Our Verdict
SiS GO Electrolyte is a performance-focused isotonic drink designed for endurance athletes, not a clean electrolyte supplement. With 36g carbs and only 200mg sodium per 40g serving, it's primarily a carbohydrate fuel source with modest electrolytes. The Informed Sport certification (100% batch testing) is its strongest quality signal. The presence of aspartame and maltodextrin makes it unsuitable for clean-label-focused consumers.
Evident Ratings
Science in Sport (SiS) SiS GO Electrolyte Powder
Scored across 5 dimensions on a 5-point scale
About Science in Sport (SiS)
Science in Sport (SiS) was founded in 1992 in the UK and is one of the world's largest endurance sports nutrition brands. The company is publicly traded on the London Stock Exchange and supplies numerous professional cycling and running teams.
Product specifications
- Form
- powder
- Serving Size
- 2 scoops (40g) in 500mL water
- Calories
- 146
- Sugar
- 6.7g
- Made In
- UK
How we scored this
Every data point below is tagged as Verified (independently confirmed) or Claimed (brand-stated).
Material Safety
- No Artificial Sweeteners
- No — Contains Aspartame, an artificial sweetenerVerified
- No Artificial Flavors
- Yes — Uses natural flavouringVerified
- No Artificial Colors
- YesVerified
- No Natural Flavors
- No — Contains 'Natural Flavouring'Verified
- No Fillers
- No — Maltodextrin is 92% of the formula (though serving a functional purpose as carb fuel)Verified
- Transparent Label
- Yes — Full nutritional breakdown providedVerified
- No Proprietary Blends
- YesVerified
- Clean Mineral Sources
- Yes — Uses lactate and citrate formsVerified
- Sweetener
- Aspartame (contains Phenylalanine)Verified
- Full Ingredients
- Carbohydrate Mix (93%) (Maltodextrin produced from partial hydrolysis of a special variety of Maize, Fructose), Citric Acid, Electrolytes (2%) (Sodium Chloride, Calcium Lactate, Potassium Chloride, Sodium Citrate, Magnesium Citrate), Natural Flavouring, Sweetener (Aspartame). Contains a source of Phenylalanine.Verified
Testing & Trust
- Third-Party Tested
- Yes — Informed Sport certified, 100% batch testingVerified
- COA Available
- Unknown
- Heavy Metals Tested
- Unknown
- Certifications
- informed sport, gmp certified, vegan, gluten freeVerified
Value & Policy
- Price Per Serving
- $0.87Verified
- Package Price
- $34.99 (40 servings)Verified
Product Features
- Sodium
- 200mgVerified
- Potassium
- 60mgVerified
- Magnesium
- 5mgVerified
- Calcium
- 27mgVerified
- Sodium Source
- Sodium Chloride, Sodium CitrateVerified
- Magnesium Source
- Magnesium Citrate (previously listed as Magnesium Lactate)Verified
- Amazon Rating
- 4.4 stars (5,000 reviews)Verified
- Red Flags
- Contains aspartame (artificial sweetener); Very high carb content (36g per serving); Low actual electrolyte content relative to serving sizeVerified
See how Science in Sport (SiS) stacks up against every electrolytes we tested
Our full electrolytes comparison ranks every brand across the same scoring dimensions you saw above — formulation, testing, trust, value, and sourcing.
See Best Electrolytes →Other top electrolytes we tested
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