Micronutrients in the prevention of cancer – Part 2
It is believed that around a third of all cancer cases could be attributed to dietary and lifestyle factors. The link between nutrition and cancer risk is very complex, and it is difficult to establish the influence of individual dietary factors. The results of reviews have indicated that cancer-preventive diets above all consist of large quanti-ties of plant-based foods such as fruit, vegetables, whole grains and pulses. With a low energy density, these foods supply the body with plenty of fiber, as well as varying amounts of essential micronutrients such as vitamins, caro-tenoids, minerals and trace elements, which are thought to potentially influence the specific mechanisms by which can-cers develop. Several of these micronutrients are involved
in the maintenance of genetic information (Deoxyribonucleic acid, DNA) and may therefore be able to prevent the forma-tion of tumor cells.
Do we need recommended dietary intakes for phytochemicals?
Phytochemicals are biologically active compounds, found in plants in small amounts. At present, most interest in phytochemicals is focused on carote-noids and polyphenolic flavonoids, which seem to contribute to protection against degenerative diseases, such as cancer and cardiovascular disease. Mechanistically, phytochemicals are thought to act in many ways, which include their activity as antioxidants, antibacterial/ viral agents, phytohor-mones and as inducers or inhibitors of a variety of key en-zymes. Because of the large number of chemically different phytochemicals and the lack of a distinctive deficiency syn-drome or inherent physiological role in many cases, alloca-ting recommended dietary intakes to phytochemicals is problematic.
A new study reports that blood vitamin D concentrations of people living in São Paulo, Brazil, are good among the young and active during the summer, but not so in the winter, and that the elderly have poor levels year round.
According to a new US study, calcium is important for building strong bones in children, but, except for those with very low intake, may not be more important than magnesium.
