Water is a great solvent. It’s neutral and doesn’t provide any strong positive or negative effects. It just helps components to mix better and to transport active components.
Sodium Citrate is a water-soluble soft organic surfactant with strong stabilizing and conditioning effects. It helps to produce foam and lowers the negative impact of hard water on your skin and hair. It also helps to regulate the pH level of the product. It’s a natural ingredient and it’s safe for most people. It’s used in food (additive number E331).
Citric Acid is one of the AHAs and it is a super useful component! It’s a great antioxidant. It acts as a soft peeling that removes dead cells and kills bacteria. It becomes even more effective if used with other cosmetic acids. Combined formulations are more active, but can irritate sensitive skin if used too often. The component can also whiten the skin and remove dark areas.
It's an exfoliator, meaning it increases UV sensitivity of your skin. That's why it's very important to use sunscreen after it.