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One Major Side Effect of Drinking Coffee Every Day, Says Science

There’s a reason we love java so much, but we have to be careful!

It should be obvious, right? The one major side effect of drinking coffee every day is also likely the reason you started drinking coffee in the first place—to feel awake. The caffeine in coffee helps to wake up your body and make you feel alert throughout the day. According to Queensland Health, caffeine in coffee can improve energy levels as well as your memory, mood, and various brain functions.

Although caffeine usually gets a bad rep, there's actually a lot of good that can come from drinking it on a regular basis. One study published by the journal Longevity & Healthspan says that caffeine can actually help extend your life, improve your health, and can even delay age-associated diseases like Alzheimer's. It can even help you stay on track with your healthy diet goals, and reduces insulin signaling. According to a journal published by PLOS Biology, reduced insulin signaling can help protect your body against age-associated decline and extend your lifespan.

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And yet, while this major side effect of drinking coffee is probably the main reason we like coffee in the first place (besides tasting rich roasted beans from around the world), if we're not careful, this major side effect could also cause some damage to our bodies. The main way it can do so? If we drink too much coffee on a regular basis.

So how much is too much? According to the Mayo Clinic, every person is allowed up to 400 milligrams of caffeine on a daily basis. Since an average 8 oz. cup of coffee has around 100 milligrams, that means you're allowed to have four cups of caffeinated coffee on a daily basis before seeing any negative side effects! If we do the math, that's 28 oz. of coffee a day, which is just a little over a 20 oz. Venti coffee at Starbucks.

While four cups of coffee sounds like a lot, it can be easy to go over the recommended amount of caffeine a day—especially if you're also including other caffeinated beverages into your diet, like tea or even soda.

Overdoing it on caffeine can cause a slew of negative side effects on the body. One of the most crucial is intense feelings of anxiety and nervousness, which most people refer to as the "coffee jitters." Plus, the Mayo Clinic also points out that too much caffeine can cause frequent headaches, insomnia, nervousness, irritability, frequent urination, fast heartbeat, muscle tremors, and much more.

Healthline points out that drinking more than 1,000 milligrams of caffeine will absolutely trigger increased anxiety and cause insomnia issues, and will even create digestive issues. If your caffeine intake is happening later in the day, it can absolutely have an effect on your sleep patterns, which will affect your alertness in the morning…and likely have you drinking even more caffeine than you usually would. Causing that ugly cycle to happen all over again.

So, should you drink coffee at all? Absolutely. As we mentioned, drinking caffeinated coffee can improve your energy levels, makes you feel good, and gets your brain going in the morning. The key is to cap your coffee at four cups (28 oz.) and to keep the added sugars at a minimum. If you do that, you'll be reaping the positive benefits of caffeine, which is our absolute favorite side effect of drinking coffee every day!

Keep your coffee skinny with these 5 Ways to Make Coffee for a Flat Belly!

Kiersten Hickman
Kiersten Hickman is a freelance health and nutrition journalist. Read more about Kiersten
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