Vitamin D3

Kirkland Signature Vitamin D3 received a product quality score of 66/100 in GoodSupp's independent analysis, suggesting some areas that could be improved. The product contains 1 active ingredients Of the 4 inactive ingredients, 3 are rated safe and 0 are flagged for review. The manufacturer, Kirkland Signature, holds a brand trust score of 82/100 with 6 verified certifications including Consumerlab, Non Gmo Project, Usda Organic, Usp Verified.

Kirkland Signature Vitamin D3 contains 1 active ingredients: Vitamin E (as mixed tocopherol). Each ingredient's dosage, form, and safety rating is analyzed independently in GoodSupp's full product breakdown.

Kirkland Signature Vitamin D3 has been analyzed for ingredient safety across all its components. Always consult your healthcare provider before starting any new supplement, especially if you take medications or have underlying health conditions.

Kirkland Signature receives a brand trust score of 82/100 based on GoodSupp's independent analysis of certifications, regulatory history, and transparency practices. Founded in 1995 and headquartered in Issaquah, Washington, United States, the company offers 26 products in their lineup. They hold 6 verified certifications including Consumerlab, Non Gmo Project, Usda Organic, Usp Verified. Third-party certifications are independently verified and indicate the brand meets specific quality, purity, and manufacturing standards. Note: Kirkland Signature has 3 historical regulatory incidents on record, which are factored into the trust score.

The optimal dosage depends on your individual health needs, age, sex, and current nutrient levels. Recommended daily amounts are established by health authorities but may vary from therapeutic doses used in clinical research. It's important to check the Supplement Facts label for the exact amount per serving and compare it against the % Daily Value. Some supplements provide mega-doses well above the Daily Value, which may not be necessary and in some cases could be harmful — particularly for fat-soluble vitamins (A, D, E, K) that accumulate in the body. GoodSupp's efficacy analysis evaluates whether a product's dosages align with clinically studied amounts. Always consult your healthcare provider for personalized dosage recommendations.

This is an important question for supplement consumers. The dietary supplement industry is largely self-regulated, which means product quality, ingredient transparency, and safety practices vary significantly between brands and products. The most reliable way to evaluate any supplement is to check for third-party testing certifications, review the full ingredient list and dosages, and research the brand's regulatory track record. GoodSupp's database of over 250,000 analyzed products provides independent quality scores, ingredient safety ratings, and brand trust reports to help you make evidence-based decisions.

The optimal dosage depends on your individual health needs, age, sex, and current nutrient levels. Recommended daily amounts are established by health authorities but may vary from therapeutic doses used in clinical research. It's important to check the Supplement Facts label for the exact amount per serving and compare it against the % Daily Value. Some supplements provide mega-doses well above the Daily Value, which may not be necessary and in some cases could be harmful — particularly for fat-soluble vitamins (A, D, E, K) that accumulate in the body. GoodSupp's efficacy analysis evaluates whether a product's dosages align with clinically studied amounts. Always consult your healthcare provider for personalized dosage recommendations.