the problem with refined carb is it is highly addictive.
anyone that switched over to whole grain bread/rice/pasta will agree a single serving now seem to be plenty when in the past 2-4 servings would be the norm.
fruits are good in moderation. just don’t drink fruit juices. they may have lots of vitamins, but they are essentially concentrated sugar with the fiber removed.
as for the fat. in moderation of course. you can’t survive on a NO fat diet. but too much fat WILL raise your cholesterol, this is not a conspiracy driven advice.