| Food designer: Kalidas Shetty at Bose Institute (Pic by Sanat K. Sinha)
You are what your ancestors ate. And those ancestors would pick and choose fruits, nuts, seeds and the occasional helping of meat or fish. Most of the ancient food items are not just nutrients but can combat chronic diseases like arthritis, cancer, heart disease, diabetes and hypertension. 'Traditional diets are rich in phytochemicals (plant-chemicals) that defend us against reactive oxygen species produced in the body in course of metabolism,' said Prof. Kalidas Shetty while addressing a symposium at the Bose Institute last Monday. Shetty is a food biotechnologist at University of Massachusetts (UMass) at Amherst, US. 'Which is why we call these nutrients nutraceuticals.'
Most chronic diseases are the handiwork of damaging reactive oxygen which interact with key cellular molecules such as proteins, lipids and DNA. The plant chemicals act as antioxidants protecting the tissues of our body. 'Especially effective are phenolic antioxidants found in fruits (grapes, berries etc.), legumes (beans, lentils), herbs (spearmint, oregano) and spices (cumin, turmeric and cinnamon).'
The nutraceuticals inspire scientists like Shetty to design food appropriate for modern humans whose diet has shifted from what their ancestors ate. Not only do we now eat less nutritious food, we go on piling loads of calories we are unable to utilise. 'More and more people are getting over-nourished in the new world order,' said Shetty. 'This is happening all over the world ' even in countries like Nigeria or Kenya normally associated with undernutrition.' Naturally, obesity-related diseases ' diabetes, hypertension and heart diseases ' are on the rise.
'You can't make people change their diet or lifestyle, so why don't you bring about suitable modification in food,' said Shetty. His lab at U Mass is trying to enhance food in such a way that it doesn't make you put on weight or usher in diabetes. In addition, it can restrict adding up calories and also fight a number of chronic illnesses. 'For instance, we are in the process of designing a rice which will have resistant starch that can't be broken down easily,' said he. Which means even if you go on eating loads of the modified rice you won't be at risk of either obesity or diabetes. The engineered rice can also be coaxed to contain nutrients that we normally don't get in our usual diet.
In an interview after his talk, Shetty cited the case of the famous 'golden rice', innovated by Swiss biotechnologists, as an example of a foodgrain incorporated with a vital nutrient like beta-carotene (a precursor of vitamin A). 'Although golden rice demonstrates how food technology can help ameliorate rampant blindness brought about by vitamin A deficiency it's far from being the ideal food grain,' he commented.
The rice looks golden-yellow, alienating a large number of people used to white rice. It isn't as tasty the as white grains. Buyers are unlikely to switch to a new staple for vitamin A which is found in cheaper sources like fruits and vegetables. 'Above all, any of the novel food has to be environment-friendly or adapted to the local environs,' Shetty said.
He and his colleagues at UMass have decided to learn from the mistakes. The method of genetic engineering adopted by them coaxes modified variety food to produce calories or energy in the body through an alternate energy-producing pathway called pentose-phosphate pathway (PPP). Unlike the usual adenosine triphosphate pathway (ATP), in PPP food is metabolised in cells involving a basic building block called proline to stimulate antioxidant response in the body.
'The primary goal is preventive management of damaging oxidation-linked chronic diseases caused in the course of normal energy metabolism,' said Shetty 'Our model for the novel food grain are phenolics found in certain fruits, legumes, herbs and vegetables.'
For the experimental engineering of nutraceuticals Shetty has chosen phenolics like fava or velvette bean (Vicia fava) to fight oxidative damages that cause Parkinson's, moong bean (Vigna radiata) to combat radiation-linked damages, spearmints or ocimum (tulsi) to fight cancer and soybean to combat hormone disorders in women. Surprisingly, many of these model plant chemicals find mention in traditional ayurvedic medicine. For instance, the fava beans have been routinely advised to treat geriatric problems by ayurvedic practitioners.