The short answer is yes, 310nm UV light can generate Vitamin D, but it's not the most efficient wavelength for this process.
The optimal UVB wavelength for converting 7-dehydrocholesterol in the skin into Vitamin D is actually narrower and more intense, around 295–300 nm, with a peak near ~298 nm. Wavelengths shorter than 290 nm can also produce Vitamin D, but they are more likely to cause sunburn and are largely filtered out by the Earth's atmosphere.
Here's a breakdown of how 310nm light performs:
Effective but Compromised Efficiency
While 310nm light does trigger Vitamin D synthesis, its effectiveness is significantly lower compared to the optimal range. You might think of it as the "long tail" of the action spectrum.
Quantifiable Effectiveness: Research indicates that exposure to UVB light at 310 nm results in only about 21% of the Vitamin D production achieved at the peak wavelength. Another study using a narrow-band 310-320 nm lamp was shown to improve Vitamin D synthesis in mice.
Dose and Duration: This lower efficiency can be compensated for with longer exposure times. For example, one study found that a 90-minute exposure to 310nm UV light successfully generated Vitamin D₃ in chicks.
A Note on Very Long Wavelengths: It's worth noting that as you approach the end of the UVB spectrum, there's a critical point. Wavelengths above 310 nm are generally not effective and some sources even suggest they could degrade Vitamin D that's already been produced, rather than synthesize it.
Practical Context
Given its lower efficiency, 310nm UVB is not typically used in Vitamin D "supplement" lamps. Instead, its main applications are more specialized:
Psoriasis Treatment: Narrowband UVB lamps operating at 311 nm, such as the Philips TL-01, are a cornerstone of phototherapy for skin conditions like psoriasis. The therapeutic benefit is thought to be not only from Vitamin D synthesis but also from other anti-inflammatory effects triggered by this wavelength.
Reptile Lighting: In terrariums, it's crucial to provide the correct UVB spectrum. While the ideal peak for Vitamin D synthesis is around 294 nm, many high-quality reptile lamps (like the Exo Terra UVB200) aim to emit a broad range between 290-310 nm to ensure effectiveness.
If you are interested in a UV source specifically for boosting Vitamin D, a lamp designed to emit primarily in the 295-300 nm range would be a more effective choice. Artificial UV sources for this purpose should be carefully researched and used with caution, as UVB can damage the skin and eyes with overexposure , you can see more information for UVB LED Light on https://www.benweilight.com/lighting-tube-bulb/500-1-200w-75-000-180-000-lumens-super-bright.html
