Надо поставить: who, that, which, whose, where or when. when.
1. I don`t know anyone has been on a fast.
The food I had last night wasn`t very healthy.
2. There is at least one person in my family eats meat every day.
I tend to go to restaurants they serve healthy food.
3. New Year is a time I always eat too much.
I don`t know anyone lifestyle is really healthy.