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So you’ve decided to improve your health with the help of supplements.
Smart choice my friend.
But with so many different supplements, which ones should you take?
Well, that’s exactly why I created my Supplement Comparison Series to help you decide in a scenario like this.
Next up, we have L-Theanine vs Caffeine.
Ready?
Let’s get started.
What is L-Theanine?

L-Theanine is a popular amino acid known for its calming properties.
Due to its high content in tea leaves, tea is the most common source of L-Theanine for most people.
L-Theanine is one of my favorite amino acids as it’s safe, effective, and good for you.
What is Caffeine?

Caffeine (trimethylxanthine) is arguably the most popular drug in the world.
It’s a stimulant (meaning it stimulates the nervous system) that’s naturally found in beans, fruits, and leaves of over 60 plants worldwide.
The most common source is coffee, and interestingly, Caffeine’s name is derived from the word kaffee, meaning coffee in German.
Benefits
Benefits of L-Theanine
L-Theanine may boost mental performance
According to research, L-Theanine may help enhance mental performance.
It seems to work by amplifying your slow brain waves, which boosts creativity. (Source)
L-Theanine may help combat caffeine jitters
You really can’t beat that first gulp of coffee in the morning.
You know. The one that puts a grin on your face even if it’s a Monday.
But every now and then, the following caffeine rush is unbearable.
I don’t know about you, but it can make me feel anxious, irritable, and jittery.
But since adding some L-Theanine powder to my morning coffee, these effects are barely noticeable.
L-Theanine may help improve sleep
Over the last year or so, I’ve experimented with a few different supplements to help improve my sleep, including:
- Holy Basil
- L-Theanine
- Phosphatidylserine
- California Poppy Extract
My sleep was awesome when taking either Holy Basil alongside Phosphatidylserine, or L-Theanine on its own.
(California Poppy Extract didn’t really do much for me.)
I measure my sleep quality on how long it takes me to fall asleep, and how deep my sleep is.
L-Theanine improve both these factors for me.
Benefits of Caffeine
Caffeine may boost mood and mental performance
Like L-Theanine, Caffeine may boost mental performance.
One study found that Caffeine improved attention, reaction time, and awareness when compared to a placebo.
Also, a review of 12 studies concluded that Caffeine consumers have a 16% lower risk of depression.
Caffeine may enhance exercise performance
According to research, Caffeine may enhance exercise performance.
One study showed that taking 5mg of Caffeine per kilo of body weight an hour before exercise improved endurance by 5%.
Another study found that Caffeine reduced perceived exertion by 5.6%, which may make your workouts feel easier.
Caffeine may help with weight loss
Many popular fat burners and toning supplements list Caffeine as a main ingredient.
And for a pretty good reason too.
One study found that taking 300mg of daily Caffeine can increase calorie burning by 79 calories per day.
Another study of 8 young men found that taking 10mg of Caffeine per kilo of body weight increased fat burning by 13%.
Caffeine may help reduce the risk of Diabetes
Type 2 Diabetes is a nasty disease that’s characterized by high-blood sugar levels.
It can cause some unwelcome symptoms like fatigue, sight loss, excessive thirst, and numb hands and feet.
The positive news is that Caffeine may help protect against Type 2 Diabetes.
A summary of 6 studies concluded that those who consume the most Caffeine have up to a 30% lower risk of developing Diabetes.
Cost
L-Theanine Cost
L-Theanine is generally sold as a powder or in capsules.
Standard prices for these are:
- Powder: $10 for 100g
- Capsules: $20 for 100
Caffeine Cost
Caffeine is usually sold in capsules or tablets.
Here are some typical prices for these:
- Tablets: $7 for 100
- Capsules: $7 for 100
Side Effects
L-Theanine Side Effects
Most people can take L-Theanine supplements with little trouble.
But those who drink tea to get their L-Theanine may notice the following effects if drinking large amounts:
- Nausea
- Irritability
- Stomach upset
Caffeine Side Effects
Like L-Theanine, most people who take Caffeine supplements experience minimal side effects.
But when taken in large amounts, some people may experience:
- Anxiety
- Insomnia
- Headaches
- Rapid heartbeat
Recommendations
My L-Theanine Recommendation: Nootropic Depot L-Theanine Powder
Overview
A long-lasting powdered L-Theanine supplement.
Perfect for those who like the freedom to choose how much L-Theanine they want to take.
What I like about it
I usually prefer supplements that are pure and powdered. Because these are the “cleanest” and you can easily chop and change the dose.
Nootropics Depot L-Theanine Powder ticks both these boxes.
And with each providing a whopping 2500 servings, you only need to buy this once to enjoy some of the best L-Theanine for years to come.
Potential Drawbacks
While I’m a powder fan, some people prefer capsules as you don’t have to taste the supplement.
If that’s you, then you may want to look elsewhere.
Check price and read more reviews of Nootropics Depot L-Theanine on Amazon.
My Caffeine Recommendation: NutraBio 100% Pure Caffeine
Overview
A clean and potent Caffeine supplement in capsule form.
NutraBio 100% Pure Caffeine is the bee’s knees.
What I like about it
An awesome feature of this supplement is the fact that it’s pure Caffeine even though it’s in capsules.
That’s right – no fillers, binders, or any of that other rubbish.
Just 100% pure Caffeine.
Also, the Caffeine used in these capsules is HPLC lab tested by a 3rd party.
This just means the Caffeine is tested to the highest of standards, so I’ll be impressed if you find a better Caffeine supplement that this.
Potential Drawbacks
Some people have experienced an upset stomach after taking these capsules.
Check price and read more reviews of NutraBio 100% Pure Caffeine on Amazon.
L-Theanine vs Caffeine: The Verdict
Thanks for staying with me to the end of this L-Theanine vs Caffeine face off.
I hope it’s been an enjoyable read and you’ve learned something new.
By now, most of you should know exactly which one you’re going to use and have awesome results with.
But if you’re still on the fence, then here’s what I’d go with:
You might prefer L-Theanine if:
- You want to improve your sleep
- You’re a coffee lover but hate the caffeine rush
You might prefer Caffeine if:
- You want to burn more fat
- You to boost your exercise performance
- You want to lower your risk of Type 2 Diabetes
Thanks again, and I’ll see you in the next one.
Robb
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