Why is it unwise to avoid certain categories of foods all together or to only eat some categories of foods as suggested by fad diets?

The simplest answer is that it can cause nutrient deficiency or essential body organs to not work properly. Some fad diets suggests that you avoids the fats food category, yet fat is essential to normal body function as there are healthy fats that are needed to help transfer nutrients

This is what i found on google “phytoplankton, tiny organisms that live in the ocean, are autotrophs. some types of bacteria are autotrophs. most autotrophs use a process called photosynthesis to make their food.” i hope this you for what your looking for