Caffeine in tea vs. coffee

Lots of us rely on caffeine to jumpstart the day, whether it’s from a fresh-brewed coffee or a pot of tea. In the UK alone, nearly 123 million cups of tea and 90 million cups of coffee are consumed every day. Whether you’re team tea or coffee—or both—these popular drinks have caffeine in common, even when labelled as decaf.

Caffeine works by stimulating the central nervous system. Once it reaches your brain, it can leave you feeling more alert—less tired and more ready to take on the day.

What is caffeine?

Caffeine is a stimulant that speeds up communication between the brain and body. It naturally exists in the seeds, nuts, and leaves of certain plants. These include Coffea Arabica (coffee), Thea Sinensis (tea), Cola Acuminata (used in colas and soft drinks), Theobroma Cacao (cocoa and chocolate), and Paullinia Cupana (common in energy drinks and some snack bars).

Is caffeine good for you?

We might crave it, but should we be concerned about our caffeine intake? Research suggests moderate amounts of tea and coffee don’t negatively impact health. In fact, drinking about three to four cups per day is typically considered safe and may even help defend against conditions like heart disease and type 2 diabetes.

Summary

  • Caffeine stimulates communication between the brain and body.
  • Moderate tea and coffee intake is generally safe.
  • Three to four cups daily may offer health benefits.

Reasons to go caffeine-free

Caffeine has its perks, but it isn’t for everyone. Some simply dislike the taste, while others experience unpleasant side effects.

Common side effects include:

  • Restlessness, excitability, or dizziness
  • Anxiety or irritability
  • Increased urination or dehydration

It may also lead to:

  • Elevated body temperature
  • Faster breathing or heart rate
  • Headaches and difficulty focusing
  • Upset stomach

Long-term high intake (over four cups daily) may cause:

  • Sleep disruption
  • Ulcers and digestive issues
  • Osteoporosis risk in postmenopausal women
  • Muscle tremors or fatigue
  • Irregular heart rhythms or dizziness
  • Appetite loss, nausea, or diarrhoea
  • Low blood pressure and fainting

Summary

  • Caffeine can cause discomfort like jitters or dizziness.
  • It may impact digestion, sleep, or hydration.
  • High consumption over time can cause more serious effects.

The caffeine content in a cup of coffee

Caffeine content varies depending on the coffee type and preparation:

  • Brewed coffee (8oz/237ml): 95–200mg
  • Decaf brewed coffee (8oz): 2–12mg
  • Espresso (1oz/30ml): 47–75mg
  • Decaf espresso: 0–15mg
  • Instant coffee (8oz): 27–173mg
  • Decaf instant coffee: 27–173mg
  • Latte (8oz): 63–175mg

Caffeine in a cup of tea

Tea isn’t caffeine-free either, though levels vary by type:

  • Black tea with milk: around 47mg per cup
  • Green tea: averages 33mg per cup
  • Matcha green tea (½ tsp): about 35mg
  • Herbal teas from non-tea plants: caffeine-free
  • Herbal blends with green or black tea: will contain caffeine

Caffeine in coffee vs tea

On average, coffee packs about twice as much caffeine as black tea. A brewed coffee usually has around 95mg per cup, but can vary based on bean type, roast, and brew method. An espresso shot contains roughly 63mg, while instant coffee ranges from about 30 to 90mg.

Summary

  • Brewed coffee (8oz): 95–200mg caffeine
  • Black tea with milk: around 47mg
  • Caffeine levels depend on bean/leaf type and processing

Does decaf coffee contain caffeine?

Yes—just less of it. Regular brewed coffee contains 95–200mg of caffeine per 8oz, while decaffeinated versions hold about 2–15mg. The exact amount depends on the bean, the decaffeination process, and how it’s brewed. There isn’t a set legal caffeine limit for decaf, but per FDA guidelines, at least 97% of original caffeine must be removed for the decaf label to apply.

Does decaf tea contain caffeine?

Just like coffee, decaf tea isn’t totally caffeine-free. Legally, decaf tea must contain less than 2.5% of its original caffeine, which typically means under 2mg per cup.

Other food and drink that contains caffeine

Caffeine isn’t just in tea and coffee. It pops up in many foods and drinks:

  • Regular coffee (black): 95mg
  • Espresso (1 shot): 63mg
  • Instant coffee: 63mg
  • Latte or mocha: 63–126mg
  • Decaf coffee: 2mg
  • Energy drinks: around 91mg
  • Green tea: 28mg
  • Sugar-free soft drinks: 41mg
  • Kombucha: 10–15mg

Some surprising things that contain caffeine

  • Chocolate – Because caffeine naturally exists in cocoa, darker varieties usually contain more.
  • Ice cream or frozen yoghurt – Some brands offer frozen treats with up to 45mg of caffeine.
  • Breakfast cereals – Especially chocolate-flavoured versions may include small amounts.
  • Desserts – Those made with chocolate or cocoa will usually contain caffeine.
  • Hot cocoa – Even this comforting drink has anywhere from 0 to 2mg of caffeine.

Peppermint tea, if made purely from peppermint leaves, is naturally caffeine-free and a great alternative for those cutting back.

Summary

  • Even decaffeinated tea and coffee contain some caffeine.
  • Caffeine also appears in chocolate, fizzy drinks, kombucha, ice cream, cereals, and more.

Is decaf tea and coffee good for you?

Decaf coffee still delivers a useful amount of antioxidants and key nutrients like magnesium, potassium, and B vitamins. It’s been linked to lower type 2 diabetes risk and offers liver protection too. Decaffeinated tea also supplies antioxidants, which can help relieve inflammation and protect cells as we age.

10 caffeine free hot drinks

Thinking about going sans caffeine, or just want to mix in some variety? Here are 10 caffeine-free hot drink ideas:

  1. Chamomile tea
  2. Turmeric milk
  3. Rooibos tea
  4. Mint tea
  5. Barley, rye & chicory cereal drink
  6. Lemon and ginger tea
  7. Nettle tea
  8. Lemon water
  9. Peppermint tea
  10. Rose tea

Summary

  • Decaf versions still offer health benefits thanks to their antioxidants and nutrients.
  • There are plenty of caffeine-free hot drink options out there, from herbal teas to turmeric milk.

To conclude…

This deeper dive into caffeine reveals it’s not just in your morning cup of tea or coffee—it hides in many food and drink items, too. From ice cream to cereals, it turns up in unexpected places. Whether you’re cutting back or just becoming more aware of your intake, understanding caffeine’s effects and where it comes from can help you make better choices daily.

Sources

Disclaimer

The advice in this article is for information only and should not replace medical care. Please consult your GP or healthcare provider before starting any supplements, treatments, or remedies. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle.