II. What we need to eat
Some substances are not generally considered essential to man, but might become so under specific circumstances (that is, conditional deficiencies are possible). Here are some examples:
- Carnitine can be synthesized in adequate amounts by normal individuals, but synthetic capacity could be compromised in liver disease, or shortly after birth (when synthetic capacity is not fully developed), etc.
- Inositol --
- may be beneficial in diabetics (improved nerve conduction velocity).
- may improve lung development in small pre-term infants with respiratory distress syndrome.
The existence of conditional deficiency states may give rise to exaggerated claims of the importance of certain substances in normal individuals' diets, leading to recommendation of unnecessary routine supplementation, etc.