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NOW L-Theanine 100 mg vs Optimum Nutrition Essential Amino Energy

The published reviews of NOW L-Theanine 100 mg and Optimum Nutrition Essential Amino Energy, lined up: the five scores, what one serving delivers against the studied dose, the real cost per serving and what each label leaves out. Figures as of 28 September 2026.

The short answer

NOW L-Theanine 100 mg scores 6.4/10 against Optimum Nutrition Essential Amino Energy's 5.4. The widest gap is label transparency: 9 for NOW L-Theanine 100 mg, 5 for Optimum Nutrition Essential Amino Energy.

Pick NOW L-Theanine 100 mg if…

  • you want every amount on the label disclosed
  • you want better value against the plain generic version
  • you want a serving that matches the amount used in research

Pick Optimum Nutrition Essential Amino Energy if…

  • tolerability and a well-characterised safety record come first
  • you want the stronger evidence behind what it is sold to do

Criterion by criterion

The five criteria every review is scored on, published on the grading page. The overall score is their average.

Evidence for the marketed claim

How strong the research is for what the product is actually sold to do — not for the ingredient in general.

NOW L-Theanine 100 mg5/10
Optimum Nutrition Essential Amino Energy6/10Leads

Dose against the studied amount

Whether one serving delivers the amount used in the research behind the claim.

NOW L-Theanine 100 mg6/10Leads
Optimum Nutrition Essential Amino Energy5/10

Label transparency

Whether the Supplement Facts panel is published in readable text and every active amount is disclosed.

NOW L-Theanine 100 mg9/10Leads
Optimum Nutrition Essential Amino Energy5/10

Value against the generic equivalent

Cost per gram or per dose of the active ingredient, compared with the plainest version of the same thing.

NOW L-Theanine 100 mg6/10Leads
Optimum Nutrition Essential Amino Energy3/10

Safety and tolerability

Known risks and interactions, how well characterised they are, and whether the label warns about them.

NOW L-Theanine 100 mg6/10
Optimum Nutrition Essential Amino Energy8/10Leads

Dose against the studied amount

What one labelled serving delivers, placed against the range on each ingredient’s evidence page. Where a label gives no figure, there is nothing to place, and that is the finding.

Green tea extractEvidence C

No single studied range in label units, so amounts are shown but not placed.

  • NOW L-Theanine 100 mg250 mg per capsule (500 mg at the label’s upper dose)
  • Optimum Nutrition Essential Amino Energy100 mg per serving

L-theanineEvidence B

Studied dose: 100–200 mg a dose

  • NOW L-Theanine 100 mg100 mg per capsule (200 mg at the label’s upper dose)In range
  • Optimum Nutrition Essential Amino EnergyNot in the formula

What it actually costs

Price divided by labelled servings, from a dated listing. A serving is whatever the label calls one, which is why the studied-dose row matters more than the headline figure.

  • NOW L-Theanine 100 mg$0.24 a serving · $21.99 for 90 servings at NOW Foods, checked 22 Sept 2026
  • Optimum Nutrition Essential Amino EnergyAbout £19.75–£26.83 for the 270 g tub at mainstream UK retailers in search listings on 28 September 2026 — roughly 66p–89p a serving. No per-serving figure: servings not recorded.

Label checks

What each label discloses, and what it leaves out. Read from the reviews, not from the marketing.

NOW L-Theanine 100 mg

  • Every active ingredient has a stated amount
  • No third-party certification

Optimum Nutrition Essential Amino Energy

  • Every active ingredient has a stated amount
  • No third-party certification

How this comparison is built

  • Scores are the ones already published in each review. Nothing is re-scored for the comparison, and a product leads a criterion only when it outscores the rest.
  • Doses are read from the label rows in each review and placed against the studied range on the matching ingredient page. A figure that is not printed is never estimated.
  • Costs use a dated retailer price divided by labelled servings. Prices in different currencies are never ranked against each other.
  • Only products in the same category, or ones a review names as an alternative, can be compared. Commission never changes what appears here.

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