If i stop eating polyunsaturated fats, how long does it take for them to completely be out of my body?

Incomplete diet: Wow that would be difficult to do! Building a diet that has NONE is tough. Further the body can or modify small amounts of certain types of polyunsaturated fat compounds, so they are always present. More importantly, a certain amount of "good fats" is highly valuable for health. Consider consulting a dietician to help you identify the best nutrition plan for your individual needs.