mmm...better to understand the situation early whether ur hair loss is genetically, cause by oil block or unhealthy lifestyle (eating).
I was having this kind of problem that my hair losses was M shape. My problem is that my hair pores was blocked by oil thus become a skin coz not taken care of and dono what caused it that time.

Now I realise that, apart from that, I need to take care of my food intake. Most of our body need proteins and vitamins. We are encouraged to take >40 different types of food daily but we can't do that coz of our environment. Thus, that's where supplement comes into my life. to help my problem and increase my immune system as well.

If u r using gel or spray, have a better check around whether it will damage the hair or not and read the contents. Don't simply use it coz it is branded. For those dyeing hair one oso the same.