Vitamin supplementation may have its place in clinical nutrition, but confusion of how or when to supplement can ultimately harm the consumer.(1) The confusion arises from "extreme" views of healthcare practitioners who say supplementation is not necessary at all and those who push for too much supplementation.(1p119) Non-credentialed experts and vitamins manufacturers interested in making profits may also lead consumers in the wrong paths.(1p119)
Pros of Supplementation
As a person ages or changes his or her diet or environment, vitamin needs can change resulting in a potential need for help from vitamin supplementation.(1p119)
Supplementation can remove the guesswork out of making sure enough of a certain vitamin is in the diet. A woman, for example, who has a need for additional folic acid during times of pregnancy may choose supplementation rather than attempting to make significant changes to diet.(1p119) A child or adolescent can also be given supplements to be sure of healthy growth despite a reluctance to eat a balanced diet.(1p119)
Supplementation can be used to prevent clinical issues.(1p119) An example includes infants given vitamin K and D and trace minerals iron and fluoride.(p119)
Impaired nutrient absorption, storage and usage can be helped by supplementation.(1p119) An example includes elderly who may may need vitamin C, thiamin, riboflavin, pyridoxine and cobalamin.(1p119)
Lifestyle choices may influence need of supplementation.(1p120) Use of oral contraceptives, restricted diets, exercise programs, smoking, alcohol and caffeine can all generate situations of vitamin deficiency due to insufficient dietary intake and/or interference with absorption of vitamins.(1p120)
Certain diseases may create a situation where a person could benefit from supplementation.(1p120) Especially in cases of long-term illness, supplementation can be used to meet increased vitamin needs to support the body.(1p120)
Cons of Supplementation
While there are many "pros" to vitamin supplementation, the "cons" can be equal in detriment. A large amount of a certain vitamin can be toxic such as the case of retinol, which has potential of causing liver or brain damage.(1p120)
Megadoses of vitamins can also lead to a deficiency of another vitamin due to how they work together in the body.(1p120) An "artificially induced" deficiency can result when a person suddenly stops taking a large amount of a certain vitamin, such as infants who develop scurvy because their mothers took megadoses of vitamin C during pregnancy.(1p121)
A non-credentialed "expert" or vitamin manufacturer may miss these points as he or she recommends or markets certain vitamins to unsuspecting customers.
Proper vitamin supplementation should be done with wisdom and care. Supplementation principles include reading labels carefully, understanding that large doses can be harmful, that supplement use is governed by individual needs, that all nutrients work together, and that food remains the best source of nutrients.(1p121) Lastly, sound knowledge and evidence should guide reasons for supplementation.(1p121)
1. Nix, S. Williams' Basic Nutrition &Diet Therapy, 12th ed, Elsvier Mosby, 2001; 119-121.