By: Eric C. Brevik, Ph.D. (Department of Natural Sciences, Dickinson State University) & Lynn C. Burgess, Ph.D. (Department of Natural Sciences, Dickinson State University) © 2014 Nature Education
Citation: Brevik, E. C. & Burgess, L. C. (2014) The Influence of Soils on Human Health. Nature Education Knowledge 5(12):1
Soils are important for human health in a number of ways. Approximately 78% of the average per capita calorie consumption worldwide comes from crops grown directly in soil, and another nearly 20% comes from terrestrial food sources that rely indirectly on soil (Brevik 2013a). Soils are also a major source of nutrients, and they act as natural filters to remove contaminants from water. However, soils may contain heavy metals, chemicals, or pathogens that have the potential to negatively impact human health. This article will summarize some of the more important and direct relationships between soils and human health.
Quality Food Production and Food Security
Quality food production and food security have several components, including the production of sufficient amounts of food, adequate nutrient content in the food products, and the exclusion of potentially toxic compounds from the food products (Hubert et al. 2010). Soils play a major role in all of these areas of quality food production and security.
Influence of Soils on Crop Yield and Food Security
Food security is achieved when all people have access to sufficient, safe, and nutritious food (Food and Agriculture Organization of the United Nations, 2003). Food security is central to human health (Brevik 2009a; Carvalho 2006), and the ability to produce nutritious crops in sufficient amounts depends on soil properties and conditions. In particular, soils that have well-developed structure, sufficient organic matter, and other physical and chemical properties conducive to promoting crop growth lead to strong yields and are thus important for food security (Reicosky et al. 2011; Brevik 2009b). Soil degradation, which includes soil erosion and loss of soil structure and nutrient content, decreases crop production and threatens food security (Brevik 2013b; Pimentel & Burgess 2013; Lal 2009) (Figure 1). Soils that contain substances such as heavy metals, which may be toxic to humans, can pass those substances on to humans through crop uptake, leading to unsafe foods that compromise food security (Hubert et al. 2010; Brevik 2009a).
Figure 1: Soil degradation along the top of the hill has left the soils unable to support strong plant growth. Soil degradation over large areas may threaten food security.
Photo by Gene Alexander, USDA NRCS