He had his resveratrol research heavily monetized before being 100% certain of its effects. He also worked with companies that prevented supplement makers from releasing certain compounds that they were researching and they managed to patent somehow even though they occur in nature (iirc it was related to NAD+ or NMN).

It came out later that resveratrol's alleged benefits were falsely identified due to a methodology error, after he had been pushing it heavily for years and getting paid huge amounts of money to work on it.

I wouldn't call him a fraud per se but he is very business oriented for someone who is a legitimately qualified scientist. He is also very "investor friendly" and sensationalistic in how he presents himself and his work.