July 16, 2021 4 min read

A lot of us aren’t really sure exactly how caffeine works, but we’ve been told that it’s not exactly great for us. So…why do we still go for it?

That glorious boost of energy.

For a while, my morning cup of coffee was a habit I was trying to break. But it was a hard part of my routine to ditch – I’m normally reaching for my coffee maker before I even go for a glass of water every morning. 

And apparently, that’s pretty normal. 90% of adults consume caffeine daily in North America.

When I decided to write this blog post, I was certain that doing so would solidify my resolve to fight against my caffeine intake. But after learning more…I’m not so sure I want to give it up anymore.

How Does Caffeine Work?

Let’s take a look at the science.

After caffeine is consumed and absorbed into the bloodstream, it gets to work on its main job: blocking the neurotransmitter adenosine. And what does adenosine do?

It tells your body that you’re tired.

In a body without caffeine present, adenosine levels build up throughout the day, making you more and more tired until you finally decide to nap or go to bed.

However, caffeine blocks the effects of adenosine. In fact, it might even increase brain activity of dopamine and norepinephrine, as well as raise blood adrenaline levels – a combination that leads to a faster heartbeat and an improved mood, making you feel more alert.

If that all sounds like the effect of a drug, it’s because it is. Because caffeine directly affects your brain, it’s sometimes categorized as a psychoactive drug. It’s easy to forget that we’re legally consuming a psychoactive drug almost every single day. And a lot of us tend to consume quite a bit…even enough to experience low-level withdrawal symptoms when we go without (ever had a headache because you didn’t drink coffee that morning?).

Is Caffeine Healthy?

Despite its “drug” classification, the research seems to be saying…yes. (Woohoo!)

Health benefits of caffeine include:

  1. Mental Health and Brain Function

We’ve discussed how caffeine blocks adenosine and increases levels of dopamine and norepinephrine. This switch can change the way your brain functions, improving alertness, short-term memory, and mood.

And it’s no small change.

When it comes to mental health, one study linked 2-3 cups of coffee (200-300mg) a day to 45% lower risk of suicide, and another found 13% lower risk of depression. And in the arena of brain function, 3-5 cups of coffee or 3+ cups of tea per day may reduce the risk of Alzheimer’s and Parkinson’s by 28-60%. (However, some of these benefits might be connected to the other beneficial bioactive components found in coffee and tea.)

  1. Metabolism Boost

Consuming 300mg of coffee a day can help you burn an extra 79 calories/day. So no, coffee won’t help us lose significant amounts of weight. But that 79 calories a day can offset the average 2.2 pounds of yearly weight gain most American adults see annually.

  1. Better Workouts

When consumed an hour before exercising, caffeine can help make your workouts better. Caffeine makes the glucose stored in the muscles last longer, which can help you exercise with more intensity for an extended period of time.

  1. Cardiovascular Health

Caffeinated beverages – despite common misconceptions – can actually lower the risk of heart disease (by 16-18%!) and type 2 diabetes.

It’s important to note that this can vary by person. Some people are more sensitive to caffeine, and it can raise their blood pressure a small amount. However, for most, this increase in blood pressure goes away with more regular consumption.

More studies are being conducted on caffeine’s effects on longevity, damage protection, and disease prevention (and the early findings are lookin’ good!).

How Much is “Too Much” Caffeine?

Okay, okay. All these great benefits don’t mean we can replace every beverage with our favorite caffeinated drinks. (Here’s your reminder to drink some water!)

The USDA has declared 400mg of caffeine per day to be safe for most adults. (Read: 2-4 cups of coffee, spread throughout the day.) In general, you’d want to split the daily intake into two 200mg doses. In some cases, 500mg all at once has led to an overdose.

Pregnant women should aim for under 200mg/day, and people taking certain medications like Zanaflex (muscle relaxant) and Luvox (antidepressant) should avoid caffeine, as it increases their effects.

Important note: caffeine can cause “jitters” that increase anxiety, and it can also act as a diuretic. If caffeine is making you feel ill or uncomfortable, decrease your intake.

How Much Caffeine Am I Consuming?

Not sure how much caffeine you’re taking in each day? Let’s break down our most-consumed drinks:

  • Coffee: 100-200mg
    • Venti caramel macchiato is 150mg (my go-to Starbucks order), while Americanos and drip coffee tend to be 95-200mg.
  • Espresso: 240-720mg
    • Starbucks Doubleshot Espresso (6.5oz can) has 120 mg of caffeine.
  • Energy drinks: 50-160mg
    • Bang energy drinks have 300mg caffeine per can, while Red Bull has 111mg.
  • Soft drinks: 20-40mg
    • Dr Pepper and Diet Coke have about 43mg in 12 oz. (But note that most bottles are 16.9oz.)
  • Tea
    • Brewed green tea has 29mg per 8oz while brewed black tea has 47mg.

Other Sources of Caffeine Consumption

Of course, we knew our drinks had caffeine. But did you know that ourfood can contain caffeine as well?

While granola bars, yogurt, and cereals can give you small amounts, other foods like ice cream – and anything containing chocolate – can provide fairly substantial doses. (Those coffee-flavored Cliff Bars? 70mg of caffeine!)

Last up: OTC medications. Lots of pain relievers contain caffeine. It tends to make those medications more effective and helps the body absorb them more easily.

For a rule of thumb, Excedrin Migraine and Midol Menstrual Maximum Strength Caplets have around 60mg while Bayer Back & Body has just over 30mg. 

Wherever you get your caffeine, remember to try to stick to that rule 400mg or less a day and talk to a nutritionist if you need help or are concerned about your diet.

Cassandra Pulos
Cassandra Pulos