Below is a list of questions answering almost everything you wanted to know about Caffeine, sources of Caffeine, and Caffeine Content

Where do coffee beans come from?
Coffee beans come from a Coffee Plant. Coffee Plants can grow in almost type of soil as long as it is given plenty of water and sunshine. The coffee plant requires temperatures ranging between 65 to 75 degrees fahrenheit (minimum). A typical coffee plant will start producing fruit in about 5 years. It is thought to have originated in Ethiopia and is now also grown in Arabia, India, Africa, the West Indies, South and Central America, and on the islands of Java and Sumatra.

What do coffee plants look like?
It's more like a shrub. Below is what a typical one looks like when the fruit is ripe. A typical coffee shrub can grow to heights reaching 40 feet. But they are typically pruned because their maximum yield seems to be at 6 feet and plus it is easier to pick the fruit from a 6 foot shrub rather than a 40 foot one.

Image below is of a coffee plant with unripened coffee beans.
Coffee Plant With Unripened Fruit
Image below is of a coffee plant with ripe coffee beans.
Coffee Plant With Ripe Fruit

How are coffee beans processed?

Coffee bean processing is a multi-step process involving the following:

  1. The fruit from the coffee plant is harvested either mechanically or by hand. It is best to harvest when the fruit is ripe (i.e., red in color).
  2. The harvested fruit is sorted. Since some of the fruit will not be ripe or even damaged, they are sorted out.
  3. The pulp is removed (or mostly removed), leaving behind just the coffee bean. There are a couple of ways to remove The pulp:
    • One way is to use a huge machine to thoroughly soak the bean with fresh water. That makes the pulp easier to remove, but requires a lot of water. Even after this process a thin film is left behind on the bean. In order to remove this film, the bean is thoroughly dried so that the film can simply fall off.
    • Another way is to leave the coffee fruit out to dry. This is a very long process as it can take many weeks for the fruit to dry to the proper level.
  4. Once the fruit undergoes one of those two processes, it is hulled. That is, whether there is a thin film on the fruit or the dried out pulp, this hulling process removes that layer so that you are left with the bean and only the bean. This is a machine assisted operation which gently scrubs off the layers from each bean.
  5. Optional: Decaffeination. Remember that coffee beans naturally contain caffeine so an extra step has to be introduced to make decaf coffee. In this step the coffee beans are moistened first to prepare for extraction of caffeine. Then it undergoes a process called super-critical carbon dioxide extraction or they add ethyl acetate. This process extracts the caffeine into the water which is later drained away.
  6. The coffee is roasted. This step enhances the flavor and smell of the coffee. If you've seen the Folgers commercial where the guy wakes up in the morning, opens up the can of coffee, and takes in the smell of coffee with a huge smile then you know it has been roasted.

Where do tea leaves come from?
Tea leaves come from the Tea Plant. The Tea Plant can be grown in either a tropical or sub tropical area given that it gets at least 127 cm of rainfall per year. It is believed that the best teas are grown at high elevations such as in India and China. The technical name for the tea plant is Camellia Sinensis and there are two main types: The big leaf which is commonly found in India and the small leaf which is commonly found in China.

What do tea leaves look like?
The picture below is of the typical Chinese tea plant.
Chinese Tea Plant

The picture below is of the typical Indian tea plant.
Indian Tea Plant

What is the difference between herbal tea and tea?
Herbal tea is not made from the tea bush at all. So they are technically not a tea. But because they are processed similarily to tea and served just like tea, they are called a type of tea. Herbal teas come from herbs like mint and chamomile and they generally do not contain any caffeine.

What is caffeine?
The scientific name for Caffeine is 1,3,7-trimethylxanthine and it is a naturally occuring drug found in nature (such as coffee beans, tea leaves, and even chocolate). It is labeled as a drug because it fits the literal definition of a drug (i.e., A chemical substance that affects the central nervous system, causing changes in behavior and often addiction). If you've often said to yourself that you can't function properly in the morning without your cup of coffee, then you are most likely addicted to caffeine.

The chemical composition of Caffeine is illustrated below
Chemical Structure of Caffeine

How much caffeine is too much?
According to the Mayo Clinic, you should restrict your daily intake of caffeine to less than 500mg. Any more, then you risk developing some bad health side effects from caffeine. See the FAQ below for a list of those effects.

What is the caffeine content for a cup of coffee?

All amounts are based on 8oz cup size unless stated otherwise.

Type Amount (mg)
Generic Brewed Coffee 95-200
Generic Brewed Decaffeinated 2-12
Generic Instant 27-173
Generic Instant Decaffeinated 2-12
Starbucks Espresso, 1 oz 58-75
Starbucks Vanilla Latte, 16 oz 150

What is the caffeine content for a cup of tea?
The amounts below are based on an 8oz cup unless stated otherwise.

Type Amount (mg)
Black Tea 64
Oolong Tea 48
Green Tea 32
White Tea 24
Starbucks Tazo Chai Tea Latte, 16 oz 100
Rooibos Tea 0
Olive Leaf Tea 0

Does decaf coffee have caffeine?
Yes it does. See the table above. Also read the question on processing coffee to understand why decaf coffee has Caffeine.

What are the common side effects of Caffeine?

What other products contain caffeine?
You would be surprised how many products contain caffeine. See the list below to get a better picture of just how much caffeine you are taking in on a daily basis. Note that these are approximate amounts.

Type Amount (mg)
7Up, regular or diet 0
Barq's Root Beer, regular or diet 23
Coca-Cola Cherry, regular or diet 34
Coca-Cola Classic 34
Coca-Cola Zero 34
Diet Coke and Diet Coke With Lime 47
Dr Pepper, regular or diet 42-44
Fanta, all flavors 0
Mello Yello 53
Mountain Dew, regular or diet 54
Mountain Dew Code Red, regular or diet 54
Mug Root Beer, regular or diet 0
Pepsi, regular or diet 36-38
Sprite, regular or diet 0
TaB 47
Vault 71
Wild Cherry Pepsi, regular or diet 38
AMP, 8.4 oz 74
Enviga, 12 oz 100
Full Throttle, 16 oz 144
Monster Energy, 16 oz 160
No Fear, 8 oz 83
Red Bull, 8.3 oz 76
Rockstar, 8 oz 80
Foosh Energy Mints, 1 mint 100
Hershey's Milk Chocolate bar, 1.55 oz 9
Hershey's Special Dark Chocolate bar, 1.45 oz 31
Jolt Caffeine-Energy Gum, 1 stick 33
Ben and Jerry's Coffee Heath Bar Crunch, 8 oz 84
Haagen-Dazs Coffee ice cream, 8 oz 58
Starbucks Coffee ice cream, 8 oz 50-60
Anacin, Maximum Strength, 2 tablets 64
Excedrin, Extra Strength, 2 tablets 130
NoDoz, Maximum Strength, 1 tablet 200