Beta-endorphin is one of a number of endogenous opioid peptide neurotransmitters. It is an agonist of the brain’s opioid receptors. When these receptors are activated, the body’s central nervous system is depressed, which lessens the body’s perception of the overall amount of pain. It is also speculated to be a fundamental neurotransmitter and as important as noradrenaline, serotonin, and dopamine to the function of the brain.
Found in the hypothalamus and the pituitary gland, these neurotransmitters are released during acute trauma such as breaking your leg or undergoing long-lasting physically strenuous activity. When the body is stressed, endorphins are released through the nervous system into the spinal cord. Unlike other types of endorphins, beta-endorphins can cross from the bloodstream to the brain. Here, they act as analgesics, helping the body and brain deal with the pain until it subsides.
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The experience of pain is different for everyone. Some people have higher tolerances than others. The amount of endorphins released by different activities is naturally different for each person. The more endorphins in the body, the more pain relief felt.
As pain increases, so does the beta-endorphin released into the bloodstream and the brain. There are stories of people performing what seem to be unnatural feats during times of stress. Feats such as a mother lifting an automobile off of her child trapped underneath are attributed to the amount of beta-endorphin rushing through their bodies. Studies have shown that beta-endorphin plays a role in all kinds of physiological behaviors. These include stress, alcoholism, obesity, mental illnesses and diabetes.
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Stress and pain are the two main instances of endorphins being released in the body. Others include intense exercise, acupuncture, childbirth and eating foods loaded with capsaicin. Light to moderate drinking can also induce an endorphin release, though heavy drinking will not.
Long-distance and marathon runners attest to a peaceful feeling — the “runner’s high” — when pushing their body to a higher performance level. As runners exert themselves, beta-endorphins are released and attach themselves to the limbic and prefrontal areas of the brain associated with pleasurable strong emotions such as romantic love. This gives the runner a heightened sense of euphoria and emotion that only comes when they run.
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Beta-endorphin is not physically addictive. Unlike exogenous opiates such as codeine and morphine, beta-endorphin is almost immediately absorbed by the opioid receptors to which it binds. Opiates are resistant to absorption and, therefore, the pain relief lasts longer than it would naturally. This resistance can lead to dependence on the drug to sustain the relief.