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Nutrition Reviews

Head to head · Amino Acids (BCAA & EAA)

Kion Aminos Essential Amino Acids Powder vs NOW Foods NAC 600 mg Capsules with Selenium

NOW Foods scores higher overall (7.0 vs 6.3 out of 10), mainly on value, experience and transparency. Kion still leads on efficacy.

Updated October 2026 from our full reviews · How we score

Front of the Kion Aminos Mixed Berry powder tub, 7.0 oz
KionAminos Essential Amino Acids Powder
6.3
Poor

A fully disclosed EAA powder with 5 g of all nine essential amino acids and 2 g of leucine per scoop, sweetened with stevia, at about $1.67 a serving.

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Higher score
Front of the NOW NAC 600 mg bottle, 100 capsules, with selenium
NOW FoodsNAC 600 mg Capsules with Selenium
7.0
Mixed

600 mg of NAC plus 25 mcg of selenium per capsule for about $0.44 a day; well made and plainly labeled, but NAC's benefits for healthy adults are modest.

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We may earn a commission when you buy through these links — it never affects our scores. How we make money

The short answer

Choose Kion if…

  • Older adults and dieters who struggle to eat enough protein
  • People who want a fully disclosed, caffeine-free amino drink between meals
  • Vegans looking for a leucine-rich essential amino acid supplement
  • You care most about efficacy

Choose NOW Foods if…

  • Adults who want a plain, fully disclosed NAC at the commonly studied 1,200 mg daily dose
  • Budget-minded shoppers comparing NAC brands
  • People who prefer NAC from a manufacturer with accredited in-house labs
  • You care most about value, experience, transparency
  • You want the lower cost per serving ($0.22)

Key differences

Biggest scoring gap
Value: NOW Foods 7.6, Kion 4.6. This factor covers cost per effective serving compared with category peers.
Price
NOW Foods costs $0.22 a serving, 87% less than Kion ($1.67): about $6.60 versus $50.10 for 30 servings at the list prices in our reviews.
Independent testing
Neither carries an independent certification we could verify, such as NSF, USP or Informed Choice.
Formula
Of the key ingredients in our reviews, only Kion lists leucine.
Format
Kion: powder, 30 servings per container; NOW Foods: capsule, 100 servings per container.
Dietary labels
Only Kion is labeled vegan and sugar-free. Only NOW Foods is labeled dairy-free and soy-free.

Side by side

Aminos Essential Amino Acids PowderNAC 600 mg Capsules with Selenium
Our score6.3 / 107.0 / 10
Efficacy (30%)6.45.8
Quality & Purity (25%)7.27.5
Value (20%)4.67.6
Experience (15%)6.47.4
Transparency (10%)7.28.0
FormPowderCapsule
Serving1 Scoop (6.60g)30 servings per container1 Capsule100 servings per container
Price per serving$1.67$0.22
Testing & certifications
Third-party testedcGMP facility
cGMP facilityKosherHalal
DietaryVegan, Non-GMO, Gluten-free, Sugar-freeGluten-free, Dairy-free, Soy-free, Non-GMO
Key ingredients
  • L-Leucine2,000 mg
  • L-Lysine HCl, L-Isoleucine, L-Valine, L-Threonine850 / 550 / 500 / 475 mg
  • L-Phenylalanine and L-Methionine350 / 200 mg
  • L-Histidine and L-Tryptophan71.5 mg / 3.5 mg
  • Stevia leaf and monk fruit extracts
  • N-Acetyl Cysteine (NAC)600 mg
  • Selenium (as L-selenomethionine)25 mcg (45% DV)
Flavors4 (Mixed Berry, Cool Lime, Mango…)—
Creator video reviews53

Pros and cons

Aminos Essential Amino Acids Powder

  • Every amino acid dose is disclosed, including 2,000 mg of leucine per scoop
  • No sugar, caffeine, artificial sweeteners or artificial colors
  • Leucine-enriched design mirrors mixtures tested in small human trials
  • About $1.67 per 5 g serving, more per gram of essential amino acids than whey
  • No named third-party certification for drug-tested athletes
All 8 pros and cons

NAC 600 mg Capsules with Selenium

  • 600 mg of NAC per capsule, matching doses used in research when taken twice daily
  • Simple, fully disclosed label: NAC plus 25 mcg of selenium and no proprietary blend
  • NOW tests products in ISO 17025-accredited in-house labs and holds third-party GMP certification
  • Evidence for noticeable benefits in healthy adults is limited
  • Sulfur smell and capsule speckling are common, and some users report stomach upset
All 8 pros and cons

Our verdict: Kion vs NOW Foods

NOW Foods is the stronger product overall, 7.0 to 6.3 in our scoring, ahead on value, experience and transparency. It is also 87% cheaper per serving. Each full review shows the evidence, testing and buyer feedback behind these scores.

Full Aminos Essential Amino Acids Powder review Full NAC 600 mg Capsules with Selenium review

What creators say

Questions people ask

Is Kion better than NOW Foods?
In our scoring, NOW Foods NAC 600 mg Capsules with Selenium rates higher overall (7.0 vs 6.3 out of 10). Kion leads on efficacy; NOW Foods leads on value, experience and transparency. Scores weigh efficacy, quality, value, experience and transparency.
Which is cheaper per serving, Kion or NOW Foods?
NOW Foods costs about $0.22 per serving versus $1.67 for Kion, based on the list prices shown in our reviews. Prices change often, so check the current price before buying.
Who should choose Kion over NOW Foods?
Our reviews suggest Kion is best for older adults and dieters who struggle to eat enough protein, people who want a fully disclosed, caffeine-free amino drink between meals and vegans looking for a leucine-rich essential amino acid supplement, while NOW Foods is best for adults who want a plain, fully disclosed NAC at the commonly studied 1,200 mg daily dose, budget-minded shoppers comparing NAC brands and people who prefer NAC from a manufacturer with accredited in-house labs.
What is the difference between Kion and NOW Foods?
NOW Foods costs $0.22 a serving, 87% less than Kion ($1.67): about $6.60 versus $50.10 for 30 servings at the list prices in our reviews. Neither carries an independent certification we could verify, such as NSF, USP or Informed Choice. Of the key ingredients in our reviews, only Kion lists leucine.

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