Research papers in the notes below the video. This may give you some reassurance.

https://www.youtube.com/watch?v=IjQColM-q44

An associated one.  https://www.youtube.com/watch?v=QadlpylF-tw

Research links in the notes of the second video too. Yeah!

I have heard the same thing from some of the other doctors, but this one is the first I ran across. Dr Ken Berry is one doctor worth listening to every video he has produced. He does not sell anything. Just wants to help people and realizes he has given a lot of bad advice to his patients in the past. He got to I think 270 pounds before starting out on his own journey of healing and weight loss, researching why his recommendations to his patients in the past were bad and now trying to rectify that. Also, he normally puts links in the notes below his videos to the research papers he uses in making his determination. That lends credibility in my opinion. I find him a very credible source.

I also really like Dr Ken Berry because he stays on subject, doesn't ramble, and keeps his videos short, sweet and to the point. He is easily my number one favorite health "guru" because of the way he does things.

John