










⚡ Elevate your hustle with calm, clean energy—no jitters, just results!
NATURAL STACKS Smart Caffeine Pills combine 100mg of pure caffeine with 200mg of L-Theanine from green tea to provide a smooth, focused energy boost without jitters or crashes. This vegan, gluten-free, and non-GMO supplement supports sustained mental clarity and productivity, backed by transparent sourcing and third-party testing. Ideal for professionals seeking a reliable coffee alternative to power through demanding days.
















| ASIN | B00GXPNEUO |
| ASIN | B00GXPNEUO |
| Age Range Description | Adult |
| Allergen Information | Gluten Free |
| Best Sellers Rank | #55,394 in Health & Household ( See Top 100 in Health & Household ) #236 in Sports Nutrition Endurance & Energy Supplements #15,636 in Vitamins, Minerals & Supplements |
| Brand Name | NATURAL STACKS |
| Color | Blue |
| Container Type | Bottle |
| Customer Reviews | 4.3 4.3 out of 5 stars (640) |
| Date First Available | November 27, 2013 |
| Diet Type | Gluten Free |
| Dosage Form | 1 Capsule |
| Flavor | Unflavored |
| Is Discontinued By Manufacturer | No |
| Item Dimensions | 3.94 x 3.94 x 3.94 inches |
| Item Form | Capsule |
| Manufacturer | Natural Stacks |
| Manufacturer | Natural Stacks |
| Manufacturer Part Number | PB-Q91J-HSEU |
| Material Features | Vegan |
| Number of Items | 1 |
| Primary Supplement Type | Caffeine |
| Product Benefits | Focused Energy |
| Product Dimensions | 3.94 x 3.94 x 3.94 inches; 1.76 ounces |
| Special Ingredients | Caffeine, L-Theanine |
| Specific Uses For Product | Energy, Focus |
| UPC | 798295452535 |
| Unit Count | 60 Count |
T**W
An Energy Boost Just When You Need It!
Are you exhausted and mentally plus physically worn out? Life can do that to you and sometimes you need a little boost of caffeine energy to get through another day. I was feeling emotionally worn out from dealing with a situation that was not resolving itself and I was having low motivation to get things done. Then I remembered I had these capsules and figured one couldn't hurt. I will say these do give you an energy that is more long lasting and it didn't make me feel anxious or wired and I felt no crash besides that I ended up going to bed a little earlier that night. I'd say from the time I took one capsule to the moment I got active was about 20 minutes. I cleaned my whole kitchen, did several loads of laundry and did other things around the house that needed to be done. I literally felt like all the negative emotions I'd been feeling dissolved into a sense of happiness and peace. I will however say that you don't want to take these if you are not near a restroom because I found out these have a diuretic effect like coffee. Make sure to drink plenty of water even if you only take one capsule. I am not a doctor, nor is this medical advice. Some people also can't handle much caffeine due to heart or anxiety issues. So use with caution. But overall I felt these were safe enough for me and did give me more energy than a cup of coffee. I personally would not take more than one capsule at a time during a day and would not take these every single day. I consider these more a last resort when I'm really low on energy or feeling emotionally drained. For that they work like a miracle! ~The Rebecca Review
S**.
Convenient powder pill, add to yogurt and your stomach will thank you for quitting coffee.
How did I live without this product?
D**H
Great Variant for a "Grown Up" Energy Supplement!
A school teacher who is a drama director. I don't use this a lot, but when needed for those longer afternoons rehearsing at the theatre. If I take 1 Smart Caffeine at lunch time, I coast energetically through the rest of the day without feeling caffeine jitters. I prefer taking it with my lunch around 12:30, but if I forget, and take 1 later, if I have 1 tablet no later than 2:00 PM, it's still effective, and does not have a linger after effect, when I go to bed. It doesn't effect my somewhat fragile sleeping pattern.
B**E
Works great, but a little pricey
Lost one star because of the price. This stuff works great, but it's FAR more cost effective to just buy l-theanine separate in powder form and take it with coffee or a generic brand caffeine pill (you can get 120 caffeine pills for 6 bucks with 100mg of caffeine a pill, and 100 GRAMS of l-theanine powder for 22 bucks - that's (500) 200mg doses worth of l-theanine). If you really wanted to go all out, you could buy a pill machine and empty vegcaps and make them yourself - still cheaper. This is definitely a great and effective product, but the cost of the convenience of having them pre-mixed together in a vegcap is far too much in this case.
C**M
May cause drowsiness.
You should know that this can have the reverse effect and make you sleepy. Took me a week to figure out why I could hardly.function after starting this supplement. No jittery feelings, but several naps. So a no-go for me.
B**.
Great Product
Currently trudging my way through grad school while working, and often find myself with low energy and unable to focus. Must be the lack of sleep huh? Wrong. Despite being extremely busy, I usually average about 6-8 hours of sleep per night, the exact same amount I had before I went back to grad school. Because of this, I figured I would get something relatively natural and low impact to help increase my energy and focus. I opted for this particular brand because the reviews were pretty good, the packaging and marketing looked rather legit ( I know this may seem like a crazy thing to go off of, but with vitamins if they look like they belong in an infomercial, I feel nervous.) and the price was right. I got them in the mail, and within a week I noticed that I had increased energy, and after two weeks I saw that it was even more intensified. With that said, I still hadn’t seen any improvement in focus, so I decided to “stack” (new supplement lingo I learned from a guy at a health foods store) another supplement, called NootropX - 90 caps - Mental Focus and Concentration Supplement With Memory Enhancement For Extreme Clarity and Alertness - Instant Brain and Memory Power Boost From Patented AES® Absorption System - The Ultimate Brain Vitamins which is a little bit more geared towards the focus aspect I was looking for. After two weeks of taking both of those, I noticed that I was performing better at school and work, and I had the energy to do even more than I had hoped for. My work was coming out better, as I had been able to focus more. I definitely recommend this supplement to anyone who is looking for an energy boost, and even though it didn’t give me a boost in focus, it’s still a great product and since everyone’s body is different it may work for you!
S**I
No jitters packed with energy
This is has made a huge difference in my daily life. Definitely has increased my energy without feeling shaky.. I would recommend this ; just be aware not to take it in afternoon. It will def affect your sleep; stop taking at least 5 hours before bed
L**)
Not what it claims
Did not work for me. Made me tired, super irritable and everything was in a weird slow motion for several hours. I didn't get any caffeine feel whatsoever. It was the complete opposite. The item says it's returnable, but when I tried to return it it said it was ineligible for a return. What a waste of $20 bucks.
M**S
Excellent source of energy and calm. I don't tend to use it everyday or even at the full recommended usage. But I really think this nootropic stack has helped me considerably during some of the more busy or challenging times of my life.
A**R
Good product,, I like it
C**N
Does what it says on the tin. Good, focused energy. Very useful for those days you need a boost to your productivity and be more on task!
B**S
Really helps me stay productive throughout the day without having to guzzle endless cups of coffee. No jitters, just clarity and focus all the way.
D**L
It's a good product overall, it really takes my concentration up a notch and also alleviates my tiredness from not sleeping a lot. My wife though did not notice anything at all, so I'm guessing it doesn't affect everyone equally. Also the product comes well protected and the delivery was on time for me. The package it came in was not so good in my opinion, because it came on a card like box, which anyone could put a hand inside and take it, don't know if this is because of security borders so they can check is not drugs, but non the less wanted to leave that remark. Thank you!
Trustpilot
1 day ago
2 weeks ago