Someone asked me recently 'what was the big take home message or most important thing you learned doing your Masters?'. The Masters was in nutrition and health, so you might think there's some big 'a-ha' moment with food or fat loss or something food related.
The most important thing I have learned in the nutrition and exercise space as a whole has been the ability to think critically.
Critical thinking skills are something I think literally every person on the planet should know about. Do they teach critical thinking in school? If not, they should.
Once you know and understand what they are, they'll be a permanent fixture in your mindset for the rest of your life.
The video is short and gives an overview of the main principles, but there are plenty of resources online you can look for if you want to delve in more.