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 Lauryl Sulfate is a surfactant. It helps cosmetic products to remove all the sebum and dirt from your skin. Water can't dissolve sebum on its own because sebum contains oils. Surfactants help water get into sebum and wash off all the unnecessary stuff from your skin.
The component also helps to form a nice foam. The foam allows to spread the product evenly. which is important for good cleansing.
The component is researched quite well. Studies showed that it doesn't have any negative impact on human health if you apply it to your skin. It can be toxic only if you take SLS inside, but we doubt that somebody likes to drink shampoo or eat soap.
However, the component has its negative side. It can dry out skin or hair too much. You can suffer from this effect if you have dry skin. Plus it can make your hair less protected because natural sebum works like a barrier. Washing it off completely isn't the best idea.
Glycerin is one of the most outstanding and helpful skincare components. It's used in many skincare products because it works and provides notable results. It's one of the best moisturizers. Molecules of Glycerin can absorb water and deliver it into deep layers of the skin making it hydrated.
The component is researched very well. Many scientific researches confirm the safety and the efficiency of the component.