Without these additional compounds, synthetic nutrients are unlikely to be used by the body in the same way as their natural counterparts.

For example, studies show that natural vitamin E is absorbed twice as efficiently as synthetic vitamin E.

If you already consume a wide range of nutrients through your diet, taking extra supplements can exceed the recommended daily intake of many nutrients.

When taken in excess, water-soluble vitamins like vitamin C and B vitamins are flushed out of the body through your urine. However, fat-soluble vitamins — vitamins A, D, E, and K — may be stored in the body. This means that there is a risk of them accumulating to high levels, leading to hypervitaminosis.

Reference- https://pubmed.ncbi.nlm.nih.gov/17209208/