PURPOSE: To characterize age-related changes in the transmission of light through noncataractous human lenses. SETTING: Department of Ophthalmology, Glostrup Hospital, Glostrup, Denmark. METHODS: The spectral transmission of white light was measured along the visual axis in the most central part of the lens in vitro in intact human donor lenses over a wide range of ages. RESULTS: The study evaluated 28 intact human donor lenses of 15 donors aged 18 to 76 years. Increasing age was associated with gradually decreasing transmission at all visible wavelengths, most prominently at shorter wavelengths. Empirical formulas describing the age-related loss of transmission were created for each spectral color. At 480 nm, the absorption peak for melanopsin, transmission decreased by 72% from the age of 10 years to the age of 80 years. CONCLUSION: The age-related decrease in spectral transmission through the human lens could be modeled by a simple algorithm that may be useful in the design of intraocular lenses that mimic the characteristics of the human lens and in studies of color vision, psychophysics, and melanopsin activation. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.