Yes, it is recognised as a potential problem: LED lighting flicker and potential health concerns: IEEE standard PAR1789 update.
The IEEE Standards Working Group, IEEE PAR1789 “Recommending practices for modulating current in High Brightness LEDs for mitigating health risks to viewers” has been formed to advise the lighting industry, ANSI/NEMA, IEC, EnergyStar and other standards groups about the emerging concern of flicker in LED lighting. This paper introduces power electronic designers for LED lighting to health concerns relating to flicker, demonstrates that existing technologies in LED lighting sometimes provide flicker at frequencies that may induce biological human response, and discusses a few methods to consider when trying to mitigate unintentional biological effects of LED lighting.
The physiological pathway is that all humans are sensitive to flickering light - the range of sensitivity in both frequency and intensity varies by individual. At normal mains frequencies (50 or 60Hz) the vast majority of the population is insensitive but some people are.
This 2011 (unpeer-reviewed?) article, Exploring flicker in Solid‐State Lighting:
What you might find, and how to deal with it discusses it further, showing the different sorts of flickering that occurs from different types of light sources, plus a brief summary (with references) of some of the health effects flickering can cause, including this excerpted list:
- Headaches and eyestrain
- Neurological problems including photosensitive epilepsy
- Reductions in visual performance
- Disruptive behaviors in individuals with autism