Almost all of his diet/neuroscience/health claims (outside of commonly known things, like "exercise is good for you") are at best a gray area, and at worst just flat wrong. That is because we really don't know much about the brain and its relationship to human experience and behavior - and so anyone claiming to know how to improve your life with "neuroscience" is a con artist. Same with diet, which he also harps on constantly.
For almost every non-obvious claim he makes about something, there exist studies that directly contradict him. And, being a good con artist, he conveniently ignores them. Here are some things he has claimed that are not at all settled science, although he talks as if they are and leaves out the contradictions:
- Artificial sweeteners cause insulin resistance
- Light alcohol consumption is detrimental
- You can "hack your brain chemicals" with supplements to achieve some desired effect on your mind
- We know what role neuromodulators play on really high level cognitive concepts like "creativity"
- Increasing the diversity of your gut microbiome has positive health effects
Frankly, no one's life will be any different from listening to Huberman or from doing anything he tells you to do, aside from those things everyone already knows about (like exercising, sleeping an appropriate amount, and not eating a bunch of refined sugar). If there IS some change outside of those, it is just as likely to be the result of random chance than from taking Huberman's advice, because there is no evidence that anything he says (outside of the obvious) is actually beneficial or worthwhile.
To your question - yes...it absolutely DOES need a scientific study. Huberman's claim is porn literally DESTROYS YOUR BRAIN. But again, the studies are terrible and there are many contradicting studies that he would never point out - he's trying to make you think he knows what he's talking about and has something worthwhile to say (when he actually doesn't).