Caffeine is the most popular drug in the world with a long and rich history, and no single molecule has enriched our culture like the wondrous little 1,3,7-trimethylxanthine.

It’s also a controversial drug as various “experts” like to claim even mild but regular use eventually fries your nervous system, hurts your heart, and flatlines your adrenal glands.

I’m not sure how many people would give caffeine up if this these claims were true–it’s just too damn good–but fortunately for us “users,” they’re either exaggerated or wholly false.

While abusing caffeine can cause health issues, this is harder to do than you might think, and as you’ll see, consuming moderate amounts of caffeine regularly can actually improve your mental and physical health with no side effects whatsoever.

Let’s start at the beginning, though, with what caffeine is and how it works its magic in our bodies.

What is Caffeine and How Does It Work?


The modern way to start the day.

To understand the caffeine molecule and its effects in the body, we first need to understand what it banishes: the feeling of drowsiness.

This slow, sleepy stupor is caused by a molecule called adenosine, which is produced as your cells burn through energy stores, and which binds to receptors on neurons and tells your brain to slow down its signaling functions. The more energy you burn, the more adenosine you produce, and the sleepier you get.

Caffeine’s real magic is in its chemical structure, which is so similar to adenosine that nerve cells can’t tell the difference and allow it to bind to its adenosine-receptors.

Once caffeine has hijacked adenosine’s “seat” on a nerve cell, the fun begins. Instead of slowing down the central nervous system like adenosine, caffeine speeds up signaling processes, and the sudden spike in nervous activity causes your body to think there’s an emergency and to enter “fight or flight” mode.

Next in the sequence is the chemical that gives us the glorious caffeine “buzz”: good ol’ adrenaline, which follows the false alarm. Our pupils dilate, our heartbeat increases, our livers start releasing sugars, and we lap it all up.

So that’s how caffeine works, but an understanding of the mechanism raises a question: jolting our nervous system with chemical uppers every day has got to be unhealthy, right?

Common sense would say that sooner or later, regular consumption of this awesome little drug is going to catch up with us and our poor, abused neurons; that every glorious milligram ingested brings us a little bit closer to the reckoning. Many health “experts” say the same.

Well, I have good news: caffeine isn’t the dietary equivalent of unprotected sex or texting while driving. Much of the criticism leveled against it is bunk, and when used sensibly, it can even improve your health.

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4 BS Caffeine “Side Effects” Debunked by Science


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Caffeine is a drug so some people are naturally more sensitive than others, but it’s not nearly as dangerous or harmful as many people would have you believe.

If you’ve been told to stay away from caffeine, it’s probably for one or more of the following reasons. Let’s put these myths to bed.

BS Side Effect #1:
Caffeine is Addictive

Although you may feel “addicted” to your cup of Morning Mud, chances are you’re not.

Abruptly eliminating caffeine from your diet can cause mild withdrawal symptoms for a day or two, such as headache, fatigue, and regular use may cause mild physical dependence, but for most people caffeine isn’t addictive in the way that alcohol and street drugs are.

Quitting doesn’t turn you into a monster and you’re not going to pawn stuff pilfered from your grandma’s house to buy that next latte, so you can caffeinate with a clear conscience.

BS Side Effect #2:
Caffeine Causes Insomnia

It’s fair to assume that chemically supercharging your nervous system every day is going to mess with your sleep, but that’s not always the case.

Research shows that regular caffeine use can impair the length and quality of your sleep, but these effects vary from person to person as some people’s bodies are better at processing the drug than others and the effects are smaller in habitual users than occasional.

What this boils down to is if you’re like most people, stopping caffeine intake at least 6 hours before bed will prevent sleep disturbances.

Unless your body is extremely sensitive to caffeine, your morning coffee or pre-workout simply isn’t going to affect your sleep. 

BS Side Effect #3:
Caffeine Increases the Risk of Osteoporosis, Heart Disease, and Cancer

Caffeine and Osteoporosis

At fairly absurd high levels of intake (more than 744 milligrams per day), caffeine may cause increase calcium and magnesium loss, but this is a non-issue because the calcium lost from drinking a cup of coffee can be replaced with two tablespoons of milk.

This is why research has shown that caffeine intake ranging from 0-1,400 milligrams per day (!?) has no effect on bone density. If you get enough calcium in your diet, caffeine won’t weaken your bones.

Caffeine and Heart Disease

Caffeine acutely raises heart rate and blood pressure and thus was assumed to increase the risk of heart disease. Research says otherwise, though.

According to the findings of the Nurses’ Health Studies I and II, which involved over 162,000 subjects and 26 years of data, and those of another long-term study carried out on 128,000 people over a period of 14 to 20 years,  coffee consumption–even at high levels–has no effect on blood pressure levels.

Soda intake was associated with higher blood pressure levels, though, implying that something other than caffeine was the cause.

Caffeine and Cancer

Research shows that caffeine is unlikely to be carcinogenic at intakes of less than 500 mg per day, and that it may even help protect against certain kinds of cancer.

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The Bottom Line on Caffeine and Disease

To quote researchers from the Canadian government’s Bureau of Chemical Safety:

“Based on the data reviewed, it is concluded that for the healthy adult population, moderate daily caffeine intake at a dose level up to 400 mg day(-1) (equivalent to 6 mg kg(-1) body weight day(-1) in a 65-kg person) is not associated with adverse effects such as general toxicity, cardiovascular effects, effects on bone status and calcium balance (with consumption of adequate calcium), changes in adult behaviour, increased incidence of cancer and effects on male fertility.”

BS Side Effect #4:
Caffeine Dehydrates You

Caffeine does have a mild diuretic effect, but research shows that the amount of liquid contained in a caffeinated beverage is enough to replace the amount lost.

Research also shows that a caffeinated beverage is effective for fluid replacement during exercise.

4 Scientifically Proven Benefits of Caffeine


Hitler loved decaf coffee. Need I say more?

Now that we’ve cleared the road of debris, let’s get to the fun stuff: why we should continue drinking caffeinated beverages and eating chocolate.

Caffeine Benefit #1:
Caffeine Improves Exercise Performance

Want to have better workouts? Have some caffeine beforehand.

Research shows that caffeine improves strengthmuscle endurance, and anaerobic performance, and also reverses the “morning weakness” experienced by many weightlifters.

If having better workouts is your kind of thing, then there are a few molecules in addition to caffeine that have been scientifically proven to help, and you’ll find them in my pre-workout drink PULSE.

It contains 6 of the most effective performance-enhancing ingredients available:

And what you won’t find in PULSE is equally special:

  • No artificial sweeteners or flavors..
  • No artificial food dyes.
  • No unnecessary fillers, carbohydrate powders, or junk ingredients.

The bottom line is if you want to know what a pre-workout is supposed to feel like…if you want to experience the type of energy rush and performance boost that only clinically effective dosages of scientifically validated ingredients can deliver…then you want to try PULSE.


Caffeine Benefit #2:
Caffeine Helps You Lose Fat

Caffeine speeds up your body’s metabolic rate by increasing the amount of catecholamines in the blood, which are chemicals that mobilize fat stores to be burned for energy.

Caffeine is a safe, effective weight loss aid that I highly recommend to anyone wanting to lose fat.

Caffeine Benefit #3:
Caffeine Improves Mental Performance

Want to know “one weird trick” for instantly becoming smarter?

Research shows that caffeine is an effective cognitive enhancer: it improves alertness, psychomotor learning speed, memory, reaction times, and focus.

Caffeine Benefit #4:
Caffeine Improves Mood

The research is clear: a few hits of caffeine per day keeps the head doctor away.

Studies show that caffeine enhances mood and that depression is lower among people that drink coffee or tea regularly.

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How Much Caffeine Should You Have?

For most us, the question isn’t whether we should have caffeine or not, but how much.

Most of caffeine’s benefits are seen in the range of 200 to 400 mg per day, and an extensive review of caffeine research concluded that intake shouldn’t exceed 6 mg caffeine per kg of body weight per day (about 400 mg for the average person).

If you’re curious how much your favorite caffeinated beverages actually contain, look them up in this database.

If you’re taking caffeine to increase physical performance, and you want to keep it maximally effective, you want to prevent your body from building up too much of a tolerance. The best way to do this is to limit intake. Here’s what I recommend:

Before training, supplement with 3 – 6 mg caffeine per kg of body weight. 

If you’re not sure of your caffeine sensitivity, start with 3 mg/kg and work up from there.

Keep your daily intake at or below 6 mg per kg of body weight. 

Don’t have 6 mg/kg before training and then drink a couple of coffees throughout the day.

Do 1 – 2 low-caffeine days per week, and 1 no-caffeine day per week. 

A low day should be half your normal intake, and a no day means less than 50 mg of caffeine (you can have a cup or two of tea, but no coffee, caffeine pills, and so forth. Using a stimulant-free pre-workout on no-caffeine days can also help keep your intake low).

The Bottom Line

The research is clear: when used sensibly, caffeine is pretty awesome and well deserves its place in our hearts (and adenosine-receptors).

Unless you’re particularly sensitive to its effects, there’s just no reason to not enjoy your coffee, tea, chocolate, or pre-workout drinks regularly.

+ Scientific References