How Much Caffeine Is Too Much?

Caffeine in moderation has its perks like increased alertness, but knowing when to stop can protect your health.

Mornings are a time for fresh starts and new beginnings. And there’s no better time for that first sip of coffee — at least for two-thirds of Americans, according to the National Coffee Association.

In moderation, caffeine — a natural stimulant — has its perks like increased energy, alertness, concentration and a better mood. There are even studies that suggest potential heart health benefits and lowered blood pressure.

But if that cup of coffee is the first of many, could you be overdoing it? Whether you’re getting caffeine from coffee, soda, energy drinks or dietary supplements, too much caffeine could give you the jitters rather than a jolt.

“Caffeine can be a part of a healthy diet, especially when it’s consumed in moderation,” says Thomas Nawrocki, PA-C, a physician assistant at Geisinger Family Practice Montage. “Everyone reacts differently, but consumption above 400 mg is typically when people feel the side effects and it starts to negatively impact health.”

That might seem like a lot, but energy drinks and store-bought coffee can contain half of that in a single serving. To determine how much caffeine is too much for you — and when you’re crossing the line into unhealthy territory — document your intake and observe how you feel.

What are the side effects of too much caffeine?

Everyone hits a midday slump on occasion. Whether that comes from lack of sleep or an exhausting schedule, you may be tempted to grab a cup of coffee or energy drink to power through. But overdoing it could leave you feeling nervous, paranoid or agitated.

The side effects of caffeine in excess include:

Jitters
Shakiness
Anxiety
Fast heart rate
Upset stomach and nausea
Sleeplessness
Paranoia
Agitation

“Because caffeine is a stimulant, it increases levels of serotonin and norepinephrine,” says Mr. Nawrocki. “In moderation, you can feel alert and acute euphoria. But if you overdo it, you’ll feel anxious and possibly sick.”

Keeping track of how you feel after having caffeine is the first step to knowing your limits. While the FDA suggests having less than 400 mg daily (equivalent to about 4 cups of coffee), it may only take 1 cup of coffee for you to feel the same way as someone else who drinks 6 cups. It affects everyone differently, depending on factors such as body weight, health status, current medications and a sensitivity to caffeine.

Is caffeine overdose a real thing?

If you’re drinking coffee, soda or energy drinks, a caffeine overdose is highly unlikely. You’d have to drink about 28 cups of brewed coffee to reach those dangerous levels.

However, you should use caution with caffeine powder and supplements. The caffeine in 28 cups of coffee is equal to 1 teaspoon of pure caffeine powder.

“Caffeine powder is often used in athletic circles or marketed as a weight-loss supplement,” says Mr. Nawrocki. “Pay attention to how much you’re using and always consult your doctor.”

If you do use powder, make sure to clean up any spills. Children and animals are sensitive to caffeine, and even a small amount in powder form can be fatal if ingested.

And be sure to ask your doctor or pharmacist if any of your medications interact with caffeine.

“Caffeine is a drug, and it interacts with several commonly prescribed medications, including atomoxetine, bupropion, ciprofloxacin, clozapine, linezolid, lithium and tizanidine,” says Mr. Nawrocki. “Thankfully, moderate caffeine consumption — no more than 1 to 2 cups of coffee per day — is unlikely to lead to serious drug interactions.”

What has the most caffeine?

How do you keep caffeine consumption on the safe side? By moderating your intake. And it starts with knowing where you’re consuming caffeine.

Coffee

Eight ounces of brewed coffee has around 80 to 100 mg of caffeine, depending on the type of coffee and brewing method. While this doesn’t seem like a lot, its effects can add up as you have more cups throughout the day.

Energy drinks

Some popular brands of energy drinks have anywhere from 40 to 350 mg of caffeine per serving. Check the nutrition label to keep track of how much you’re consuming.

Tea

A cup of black tea typically has 30 to 50 mg of caffeine. Other varieties, like white or green tea, tend to have less.

Soda

Although it has less than a single cup of coffee, some cans of soda have 30 to 55 mg of caffeine.

Chocolate

Drinks are the typical caffeine culprits, but don’t forget chocolate. A bar of dark chocolate (roughly 100 grams) has about the same amount of caffeine as a cup of coffee. Dark chocolate has more than milk or white, and chocolate-flavored foods like cakes, cookies and brownies have less than actual chocolate.

“When adding up your caffeine intake for the day, be sure to include all sources, including chocolate and baked goods,” says Mr. Nawrocki. “It even can be in some medications for headaches.”

How to cut back without caffeine withdrawal symptoms

If you’re dependent on caffeine to stay awake or have adverse effects, look for a better way to stay energized throughout the day. There are plenty of options to cut back on caffeine without the unpleasant side effects.

“Whatever you do, don’t quit cold turkey,” says Mr. Nawrocki. “Your body is used to having caffeine, so when it doesn’t get it, you’ll get caffeine withdrawal symptoms like headaches, fatigue and agitation. Try reducing your intake gradually over weeks to allow your body to adjust.”

Many find cutting back over time an easy process, but you might still crave a warm cup of joe. While decaf coffee contains less caffeine, it still has about 2 to 15 mg per 8 ounces.

Another option is swapping coffee for tea. Herbal and fruit teas like peppermint, chamomile and lemon are naturally caffeine free. This can help you lower your intake while still having something to sip on.

“Coffee is tricky because it becomes a ritual,” says Mr. Nawrocki. “It’s usually how we start our day and can become an ingrained habit. I recommend tea for anyone trying to lower their caffeine intake. You can still have a little milk or sugar in your tea, and it gives you a moderate amount to start your day.”

Looking for a pick-me-up in the afternoon? Flavored or infused sparkling water with fruits and herbs can be a refreshing substitute for caffeinated sodas or energy drinks.

Reap the benefits, not the side effects

If you’re like most adults, caffeine is a part of your normal routine. But moderation, like in all aspects of life, is typically rewarded. While caffeine offers temporary energy boosts, excessive intake can have detrimental effects.

“Too much caffeine can increase anxiety, sleep disruptions and the risk of heart problems,” says Mr. Nawrocki. “If you have side effects after your morning cups of joe, lowering your intake can help to reap the benefits and not the unpleasant side effects that put your health at risk.”