You may get some side effects like low energy, low blood sugar levels, fatigue, dizziness and body aches, etc.
If you are doing detoc diet, you are going to go without a lot of foods you usually eat.
If you are having proper healthy meals, avoiding packaged foods, your body doesn't need any detox diet.
The only type of detox that is worthwhile is regular excercise, limit processed foods, high fat and sugar foods and replace them with green veggies.
This clean eating approach is best way to get your body to be fit and healthy.