Klean Athlete

Klean Casein Protein - Natural Vanilla Custard Flavor, 614 g

Klean Casein Protein is a micellar casein-based protein powder from Klean Athlete, formulated to support muscle protein synthesis and recovery during overnight or extended fasting periods.

May be a fit for

  • Athletes seeking slow-digesting casein protein for overnight muscle recovery
  • Individuals supporting lean muscle retention during extended fasting periods
  • Competitors requiring NSF Certified for Sport casein before bedtime feeding
$68.99

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PowderFormat
614 gPack size
The essentials

A closer look.

Klean Casein Protein is a micellar casein-based protein powder from Klean Athlete, formulated to support muscle protein synthesis and recovery during overnight or extended fasting periods. Designed for competitive and serious athletes, it delivers a slow-digesting protein source that may help maintain muscle mass between training sessions.

Why It's Worth Considering: Klean Athlete holds NSF Certified for Sport® certification, meaning each batch is tested for banned substances, a meaningful distinction for athletes subject to drug testing. The Natural Vanilla Custard flavor uses no artificial sweeteners or colors.

Inside the formula

Product details

Who it may suit

May be a fit for

  • Athletes seeking slow-digesting casein protein for overnight muscle recovery
  • Individuals supporting lean muscle retention during extended fasting periods
  • Competitors requiring NSF Certified for Sport casein before bedtime feeding
  • Those using micellar casein to maintain positive nitrogen balance between meals

Considerations

  • Known allergy to any ingredient (check label)
  • Currently pregnant or breastfeeding (consult healthcare provider)
  • Taking prescription medications (check for interactions)
  • Under 18 years of age (unless recommended by pediatrician)
Compatibility & interactions

Works Well With

Creatine
Both support muscle recovery
B-Complex
B vitamins support protein metabolism

Take Separately From

No significant interactions identified. Always consult your healthcare provider.

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Good to know

A few useful answers.

Research & further reading

More category questions

How should I store this supplement?

Store in a cool, dry place away from direct sunlight. Most supplements are stable at room temperature (59-77°F). Keep the bottle sealed between uses. Check the label for any specific storage requirements — some probiotics and oils require refrigeration.

Can I take this with other supplements?

Most supplements can be taken together safely. However, some minerals compete for absorption (zinc and iron, calcium and magnesium) and should be taken at different times of day. If you're taking prescription medications, consult your healthcare provider about potential interactions.

How long should I take this supplement?

Most supplements benefit from consistent daily use over 2-3 months to achieve full effect. Some (like vitamins and minerals) can be taken indefinitely as part of a daily routine. Others (like specific herbs) may benefit from cycling. Follow the product's recommended protocol or consult a practitioner.

When is the best time to take this?

Fat-soluble supplements (vitamins A, D, E, K, omega-3, CoQ10) should be taken with a meal containing fat. Water-soluble supplements (B vitamins, vitamin C) can be taken anytime. Minerals are generally best absorbed with food. Probiotics should be taken with or just before a meal. Check the product label for specific timing recommendations.

How do I know if this supplement is working?

Track your specific health goals — energy levels, sleep quality, joint comfort, digestion, mood, etc. Most supplements take 2-8 weeks for noticeable effects. For objective measurement, baseline lab tests before starting (and repeat at 3 months) provide definitive evidence. The Gabriel Score incorporates clinical evidence for expected outcomes.

Supplement information is provided for education and is not a substitute for personalized medical advice. Supplements are not intended to diagnose, treat, cure or prevent disease. Read the current product label before use.

Klean Athlete - Klean Casein Protein - Natural Vanilla Custard Flavor, 614 g