Potential Health Benefits and Problems Associated with Phytochemicals in Food Legumes
Phytochemicals are a naturally occurring group of chemicals in plants and plant-derived foods. Presence of phytochemical components such as phytohemagglutinins, tannins, phytic acid, saponins, protease inhibitors, oligosaccharides and phytoestrogens in food legumes has both health benefits and adverse effects. These have been associated with numerous health benefits, including reduced cardiovascular and renal disease risks, health care treatments including anti-aging, enhancement of brain function, lower lycemic index for persons with diabetes, increased satiation and cancer prevention. Health benefits resulting from ingestion of oligosaccharides which have been developed in the past few years to use as physiologically functional foods consist of proliferation of bifidobacteria and reduction of detrimental bacteria, diminution of toxic metabolites, anti-cancer effect and protection of liver function. These biologically active compounds in food legumes also have immense potential in biomedical application. On the other hand, phytochemicals have adverse effects as they limit the digestibility of proteins and carbohydrates or reduce the bioavailability of certain nutrients, interfere with normal growth, reproduction and flatulence production. Moreover, phytoestrogens have been linked with infertility problems. The synergistic or antagonistic effects of mixtures of these phytochemicals from food legumes, their interaction with other components of the diet and the mechanism of their action have remained a challenge with regard to understanding the role of phytochemicals in health and diseases. Current researches in phytochemicals are exploring various potentials and utilization in foods and drugs which could be used as frontline defences against numerous life threatening diseases including HIV/AIDS. Because of the potential health benefits of phytochemicals in food legumes, it is probably inappropriate to refer to these substances as natural toxins. The time has come for us to re-evaluate their presence in our diet. Their mitigating effects and the mechanism of their action need to be further addressed if we are to understand the role of phytochemicals in health and diseases.