Bodybuilders are known for going to extremes for their physique. In some cases, as with injecting insulin, their methods can be dangerous or even fatal. Insulin, a hormone secreted by the pancreas, regulates the body's metabolism of carbohydrates and fat. Injections are meant for people whose bodies don't make enough insulin, like those with diabetes.

But sometimes, it's also injected by bodybuilders who are trying to bulk up and increase their endurance, according to an August 2015 review published in the Journal of Basic Clinical Physiology and Pharmacology. However, this is not safe and should not be attempted 6.

Warnings

Insulin is meant for people whose bodies don't make enough insulin, like those with diabetes. If you're bodybuilding (which lowers your blood sugar) and taking extra insulin (which also lowers your blood sugar), your risk of hypoglycemia multiplies, which can potentially result in a coma or death. Do not take insulin unless your doctor has prescribed it to you.

How Does Insulin Work in Bodybuilding?

When you eat, your body processes carbohydrates in food into glucose, known as blood sugar.

Insulin helps get the glucose out of your bloodstream and into your cells, where it's used for energy. It also regulates the amount of glucose in your blood, keeping blood sugar levels from getting too high.

**So how does insulin build muscle?

** It's an anabolic hormone, which means it promotes muscle growth and muscle storage. It also stimulates glycogen formation, which feeds the muscles and increases muscle mass.

This is why some bodybuilders try to use insulin to get bigger muscles. But using insulin to enhance bodybuilding is not recommended, as it come with a number of potentially fatal health risks.

Insulin overdose "puts the user at risk of developing hypoglycaemia [low blood sugar] for prolonged periods... potentially resulting in coma and death," according to a 2003 case report from the British Journal of Sports Medicine. And a March 2019 clinical report published in the Journal of Emergency Medicine describes the case of a bodybuilder who fell into an insulin-induced coma.

It should also be noted that the International Olympic Committee only permits athletes who use insulin to manage their diabetes to use insulin. All other use is prohibited.

Read more: 3 Essentials for Becoming a Body Builder

  • When you eat, your body processes carbohydrates in food into glucose, known as blood sugar.
  • Insulin helps get the glucose out of your bloodstream and into your cells, where it's used for energy.

Dangers of Abusing Insulin

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Insulin lowers blood sugar.

When blood sugar levels fall below the normal range, it's known as hypoglycemia.

The typical symptoms of hypoglycemia are hunger and irritability. Most people know these symptoms well; they are the classic signs that you're "hangry" and your body needs more fuel.

For people relying on their body's natural insulin, these symptoms don't generally worsen because the body has a backup system — a group of five counter-regulatory hormones that use the body's reserve supply of glucose to re-raise blood sugar.

But if people who already have enough insulin inject more, their backup system can be overrun: The extra insulin can remove too much glucose from their blood. This can have very serious consequences, including life-threatening hypoglycemia.

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  • Insulin lowers blood sugar.
  • For people relying on their body's natural insulin, these symptoms don't generally worsen because the body has a backup system — a group of five counter-regulatory hormones that use the body's reserve supply of glucose to re-raise blood sugar.

Exercise Can Worsen Insulin-Induced Hypoglycemia

Another factor that makes insulin-intensified bodybuilding extremely risky is that bodybuilding is exercise, and exercise lowers the body's blood sugar levels 3.

Muscles need more glucose when they're active, so the body's ability to use insulin improves during exercise 3. Cells become more sensitive to the insulin, absorbing glucose from the bloodstream more easily.

In other words, if you're bodybuilding (which lowers your blood sugar) and taking extra insulin (which also lowers your blood sugar), your risk of hypoglycemia multiplies.

Jacqueline Shahar, certified diabetes educator and manager of the clinical exercise physiology department at Harvard's Joslin Diabetes Center, strongly discourages insulin-enhanced bodybuilding.

"The concern is that insulin will bring the blood glucose down and [the bodybuilder] can end up with hypoglycemia," she says. "That could be fatal."

The dangers of life-threatening hypoglycemia aren't the only drawback to using insulin to enhance bodybuilding 7. Insulin injections can also make the body gain fat, making it even harder to sculpt the muscles that are the bodybuilder's goal in the first place 5. (Insulin helps the cells take in glucose, which store any excess glucose as fat.)

Read more: How Exercise Affects Human Growth Hormone Release

  • Another factor that makes insulin-intensified bodybuilding extremely risky is that bodybuilding is exercise, and exercise lowers the body's blood sugar levels 3.

Symptoms of Hypoglycemia

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The symptoms of insulin spike-induced hypoglycemia can progress very quickly. Here's what to watch out for, according to the American Diabetes Association (ADA) 13:

  • Hunger 
  • Irritability
  • Feeling shaky
  • Feeling nervous or anxious
  • Feeling sleepy
  • Feeling weak or having no energy
  • Sweating, chills and clamminess
  • Confusion
  • Blurred or impaired vision
  • Tingling or numbness in the lips, tongue or cheeks
  • Clumsiness; coordination problems
  • Nausea
  • Pallor (looking pale)
  • Fast heartbeat
  • Seizures
  • Loss of consciousness

Warnings

If left untreated, severe hypoglycemia can be fatal. If you experience any of the above symptoms, especially after taking insulin, seek immediate medical attention.

It is extremely risky to use insulin without medical supervision and for reasons other than the treatment of an insulin-related disorder such as diabetes. Illicit insulin use may result in death.

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