Current scientific evidence does not support the idea that natural vitamins are more effective than synthetic ones; studies show that synthetic and organically or naturally sourced vitamins exhibit similar bioavailability and circulatory profiles.
The claim asserts that vitamins from natural foods are more effective than synthetic supplements. However, direct empirical studies comparing organic/natural versus synthetic micronutrient supplementation (e.g., paper 8) find no significant differences in circulatory profiles, indicating they are functionally comparable. Furthermore, broader reviews on micronutrient bioavailability (paper 3) note that supplementary vitamins are at least as bioavailable as those found endogenously in foods. Therefore, the available evidence refutes the claim.