1.Avoid Shampoos that contain sulfates: A popular ingredient today that could be found in many shampoos (especially cheap ones) is sulfate these ingredients generally end in sulfate and are usually called sodium lauryl sulfate or sodium laureth sulfate the reason why using a shampoo with this ingredient is bad,is because sulfate is known for being a harsh surfactant or disinfectant , it is even used for dish soap, laundry soap, etc. The sulfate in some shampoos causes your hair to lose it's essential oils and for some people it causes them to produce too much oil from using it too often. This ingredient is especially bad for people who have curly hair or colored hair (it takes out the hair dye) as well.
What you could do is that you could replace your sulfate shampoo with sulfonate shampoo almost any shampoo should be okay as long as it does not contain sulfates. 2.Avoid Silicones : This ingredient is a little more tricky to find but generally, silicones are ingredients that end in -col -cone -conol and -xane some examples would be trimethicone, dimethicone , dimethiconol etc. The reason why this ingredient is bad is because it creates a barrier or a coat on your hair this barrier/coat could lead to build up and that is not healthy for your hair. The only way to get rid of silicones is to use a hard shampoo with sulfate be careful though because some shampoos contain silicones as well. However, it is believed that the barrier that silicones create are pretty useful for heat damage so when you straighten your hair or curl it it is good for you to use silicones if you wash it out later. But if you're going to be leaving your hair natural then using silicones wouldn't be a good idea. Also keep in mind that there are water soluble silicones that are okay to use and they usually start with PEG or PPG
3. Parabens: parabens are commonly used in body lotions some examples of parabens methylparaben,propylparaben, butylparaben, etc. Parabens are a serious danger because it is known as one of the causes of breast cancer And this is a big deal because there are not many known causes of breast cancer.