But Not Too Much Nutritionists are very careful when they say that a nutrient is essential in the human diet. This is particularly true when it comes to minerals, because some minerals taken in high concentrations can be toxic. Most minerals are required in very minute amounts, and proving that a trace mineral is essential for health is a very difficult task. It is hard to find a definitive list of minerals that everyone agrees are essential for humans. But we have to be careful.
Plants often contain minerals that are taken up from the soil they are grown in.
When it comes to supplementing common foods with essential nutrients one of the concerns is that, if too many foods we usually eat contain added minerals, and, if at the same time people are taking supplements, there is a very real possibility that mineral toxicity may be a problem.