Understanding the interactions, benefits, and safety of combining these two powerful supplements.
We found no documented interaction between Biotin and NR 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.
What it is: A B vitamin that helps turn the food you eat into energy.
What the research says: It's widely sold for hair, skin and nails, but there's little evidence for that. A few small studies found harder nails in people with brittle nails.
In Holitro: Biotin 5000mcg (5000 mcg per capsule)
Source: NIH Office of Dietary Supplements: Biotin: Fact Sheet for Consumers (updated January 2021)
What it is: A form of vitamin B3 that the body uses to make NAD+, a molecule involved in energy production.
What the research says: It reliably raises NAD+ levels and was well tolerated for weeks to months in trials, but effects on health and aging have been mixed or absent.
In Holitro: NR (500 mg per capsule)
Source: PubMed review: NAD+ supplementation for anti-aging: systematic review (2026) (updated February 2026)
Check with your doctor or pharmacist, especially if you take medication.
Check your stack β freeEducational 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.
Balancing dosages across multiple different bottles is risky, inefficient, and expensive. Taking too much of one can blunt the absorption of the other.
Holitro completely solves this. We combine synergistic ingredients into one perfectly dosed daily pack, scientifically formulated for maximum absorption.