Short answer

We found no documented interaction between Glycine and Green tea extract in the sources below. That isn't proof the combination is right for you: check each one's cautions, and ask your pharmacist if you take medication.

Glycine

What it is: An amino acid the body makes; it's a building block of creatine, glutathione and collagen.

What the research says: Some studies suggest it may improve sleep quality and recovery, but reviews say more good human trials are needed.

Cautions

• No major safety concerns are reported at supplement doses; human research is limited.

Medicines to check

• Talk to your clinician if you take any medicine

In Holitro: Glycine (850 mg per capsule)

Sources: PubMed review: An Update of the Promise of Glycine Supplementation (Sports, 2024) (updated September 2024); PubMed review: Multifarious Beneficial Effect of Glycine: A Review (2017) (updated March 2017)

Green tea extract

What it is: A concentrated extract of green tea leaves, rich in catechins such as EGCG. It contains caffeine.

What the research says: Catechins and caffeine may have a modest effect on weight, and it lowered LDL cholesterol a little. Cancer results are inconsistent.

Cautions

• Extracts can cause nausea, constipation, stomach discomfort and higher blood pressure.
• Liver injury has been reported, mainly with extract capsules; a gene variant found in 5 to 15% of Americans raises the risk.

Medicines to check

• Nadolol (a beta-blocker): green tea can lower its levels
• Atorvastatin (a statin) and raloxifene (an osteoporosis drug)

In Holitro: Green Tea Extract 500mg (500 mg per capsule)

Source: NIH National Center for Complementary and Integrative Health: Green Tea: Usefulness and Safety (updated February 2025)

Check with your doctor or pharmacist, especially if you take medication.

Check your stack — free

Educational information only, not medical advice. This reflects general ingredient overlap, not a personalized safety review. Always check with your doctor or pharmacist before combining supplements, especially if you take medication, are pregnant or nursing, or manage a health condition. These statements have not been evaluated by the FDA.