Nutricost Caffeine with L-Theanine 100 mg / 100 mg Review
#8 of 8 · Best Value 1:1✓ Label verified · Supplement Facts read Sep 20, 2026Real retailer photo, cut out. Label unedited.
Buy it if you want cheap caffeine with some theanine; know it is not the studied ratio. At six cents a capsule with third-party testing this is very good value for caffeine.
$13-15~$0.06 per capsule (100 mg caffeine + 100 mg theanine)
Why It Scores 7.7 — And The Label Line Behind Each Number
Ratio & Dose vs the Trials
30% of score100 mg caffeine to 100 mg L-theanine is a 1:1 ratio, half the theanine the trials paired with caffeine; the weakest trial match on the list.
- Per serving
- 100 mg caffeine anhydrous, 100 mg L-theanine
Ingredient Sourcing & Form
20% of scoreAnhydrous caffeine and unbranded L-theanine in a gelatin capsule with rice flour, microcrystalline cellulose, magnesium stearate and silica.
- Form
- Gelatin capsule
- Other ingredients
- Rice flour, gelatin capsule, microcrystalline cellulose, magnesium stearate (vegetable source), silica
Testing & Manufacturing
20% of scoreThird Party Tested, GMP compliant facility, non-GMO and gluten-free marks in the gallery quality panel.
- Seals
- Non-GMO, gluten-free, third party tested, GMP compliant facility (gallery)
Dosing Flexibility & Practicality
15% of scoreOne 100 mg capsule per dose, 240 per bottle; adding a second capsule doubles the caffeine, not just the theanine.
Value
15% of scoreAbout $0.06 per capsule, the lowest price on the list.
- Serving
- 1 capsule
- Count
- 240 capsules (240 servings)
- Cost per dose
- ~$0.06 per capsule
Label verified. Every figure read from the Supplement Facts photo, Sep 20, 2026.
Marketing Claims Vs. Reality
100 mg of each per serving.
The panel declares 100 mg caffeine anhydrous and 100 mg L-theanine per capsule.
Third party tested.
Third Party Tested and GMP compliant facility appear in the gallery quality seals alongside non-GMO and gluten-free.
The smart caffeine stack.
Caffeine plus theanine is the studied stack, but at 1:1 this product carries half the theanine per milligram of caffeine that the trials used.
What Our Test Actually Found
Right idea, wrong ratio
Every trial that showed the combination beating caffeine alone used more theanine than caffeine, usually twice as much. Nutricost's equal split is a caffeine pill with a theanine garnish, not the studied pairing.
Unbeatable on price
Six cents a capsule with third-party testing is hard to argue with if caffeine is what you are actually buying. Add your own theanine and it becomes a workable 1:2 stack for about twelve cents.
Full analysis: all pros & cons (6), buy if / skip if
- About $0.06 per capsule, 240 per bottle
- Third-party tested and GMP in the gallery
- Simple, quantified formula
- 1:1 ratio, half the studied theanine
- Gelatin capsule, not vegan
- Generic anhydrous caffeine with five excipients
- You want the cheapest caffeine capsule with theanine in it
- You already take extra L-theanine and want to top up caffeine
- You want third-party testing at a budget price
- You want the 1:2 ratio the trials used
- You are vegan; the capsule is gelatin
- You want natural caffeine
At six cents a capsule with third-party testing this is very good value for caffeine. It is not the combination the trials tested: they used twice as much theanine as caffeine, and Nutricost gives you equal amounts. You could add a separate theanine capsule, at which point the price advantage narrows. The gelatin capsule rules out vegans.
Nutricost's combo is the value buy: 240 capsules of 100 mg caffeine anhydrous and 100 mg L-theanine for around $14, with non-GMO, gluten-free, third-party tested and GMP marks in the gallery. The catch is on the panel: 100 mg of theanine to 100 mg of caffeine is a 1:1 ratio, half the theanine the placebo-controlled trials paired with their caffeine, and the capsule is gelatin with rice flour, microcrystalline cellulose, magnesium stearate and silica.
A good caffeine pill that is not quite the combo the trials used
Buy it as cheap, tested caffeine with a little theanine. Do not buy it expecting the smooth-focus effect of the 1:2 products; add a separate 100 mg theanine if you want that.
If This Doesn’t Fit — Try These
01Zhou Energy + Focus
Natural caffeine, the studied ratio, a vegan capsule and almost nothing else.
02Natural Stacks
The same pairing and dose as the winner with the best testing transparency on the list.
03Sports Research
If you want to know exactly which caffeine and which theanine you are taking, this is the only product here that names both.
Quick Answers
Is 100 mg caffeine to 100 mg L-theanine the right ratio?
It is not the ratio the trials used. Owen 2008 and most follow-ups paired about twice as much L-theanine as caffeine. Nutricost gives equal amounts, so the theanine effect is likely weaker per capsule.
Is Nutricost Caffeine with L-Theanine vegan?
No. The capsule is gelatin per the panel.
Sources & Further Reading
2 peer-reviewed sources, each linked to PubMed
- [1] Haskell CF, Kennedy DO, Milne AL, Wesnes KA, Scholey AB. Biol Psychol. 2008;77(2):113-22. PMID 18006208 — The effects of L-theanine, caffeine and their combination on cognition and mood. 150 mg caffeine with 250 mg L-theanine improved speed and accuracy of rapid visual information processing and reduced susceptibility to distraction versus placebo, while theanine alone slowed some reaction times.
- [2] Rogers PJ, Smith JE, Heatherley SV, Pleydell-Pearce CW. Psychopharmacology (Berl). 2008;195(4):569-77. PMID 17891480 — Time for tea: mood, blood pressure and cognitive performance effects of caffeine and theanine administered alone and together. 200 mg L-theanine blunted the blood-pressure rise produced by 250 mg caffeine, while caffeine's alerting effect on cognition was preserved, in a placebo-controlled study.
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