It takes intelligence to make intelligent choices. Sure, smart people can have great lapses in discipline, addictions, and so on, but overall they make better life choices than not-smart people.
More information does make a non-smart person smart.
Somebody need to explain Yogi Berra to me. LOL
Nutritional choices do make a difference in health and the condition of the brain. I’ve known some smart people who ate junk and went to total pot both physically and mentally. So, obstinate people of all IQ levels shoot themselves in the feet, sad to say.