There are a few things that may help to stop or slow hair loss in teenage guys:

  1. Maintain a healthy diet: A healthy diet that is rich in protein, iron, and other nutrients can help to support hair growth.
  2. Avoid tight hairstyles: Tight hairstyles, such as cornrows or ponytails, can cause traction alopecia, a type of hair loss that is caused by pulling on the hair.
  3. Avoid using harsh hair products: Using harsh hair products, such as those that contain alcohol or sulfates, can strip the hair of its natural oils and lead to dryness and breakage.
  4. Avoid stressing the hair: Try to avoid excessive brushing, blow drying, and styling, as these can all contribute to hair loss.
  5. Talk to a dermatologist: If you are experiencing hair loss, it is a good idea to talk to a dermatologist. They can help to determine the cause of the hair loss and recommend appropriate treatment.
  6. Consider using minoxidil: Minoxidil is a topical treatment that is available over the counter and has been shown to be effective at promoting hair growth. It is worth discussing with a dermatologist to see if it is a suitable option for you.