliesque delusions, when in reality a single tab of LSD will usually only give someone slight visual distortions that are easily distinguished from reality.