If you had precocious puberty as a child, will that possibly affect your health as an adult?

Breast cancer. If you are female, your risk of breast cancer as an adult increases.
Depends on the cause. Most cases of precocious puberty are idiopathic, that is, we don't understand the reason yet. However, early puberty can also be caused by genetic hormone disorders, tumors, possible anatomical abnormalities in the brain, or be secondary to some other disease process. Therefore, when pubertal development occurs in girls < 8 y and boys < 9 y the child needs to go to the doctor for evaluation.
Not if you had care. If you received appropraite endocrine care as a child it shuld not affect you as an adult. If care was delayed you could have short stature and osteoporosis.