Many plants and herbs have been known for healing a variety of health
disorders since the ancient practice of medicine. Recent advances in laboratory
methods have now identified the chemical compounds in plants (phytochemicals) that
are responsible for the health-promoting effects. There are thousands of
phytochemicals known so far which have no nutritional value but can help in many
biological processes in the human body. The phytochemicals mainly include
flavonoids, carotenoids, phenolic acids and lignans. They play a role in many body
functions and are equally important as micronutrients in maintenance of health and
wellbeing. The synergistic actions of phytochemicals and micronutrients as
antioxidative and anti-inflammatory agents may contribute towards disease prevention
and betterment of health. Food sources of phytochemicals, their role in various
metabolic functions, and health effects are described in this chapter. Gut microbiome,
which comprises of intestinal microbial population, performs important functions like
digestion of food, regulation of immune system and shares an interactive relationship
with dietary nutrients and non-nutrients. Phytochemicals that can influence the gut
microbiome have recently been studied as adjuvants for the treatment of obesity,
diabetes, cardiovascular disease and inflammatory diseases. The effect of different
phytochemicals on gut microbiota and their beneficial health effects are elucidated.
New developments related to potential of probiotics as prophylaxis or their therapeutic
use in treating the COVID-19 infection is briefly mentioned.
Keywords: Antioxidants, Bacteroidia, Bifodobacteria, Carotenoids, Colour pigments, Diabetes, Dietary fibre, Dietary sources, Enzymes, Flavonoids, Gut microbiome, Health effects, Lactobacilli, Lycopene, Micronutrients, Obesity, Phytochemicals, Polyphenols, Prebiotics, Probiotics.
