Certification status
USP Verified
Kirkland Signature Kirkland Signature Calcium 600 mg with Vitamin D3 Tablets
Kirkland Signature Calcium 600 mg with Vitamin D3 tablets — Costco's house-brand calcium-plus-D combo. 600 mg calcium per tablet, with D3 alongside. USP Verified, meaning identity, purity, potency and manufacturing quality have been independently checked. Note: USP verification is not banned-substance testing. Amazon UK lists at £59.99 — Costco-scale pack.
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Why this certification matters
- USP Verified
- USP Verified products meet the United States Pharmacopeia standards for ingredient identity, potency, and manufacturing quality.
Frequently asked questions
- Is this the same as Costco's in-store calcium?
- Yes — Kirkland Signature is Costco's house brand, and the Amazon UK listing reflects the same line.
- What does USP Verified actually test?
- USP Verified checks identity (what's listed is what's in the bottle), purity (contaminants below specified limits), potency (label dose matches actual content) and manufacturing quality. It is not a banned-substance certification.
- Is this suitable for tested athletes?
- USP Verified is a strong manufacturing-quality cert but it does not screen for banned substances. Tested athletes who want banned-substance assurance should look for NSF Certified for Sport, Informed Sport or Informed Choice.
- Why so many tablets per bottle?
- Kirkland packs are typically Costco-scale — large bottles aimed at long-term value per pill. That's reflected in the £59.99 Amazon UK price compared with smaller pharmacy calcium tubs.
- When should I take calcium with D3?
- Calcium is best taken in split doses with food and away from iron supplements (which compete for absorption). The D3 component is fat-soluble and benefits from a meal containing fat.
