Whether you use it for a morning pick-me-up or nurse it all throughout the day, caffeine is likely part of your routine in some way or another. But aside from knowing it helps you feel awake and alert, how much do you really understand about how caffeine works in your body? And do you actually know how much caffeine you’re drinking every day? This guide will help you get clear on those questions and highlight just how much caffeine nine popular beverages contain.

The Caffeine Basics

Caffeine is considered a chemical stimulant, explains The Vitamin Shoppe nutritionist Rebekah Blakely, R.D.N. It stimulates you by “blocking receptors in the brain for adenosine, which is a neurotransmitter that promotes relaxation,” she says. “Adenosine levels build while you’re awake throughout the day, leading you to feel sleepy by bedtime. When caffeine blocks those receptors, though, circulating levels of adenosine aren’t recognized by the brain, delaying fatigue.”

Read More: 5 Signs You Need A Break From Caffeine

There are two forms of caffeine in the drinks many of us guzzle: natural and synthetic.

“Natural caffeine is found in plants like tea leaves, coffee beans, and cacao beans, and is used in teas, coffee, chocolate and chocolate beverages, and cola,” says The Vitamin Shoppe nutritionist Roseanne Schnell, C.D.N. “Synthetic caffeine, meanwhile, is man-made and added frequently to supplements, OTC medicines, foods, and beverages.”

Despite the different origins and applications of natural and synthetic caffeine, the two have the same effects in the body, Schnell notes.

How Much Caffeine Is Best For You?

The general guideline for caffeine consumption is that adults consume less than 400 milligrams total per day. 

“This amount has been shown to be relatively safe for most individuals,” Blakely says. “However, every person has a different tolerance. Some people are highly sensitive to caffeine, and may notice negative effects—like jitters, increased anxiety, heart palpitations, headaches, and sleeplessness—from even small amounts.”

Read More: 6 Ways To Conquer The Mid-Afternoon Slump Without Caffeine

Experiencing negative effects is reason enough to reduce your daily caffeine intake, but there are other groups of people who should be extra mindful about their intake, including:

• Pregnant women, who should consult with their doctor, since studies have shown that excessive intake may affect fetal development
• Breastfeeding women, since some babies may be sensitive to trace amounts that make it into breastmilk
• Those with anxiety, who may notice worsened symptoms after consuming caffeine
• Those with digestive/bladder issues, who may find the digestive or bladder stimulation that caffeine causes bothersome
• Those with heart problems, since caffeine can increase heart rate and blood pressure

Specific health concerns and needs aside, Blakely recommends all people try to cut off caffeine consumption after two o’clock in the afternoon, since it can take eight-plus hours to completely clear out of the body and potentially impact sleep when consumed later in the day. 

How Much Caffeine Popular Drinks Contain

Different popular beverages contain different amounts of caffeine, meaning that some might be more appropriate options for certain people or scenarios. In fact, even for those who tolerate caffeine well, Blakely recommends cycling between days of higher consumption, days of lower consumption, and completely caffeine-free days.

Here’s a full breakdown of how much caffeine you’ll find in your favorite drinks—as well as some of their other pros and cons—so you can choose what to put in your cup wisely. 

1. Brewed Coffee

Caffeine content: 100 to 180 milligrams per eight-ounce serving

Pros: “Brewed coffee contains antioxidants, B vitamins, and minerals, and has been shown to help boost metabolic rate and potentially decrease risk of various diseases,” Blakely notes.

Cons: Because of the wide variety of brews out there, you might not always know exactly how much caffeine you’re getting when you order a cup of coffee. Generally, though, lighter roasts contain more caffeine, according to Blakely. While eight ounces of Starbucks Dark Roast contains 130 milligrams, for example, their Blonde Light Roast packs 180.

2. Green Tea

Caffeine content: 30 to 50 milligrams per eight-ounce serving

Pros: Green tea contains less caffeine than coffee but still provides an energy and cognitive boost, says Blakely. “Green tea also naturally contains an amino acid called l-theanine, which has a calming effect. It works synergistically with the caffeine to promote stable, jitter-free energy,” she explains. “Green tea is also very high in antioxidants, including EGCG.”

Cons: There are not many downsides to green tea—however, it can significantly reduce iron absorption, according to Blakely. “If you have low iron, drink your tea a couple hours apart from eating high-iron foods or taking supplements.”

3. Black Tea

Caffeine content: 50 milligrams per eight-ounce serving

Pros: “Black tea has antioxidants and flavonoids that may protect the body from changes that lead to disease,” says Schnell. “Since black tea goes through an oxidation process, it has different nutritional benefits than green tea.” Studies show that black tea supports heart, gut, and immune health.

Cons: When in iced tea form, some black teas may be sweetened and contain sugar. And, although black tea contains less caffeine than coffee, some people may experience negative side effects if they drink too much, Schnell says. It’s also more likely to have addictive potential.

4. Espresso 

Caffeine: 64 milligrams per one-ounce shot

Pros: Espresso offers similar benefits to regular brewed coffee (more on those shortly) but with a fraction of the caffeine, making it a more suitable option for sensitive sippers.

Cons: Since espresso is often incorporated into lattes and other blended drinks, be wary of how much extra calories, sugar, and fat you’re downing along with that shot, Schnell notes.

5. Decaf Coffee

Caffeine content: 1-7 milligrams per eight-ounce serving

Pros: Decaf coffee allows you to enjoy the taste and nutritional benefits (like antioxidants) of coffee without the jitters, says Blakely. “For those who are sensitive, even a couple milligrams may give them the tiny cognitive boost they’re looking for,” she adds.

Cons: “Like regular coffee, decaf is still highly acidic, which may bother some people’s digestive tract,” says Blakely.

6. Mushroom Coffee 

Caffeine: 50 to 120 milligrams per serving

Pros: Whether in canned, bottled, or drink mix form, mushroom coffees combine coffee with functional mushrooms such as lion’s mane and chaga in order to create an energizing beverage that contains less caffeine than your typical cup of java. “Functional mushrooms support focus, immunity, gut health, and a healthy stress response,” says Schnell. “Mushroom coffee has a great taste (no, it doesn’t taste like mushrooms) and is also rich in antioxidants.”

Cons: Mushroom coffee’s lower caffeine content may be a con for those who are more tolerant. Also noteworthy? These trendy beverages trend to have a higher price point than regular coffee, Schnell notes. 

7. Matcha

Caffeine content: 280 milligrams per four teaspoons

Pros: “Matcha contains antioxidants and catechins (including EGCG), which help support a healthy inflammation response and metabolism, heart health, and energy and alertness,” says Schnell. Like regular green tea, matcha (which is made by grinding high-quality green tea leaves into a powder) also contains l-theanine to balance out its caffeine.

Cons: “Matcha may contain pesticides and contaminants, so it helps to look for an organic option,” notes Schnell.

8. Energy Drinks 

Caffeine content: 70 to 300 milligrams per serving

Pros: “Energy drinks can contain herbs, vitamins, and minerals that support energy and have other health benefits,” says Schnell. “Many people use them to support energy and athletic performance.”

Cons: The amount of caffeine added to energy drinks can vary greatly—and the label doesn’t always indicate just how much you’re getting, Schnell notes. This may increase the likelihood that you end up consuming more than you can tolerate without experiencing side effects.

9. Pre-Workout Drinks And Drink Mixes

Caffeine content: 150-300 milligrams per serving

Pros: “Caffeine can have benefits for physical performance and focus during workouts,” says Blakely. In many cases, pre-workout formulas combine it with other helpful nutrients like electrolytes, amino acids, and antioxidants so they can best support your training.

Cons: Certain pre-workout drinks and mixes contain really high amounts of caffeine, which may not be suitable for more sensitive drinkers or those who exercise in the evening.