The problem is that all such lists of vitamins and minerals and not only the RDAs refer to a statistical average or norm. But you are neither an average nor a norm. You are a unique individual from every point of view, with all the pluses and minuses that nature, your ancestry, your genetic code and blood group, your living and eating habits etc, have endowed you with. Uniqueness is not subject to the average, the typical, the standard or the mainstream. Let me explain by taking two actual examples from my own practice.
If you have a history of cancer in the family and you also happen to like your hot-dogs or your knackwurst, you may know that you need extra vitamin B6 for fat metabolism. What you may not know is that you also need ample amounts of vitamins C and E, well above any RDAs. This is to protect you from the carcinogenic nitrosamines formed in your body, from the nitrous salts placed in all processed meats to prevent botulism, the worst kind of food poisoning that could virtually kill you overnight. Family medical history and personal food choices place you in an endangered category that requires care and a special regimen of vitamins.
Now let us take a different case involving minerals this time. If you happen to form kidney stones easily, you may have been advised to cut down on calcium- and oxalate-rich foods. I will not discuss here how sound this advice is, but simply what may happen. Depending on your sex, age, and predisposition, a calcium deficiency may develop sooner or later, which may readily cause a manganese excess in your body. The excess manganese may depress potassium levels, which in turn may allow an excess of sodium to accumulate. Note that these mineral relationships and interactions are real and well known; they are not theoretical considerations.
So although there is no direct link between calcium and sodium, a calcium deficiency may indirectly cause a rise in your blood pressure. This is what often happens in post-menopausal women. If you come from a family with a history of strokes or other blood pressure related disorders, this is not at all an optimistic prospect. What is worse, it may be difficult to understand the sudden rise in your blood pressure, unless the attending health care professional is fully aware of these micronutrient interactions. But as many primary care physicians readily admit, few of them are aware of such interactions. This is perfectly normal, since they have not been trained in nutrition.
I could cite hundreds of relevant cases from my own practice and thousands from the literature, but the gist of my argument is that it is easy to find an approved list of vitamins and minerals for the average or norm. It is even easier to take them, since many firms manufacture pills or capsules containing a large variety of micronutrients in manifold combinations.
But knowing exactly what vitamins and minerals to take and how to take them, for your particular circumstances, of genetic predisposition, family medical history, food choices and eating habits, present lifestyle and health condition and all these things that distinguish you as an individual, is neither easy nor simple. It requires expert knowledge, long experience, but also a conscientious effort to examine all the variables involved, and especially their possible interactions.