How Much Caffeine Is Too Much? Safety Guideline Roundup

If you have already read a few of my earlier posts, you know that I am completely addicted to 2 things: coffee and science.

I love knowing the intimate details of how my coffee affects my body.

It brings the best out of me, to be perfectly honest.

The typical positive effects that we feel immediately include:

-Mood boost

-Mental alertness

-Increase in blood flow

The beauty of coffee is so much more than skin deep. There are medical benefits in every cup. Harvard School of Public Health says that it may reduce the risk of type 2 diabetes and heart disease/failure. An Italian doctor, Dr. Carlo La Vecchia, from Milan’s Istituto di Ricerche Farmacologiche Mario Negri, states that coffee is particularly good for the liver. Researchers at the University of Scranton state that a moderate amount of coffee taken on a daily basis is the number 1 source of antioxidants, a substance in food that protects oxygen from being mutated by toxins.

Sounds great, right?

Why would anyone choose to go without a mug full of medicinal, delicious coffee?

This is where it gets interesting…

Some people experience the exact opposite effect.

They feel the effects early on. They get nauseous, jittery, and anxious. They’re hearts palpitate and they start to sweat.

So what makes some people respond well to caffeine, while others should stay away entirely?

It’s all hinged upon one gene. The CYP1A2 gene communicates with your liver and determines how your body processes caffeine. Prescription or poison, pinned on this one factor.

It’s important to note that there are risks of consuming too much caffeine, even if your body can metabolize it quickly. Should you consume more than the recommended amount, you can experience the exact same symptoms of those who can’t process caffeine at a normal speed.

How much caffeine is too much?

The Mayo Clinic suggests that 200mg a day is the safest amount consumed. 400mg a day is relatively safe for the average adult, at the most. But that amount taken daily is dangerously close to the 500mg a day that Robert Glatter, M.D., an assistant professor of emergency medicine Northwell Health and Lenox Hill Hospital in New York, says is typically when things start to go awry.

What about caffeine tolerance?

Caffeine tolerance is the mutation of how your body feels when you have caffeine in your system. Tolerance builds as soon as 1-4 days. That’s why, the longer you drink coffee, the more you seem to need to feel that euphoric, pick-me-up feeling.

But tolerance has nothing to do with your sensitivity to it or whether you’ve had too much. It’s exactly the same as people who have high alcohol tolerance. They can drink a lot without feeling the adverse effects, but their body is reacting on a chemical level regardless.

According to healthresearchfunding.org just over half of the adult American population consumes coffee on a daily basis. Which sounds really innocent until you look at all the other ways we have caffeine, without really thinking about it.

Even caffeine in cute little pieces of chocolate served on the saucer of our lattes.

I’m not saying these things to scare you away from the beloved breakfast drink. We are a roaster, a blog, and an online shop, after all. As always, I am on a quest to educate you on the best ways to experience your coffee.

Let’s talk about how those measurements translate to the caffeinated beverages we love.

A standard cup of black coffee is equivalent to roughly 163mg of caffeine.

An espresso shot and a Red Bull contain the same caffeine about half of that, 80mg per 1.5 fl oz.

A soda has about 34mg per can, give or take, depending on brand.

Green tea is packed with solid nutrients, and contains about 25mg per cup.

And the infamous 10 hour energy shot contains a whopping 420 in that teeny 2 oz bottle.

Here’s a mind-blowing factoid!

Even decaf has caffeine content. Given it is a minuscule 6mg per 8 fl oz, It seems like we truly just can’t get away!

I personally have never run away from a hot cup of coffee or an ice-cold coke. But I experienced caffeine poisoning last week while writing the French press piece, and felt moved to write about it, so that we are all more aware.

I had the classic symptoms.

Nausea? Check. Didn’t leave my couch.

Sweating? Gross check.

Chills? Big check. Sweats, long socks and two blankets check.

Insomnia? Check. I twiddled my thumbs for 8 hours.

Stomach cramps? Check.

Unquenchable thirst? Check.

Muscle spasms? Check.

Weird heart palpitations? Check.

Maybe that sounds overdramatic but just last summer, a teenager in South Carolina died from heart palpations an overdose of caffeine. And his overdose started with the symptoms I know well.

He had an iced latte, an energy drink and a Mountain Dew. We can’t take his tragic story lightly.

In this age of fitbits and calorie counting, maybe it’s time that we become more take responsibility for our caffeine habit.

How long does caffeine stay in your system?

4-6 hours, depending how much is in your system, how much water you had, and how quickly your liver can metabolize caffeine. So during these 4-6 hours, we need to be sure that we do not go over that suggested maximum caffeine intake— 400mg.

A typical American consumption scenario

According to a Huffington post, 31% of the adult population living in the United States feel like a cup of coffee is absolutely necessary to behave normally.

65% of those people make their coffee in the morning, before they do anything else.

So let’s say you wake up at 7 o’clock in the morning. You sleepily make the first cup of coffee. That’s 163 mg of caffeine.

You get dressed and swing through a drive-thru coffee shack at 8 AM on your way to the office and get a 16 oz café latte. These typically come with a double shot of espresso. That’s 80mg times 2, 160mg.

You work through the first part of your day feeling all the awesome effects of your coffee. You’re morning mental fog is gone. You’re completing tasks easily.

Magically, it’s noon! Your morning flew by. You stop by a deli with a co-worker. You have a soda with your sandwich. That’s 34mg per can. And the colleague who joined you suggests grabbing a cup of coffee before you have to go back. 163oz… again.

In those 6 waking hours, you have consumed 520mg of caffeine, just above the aforementioned 500mg warning.

Just imagine if you had made 2 cups of coffee first thing, or had a quad café latte when you hit the coffee shop.

Our tolerance is strong almost unanimously as a culture.

We don’t really think about it. That’s how a good thing becomes dangerous.

The Aristotle wisdom is always appropriate, even for people like us who feel like there isn’t ever enough coffee.

“Moderation in all things.”

Brian Mounts

Head blogger, editor, and owner of "Top Off My Coffee", a website that has been educating readers about coffee brewing techniques and equipment since 2012.

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