All Supplements
L-Glutamine vs L-Theanine
Side-by-side comparison — benefits, dosage, forms, and research.
Feature
L-Glutamine
L-Theanine
Typical Dosage
5-10g daily
100-200mg daily
Best Form
L-Glutamine powder
L-Theanine (Suntheanine)
Key Benefits
5
5
Evidence Rating
★★★
★★★★
Best Time
Post-workout or divided throughout the day with meals
With caffeine for focus, or evening for relaxation
L-Glutamine Benefits
✓Supports intestinal barrier integrity
✓Enhances immune cell function
✓Promotes muscle recovery and protein synthesis
✓May improve gut health and reduce leaky gut
✓Supports nitrogen balance during catabolic states
L-Theanine Benefits
✓Calm focus without sedation
✓Reduces caffeine jitters when combined
✓Promotes alpha brain waves (relaxed alertness)
✓May improve sleep quality
✓Anxiety reduction
Can You Take Both Together?
In most cases, L-Glutamine and L-Theanine can be taken together safely. However, always check the interactions section of each supplement and consult a healthcare professional if you take medication.
Which Should You Choose?
Choose L-Glutamine if your primary goal is: supports intestinal barrier integrity. Choose L-Theanine if your primary goal is: calm focus without sedation. Many people take both as they target different aspects of health.
Disclaimer: This comparison is for educational purposes only. Always consult a healthcare professional before starting any supplement.