Vitamin A (retinol) is not dosed based on percentages but on international units (IU). One IU of vitamin A is the biological equivalent of 0.3 micrograms retinol or 0.6 micrograms beta-carotene. Vitamin A Microcaps contains about 1.7mio IU retinol (or 0.5g retinol) per 100 grams. Or one gram of the Microcaps solution contains about 17'000 IU retinol. The recommended use level of Vitamin A Microcaps is about 5% (= 5g or 1 tsp per 100g cream). Please note that this use level does not refer to the retinol concentration but to the concentration of Microcaps solution. In other words, you have to add only about 5% of the Microcaps solution to your products. The final retinol concentration in the finished product will then be about 85'000 IU per 100g of cream which is more than enough to supply the skin with vitamin A. Some commercial products contain up to 300,000 IU retinol per 100g of cream, but the retinol is not micro-encapsulated. Clinical studies have shown that micro-encapsulated retinol is protected from degradation and its absorption into the skin is enhanced several times over non-encapsulated retinol.