Short answer

We found no documented interaction between Calcium and Glycine 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.

Calcium

What it is: The body's most abundant mineral; it builds bones and teeth and helps muscles, nerves and blood vessels work.

What the research says: Calcium supports bone health, especially when diet falls short. Vitamin D helps the body absorb it.

Cautions

• Upper limit from all sources: 2,500 mg a day for adults 19 to 50, and 2,000 mg from age 51.
• Some research links very high intakes to heart disease and prostate cancer risk.

Medicines to check

• Levothyroxine (thyroid medicine): keep doses apart
• Quinolone antibiotics: keep at least 2 hours apart
• Dolutegravir (HIV medicine) and lithium

In Holitro: Calcium Citrate (160 mg per capsule)

Source: NIH Office of Dietary Supplements: Calcium: Fact Sheet for Consumers (updated September 2023)

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)

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.