Customer Ratings & Reviews

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4.8

Based on 680 ratings

597

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What customers say

(317)

iHerb Customer

Posted on 10/06/2026

United Kingdom

Great product Value and quality

Verified Purchase

Amazing product, very high purity and effective and helps with energy!

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mohammd

Gold

Posted on 9/06/2026

Saudi Arabia

780

313

1,422

Beautiful and wonderful

Verified Purchase

The quality is good. It's worth noting that while it's a lab-made product, it's the same caffeine molecule as regular coffee. Whether the plant synthesizes it within the coffee bean using its own enzymes, or a chemist synthesizes it in a test tube in a lab, the end result is a 100% geometric and atomic match to the exact same molecule. And the coffee itself is surrounded by fibers, essential oils, and antioxidants.

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Antonio-Scalzi-Erborista

Posted on 20/09/2025

Italy

2 capsules of 200 mg caffeine per day to recover all the energy you need

Verified Purchase

I'm a herbalist, nurse assistant, and naturopath. I write when I have scientific evidence, not just personal experience. I have a very physically demanding job: I'm a nurse assistant in the US. Coffee used to be my ally, but it had several physical side effects: cramps, gastritis, etc. With two caffeine capsules a day (1 in the morning, 1 at lunch), I no longer have any problems. Pure caffeine contains neither waxes nor fats, nor caffeic acid: all substances found in coffee that irritate the digestive mucosa. Remember that 400 mg of caffeine corresponds to 5-6 cups of Italian espresso from a café, while with a home moka pot, three cups are enough to exceed 400 mg, so you're not consuming dangerous amounts. Clinical evidence suggests that 400 mg is well tolerated by a healthy body and even helps protect the brain and liver.

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MartinJavier

Posted on 25/08/2026

Mexico

Energy in my workouts!

Verified Purchase

I'm doing an hour at the gym and also walking and jogging 3 to 5 km. I feel very active and energetic with these capsules, I will continue using them!

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iHerbCustomer

Gold

Posted on 9/07/2026

Jordan

476

Verified Purchase

Fuel your day: Nutricost caffeine capsules provide an energy boost to help you stay focused and alert throughout the day. Sugar-free and free of unhealthy additives: Enjoy the benefits of caffeine without the unwanted sugar or other unhealthy additives commonly found in sodas or energy drinks.

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iHerb Customer

Posted on 16/06/2026

Mexico

Excellent quality.

Verified Purchase

High-quality product, the perfect dose ideal for training and your daily routine, full of energy, excellent results, benefits, and efficiency. I highly recommend it as a great package and a delicious product. Good composition and dosage frequency. It also arrived very quickly thanks to the shipping company, and the packaging is excellent; it will last me for several months.

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iHerbCustomer

Silver

Posted on 8/06/2026

Ukraine

181

A great product for increasing concentration and energy

Verified Purchase

A great product for increasing concentration and energy. The capsules are easy to use, the dosage is optimal. Helps you wake up quickly in the morning and work productively throughout the day without sudden energy drops. Excellent value for money.

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iHerbCustomer

Posted on 9/03/2026

Saudi Arabia

Verified Purchase

Caffeine is a stimulant that directly affects the central nervous system, stimulating the brain and increasing alertness. When consumed, caffeine is rapidly absorbed into the bloodstream and reaches the brain, where it counteracts the effects of adenosine, the neurotransmitter responsible for feelings of tiredness and sleepiness.

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Waad

Posted on 3/03/2026

Saudi Arabia

caffeine

Verified Purchase

Honestly, I feel it sometimes wakes me up, but you have to eat something sweet afterward so it doesn't cause tremors or a drop in energy.

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iHerb Customer

Posted on 12/08/2026

Colombia

caffeine real

Verified Purchase

Nutricost is the preferred brand for caffeine capsules before training; it's almost mandatory for anyone who wants to train with good intensity. I use 400 mg before leg training – the capsule form takes longer to take effect compared to tablets.

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