News from science and technology
Climate change and micronutrients
Climate change could have previously unknown effects on human health.
Scientists at Stanford University (California, USA) calculated the effects of the decline in nutrient concentrations by 2050 for the populations of 137 countries.
More CO2 in the atmosphere leads to less iron and zinc in many arable crops (rice and wheat) and thus to a potential deficiency. According to the study, these plants lose about ten percent of their zinc and iron concentrations. It is not yet quite clear why this is the case:
It is possible that the number of proteins in the plants containing these micronutrients may decrease. Plant growth is stimulated, but faster growth and earlier harvesting will probably also mean shorter time for plants to absorb nutrients during the growth phase.
Micronutrients are vital substances that humans have to take in with their food. These are mainly vitamins and minerals. Zinc is the decisive factor for the build-up of the body's own proteins and regulates the testosterone balance. Iron is necessary for the oxygen supply of the organism.
Cancer and influential lifestyle factors
A study recently published in the German medical journal Deutsches Ärzteblatt analyses the influence of lifestyle on the incidence of cancer.1
According to the study, the cancer risk in overweight is increased by 17% for gastric cancer, 33% for colon cancer, 83% for liver tumors, 67% for gallbladder cancer, 36% for pancreatic cancer and 154% for uterine cancer (among others). A reduction in physical activity (sports) to less than 100 minutes per week increases the cancer risk for colorectal cancer by 11%, pancreatic cancer by 3%, lung cancer by 20%, breast cancer by 7% and uterine cancer by 15%. If the consumption of red meat increases by 200g/week, the cancer risk for intestinal and pancreatic cancer increases by 3%. If the consumption of sausages increases by 200g/week, the risk of bowel cancer increases by 9% and breast cancer by 5%. Salt consumption increased by 2g/day increases the risk of stomach cancer by 5%. A decrease in ballast intake by 10g/day increases the risk of colon cancer by 11%.
Thus pathological overweight is responsible for approx. 30,000 new, avoidable cancer cases per year in Germany, too little physical activity for 27,000 cancer cases.
These results show that potentially influential lifestyle factors such as obesity, low physical activity and an unhealthy diet contribute significantly to the development of cancer in Germany.
1) Behrens G et al.: Cancer due to overweight, low physical activity and unhealthy diet; Dtsch Ärzteblatt Int 2018;115:578-85
Nature fertilizes better
The excrements of goats, sheep and cattle apparently fertilize the soil more sustainably than today's fertilizers. This is the conclusion reached by researchers at Washington University in St. Louis, who evaluated satellite images and soil samples of the Kenyan Savanna. Where up to 3700 years ago nomads locked their grazing animals in enclosures at night, the soil has since been rich in micronutrients such as phosphorus and calcium. Wild animals still gather in these places today because the plants thrive better there. 2
2) Stern 6.9.18: 20