Short answer

We found no documented interaction between Glycine and Green coffee 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 coffee extract

What it is: An extract of unroasted coffee beans, rich in chlorogenic acid.

What the research says: Small, short trials found modest drops in body weight (about 1 kg), blood pressure, cholesterol and fasting blood sugar.

Cautions

• Most studies were small and short. Extracts may contain caffeine.

Medicines to check

• Talk to your clinician if you take any medicine

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

Sources: PubMed review: Chlorogenic acid in green coffee on body weight: meta-analysis (2023) (updated September 2023); PubMed review: Green coffee bean extract and cardiovascular risk factors: meta-analysis (2021) (updated October 2026)

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.