In her blog, Nestle explains two approaches to understanding vitamin supplements — one based on beliefs and the other on science. (Interestingly, she says both are viable.) She writes:
Supplements are a good example of how scientists can interpret research in different ways, depending on point of view….
For example, on the need for supplements, a belief-based approach rests on:
–Diets do not always follow dietary recommendations.
–Foods grown on depleted soils lack essential nutrients.
–Pollution and stressful living conditions increase nutrient requirements.
–Cooking destroys essential nutrients.
–Nutrient-related physiological functions decline with age.
A science-based approach considers:
–Food is sufficient to meet nutrient needs.
–Foods provide nutrients and other valuable substances not present in supplements.
–People who take supplements are better educated and wealthier: they are healthier whether or not they take supplements.
The statements in both approaches are true.