We all love to drink coffee, we used to drink it every day when we wake up to start the day. But you will absolutely not love the negative effects that coffee can bring to you. Caffeine acts as a stimulant by activating the central nervous system. It can fight tiredness and improve concentration and attention. According to the University of Michigan Health Services, caffeine's stimulant effects can begin as early as 15 minutes after consumption and last up to 6 hours. In addition to espresso, caffeine is regularly consumed through tea, carbonated soft drinks – especially caffeinated beverages – and chocolate. It is also found in some medicines and medications not approved by doctors, such as ice cream, sensitivity medications, and painkillers. Additionally, with so much research stating that caffeine consumption can benefit our health, and considering the amount of items that contain the stimulant, it's not a big surprise that caffeine consumption is so widespread. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay According to Medical News Today. Steven E. Meredith, a postdoctoral researcher at the Johns Hopkins University School of Medicine, says that, perhaps because of widespread consumption, many of us forget that caffeine is a psychoactive substance, a drug that crosses the blood-brain barrier to stimulate the central nervous system. He said: “Unlike most other psychoactive substances, caffeine consumption is socially acceptable and the drug is widely used. In fact, caffeine is the most commonly used psychoactive substance in the world. Furthermore, the vast majority of consumers of caffeine uses the substance regularly without apparent harm. These factors likely contribute to the prospect that caffeine is a benign substance that everyone can use without suffering negative consequences "Given the positive effects that caffeine can have as a stimulant, Meredith revealed to Medical News Today that for some people this can lead to caffeine addiction: "Caffeine activates many of the same behavioral and neuropharmacological mechanisms that are activated by other enhancers, including other drugs of abuse. And, like many other enhancers, caffeine it is associated with various positive subjective effects such as increased well-being, sociability and the feeling of energy and alertness. For this and other reasons, a small percentage of the population develops caffeine use disorder. "He said that some people can become physically dependent on caffeine, and the absence or decrease in coffee consumption leads these people to caffeine withdrawal. This can trigger manifestations such as migraines, weakness, depression, irritability, difficulty concentrating, nausea and vomiting. “The addiction can become so strong for some individuals that they are unable to reduce consumption despite being aware of recurring physical or psychological problems associated with continued use,” Meredith added. Metabolism is slower among infants, pregnant women and individuals with liver disease. Additionally, some medications slow the metabolism of caffeine, which can increase the risk of caffeine intoxication. But the effects of caffeine also vary simply because we are all different," he added. Coffee is bad for your health. But don't worry, because worrying is also bad for your health.