Too much fat & carbs in the same diet causes problems. That's what the SAD is. Protein & fat is low-carb which causes problems longterm also. No macro is excluded, just eaten in the correct ratio.
Every person can eat this way, most have been frightened to by all the anti-carb propaganda. There's plenty of carbs to choose from if a certain group of carbs, such as grains, don't seem to digest well for people, but that's usually because they are eating too much fat or protein. All successful civilizations relied on starches for their main source of calories.
"Low-fat" is considered anything under 20% calories coming from fat. The people I trust most recommend nothing higher than 10-15%.
You seemed a little upset for me merely suggested you try a low-fat diet if you're still having health problems. Why?