This should be brief as you have either already noted my concerns about the use of supplements and acted accordingly, or you are choosing to ignore the evidence because you just like to spend money. You probably feel like you are doing the proactive thing to improve your health and I am not going to be able to convince you otherwise.
The truth is that the majority of persons do NOT need to take any vitamin or mineral supplements as a well balanced diet will provide the correct amounts of both. A few people may be deficient in something, but it isn't usually the something you think it is.
This month the consumer group Public Citizen released a user's guide for vitamins and minerals. The persons that are most likely to need supplementation are older and do not consume enough calories, OR the calories that they consume are empty or junk calories. Other persons who may need supplementation include those recuperating from injury, surgery or illness. The organization strongly encourages any one who wants to supplement to talk to their physician. There is a risk of taking too much of something and NO evidence to suggest that taking more of that which is recommended is of any help. Public Citizen recommends that you buy the least expensive product and the no name brand. They also say that there is no benefit to buying one that claims to be all natural and that the companies who sell these products sometimes charge 1000 times their cost.
The vitamin I hear the most about is Vitamin D and I suggest that all of you talk to a health care professional regarding your need for this in a supplement. Other wise, it is more likely that a person will need a mineral, like zinc, iron or magnesium than a vitamin, like C.
Which brings me to my last point. Eating a diet rich in fruits and vegetables while also taking care of your body with regular physical activity is the best way to avoid colds and such. The products sold to enhance your immune system are just ridiculous wastes of money in my humble opinion! HA since when am I humble...