Sulfate:
Sulfates are types of chemicals called surfactants, they play a significant role in the effectiveness of shampoos. Surfactants makes the liquid easier to mix with water and create good foam. 
Foam in shampoos makes it easier to spread the shampoo through our head. To add, it helps any active ingredients in the shampoo work deeper into the hair to remove dirt and excess oils.
Is Sulphate Dangerous?
Sulphate might be negative to the hair where when it removes the dirt away, it takes some of our hair’s natural oils that we need to stay healthy. In addition, it takes a bit of our hair’s natural moisture and as a result, the hair becomes dry and unhealthy. The scalp can get affected too, sulphates can cause dryness and prone to irritation in the scalp.
The “MedicalNewsToday” discussed a review that looked at the possible toxicity of sodium lauryl sulfate. The researchers noted that much of the negative public view of sulfates might be due to how people have understood the scientific reviews.
However, the hair benefits from the sulphate in shampoos especially people with dandruff or greasy hair will need sulphates to clean the hair.
Who Should use Sulphate-Free shampoos? 
- People with sensitive skin or skin conditions
According to MedicalNewsToday “Those with a skin condition such as eczema or psoriasis who use shampoo containing sulfates may also experience itching, redness, and cracking in their scalp after use. These people could consider using sulfate-free shampoos.”
- Dry, Frizzy Hair People
Sulfates will increase the dryness and frizziness of hair because of the high friction caused by the clearing of the natural oils and moisture.
- People with dyed or bleached hair
Shampoos with sulphates can strip the color easily from the hair