5.3. Effect of soil health on the nutritional value of plants for humans

Almost all minerals we ingest originate from soils or substrates and reach our bodies via the process of plants mineral uptake. Although nutrient sufficiency is literally of crucial importance for human existence, development and well being, there has not been much research on the relation between soil health and human health (Doran et al. 1996; Reeves and Coupland 2000). There has been quite some work on deficiencies and disease, but not that much on the promotion of health, at least until relatively recently this was a blind spot in science (Welch 2002). Doran et al. (1996) suggest three ways that soil health can impact human health: (i) direct toxic effects such as radioactive or chemical contamination, either naturally occurring or man-made, (ii) nutrient deficiencies or excesses, (iii) there might be a general positive effect of soil health itself on plant and animal health.