Subtitles section Play video Print subtitles We've all been there before. It's 3 a.m. It's late. And you're preparing for an exam the next morning. Attempting to cram as much last minute information into your brain as possible. The only way to stay up and not fall asleep? Red Bull! But as every minute passes, and every fresh can of that delicious energy drink is cracked open, is it too much? Can it be too much? Can you overdose on caffeine? Caffeine is a natural stimulant that affects the brain and central nervous system. It helps prevent onset tiredness, and keeps us generally more alert. Caffeine's primary function is on the brain. Once it hits your gut, it enters your body and blood stream relatively quickly. Adenosine is a neurotransmitter in the brain that makes us feel tired, and relaxes us. But once caffeine reaches the brain, it will connect the adenosine without activating it. So, basically we don't get tired when we should. We feel more awake, stimulated, and focused at a time when we might otherwise feel tired. Because Caffeine enters the body and bloodstream through the gut, it usually kicks in pretty fast. The amount of caffeine found in one cup of coffee generally takes twenty minutes or less to take effect. A can of Red Bull can actually begin making us feel more alert in as little as 15 minutes. So, when is too much? It's generally accepted that up to 400 milligrams of caffeine is healthy and safe. That's roughly 4 cups of coffee. To put things in perspective, a single 8oz serving of chocolate milk contains 2-7 milligrams of caffeine. Decaf Coffee contains 3-12 milligrams . Soft drinks contain 20-40 milligrams. Brewed Tea has 40-120 milligrams. Energy drinks like Red Bull, have 50-160 milligrams, while coffee and espresso can have between 120-720 milligrams of caffeine! Doctors say if you intake over the accepted 400 milligrams of caffeine you can expect to start having some serious side effects. Those might include migraines and headaches. Nervousness. Increased heart rate. Upset stomach. Muscle tremors. And insomnia. Okay, so those are the general symptoms that might begin to take effect. But what really happens as you progressively drink more? Starting with one Red Bull, which represents roughly one cup of coffee, most consumers say they feel more awake, aware, and very functional. You may feel ready to take on a list of chores, or do extra work. Maybe even stay up studying for a few more hours! Now, let's say things have escalated. It's getting later and you reach 20 Red Bulls. That's nearly 1600 milligrams of caffeine! In Europe, a young woman used to drink nearly 20 cans of Red Bull each day. The repercussions were severe. Her liver was nearly destroyed, and she gained an enormous amount of weight, jumping from a size 14 to a size 22. Not to mention her bank account was also hurting. Even when you buy Red Bull in bulk, 20 cans a day for an entire year is roughly 8680 USD. That's a lot of money! Let's just say for fun that things get really bad and you consume 100 Red Bulls. That's nearly 8,000 milligrams of caffeine. This is serious health problem territory. Effects now escalate to seizures, strokes, and even hallucinations! In 2012, a user posted a review of Five Hour Energy drinks claiming he had consumed 22 Five Hour energy bottles all poured into a Big Gulp cup and consumed in a very fast time frame. He said he hadn't been able to sleep in over 72 hours, no longer could feel his own pulse and was suffering from hallucinations! Now the big question: What would happen if you consumed 1000 Red Bulls? Really bad things. Even if you could get past the severe dehydration that would probably occur early on, and the numerous other health problems that would manifest pretty early, most likely you would have severe heart palpitations that eventually can and probably will lead to a stroke. Your bodies internal organs might slowly cease to function, including the kidneys and liver. And the possibility of death is serious, especially if you have a pre-existing health problems. In the end, caffeine isn't a complete evil. Some studies have shown that consuming a healthy amount of caffeine daily can actually help the body. It can improve brain activity and functionality, metabolism, and exercise performance. In some cases, doctors have found it may even help prevent heart disease and diabetes. But the overall effects caffeine produce are also subjective to each individual and based on their own body. Some people need more, some people need less, and some people don't even need it at all. The best bet with caffeine and energy drinks is to consume them at a safe, healthy level and not over do it. Always remember to hydrate in-between, and replenish your body with plenty of fresh water.