|Bridging the nutritional divide 2|
Meeting the Challenges
A food-based approach to nutrition security would involve the following steps.
Food availability: This is a function of both home production and imports. In many developing nations, the gap between potential and present yields is high in most farming systems, even with the technologies available off the shelf. High priority should hence be accorded to bridging the productivity gap through a mutually reinforcing blend of technologies, services and public policies. Also, mainstreaming the nutritional dimension in the design of cropping and farming systems is essential. There is no time to relax on the food production front. The present global surplus of food grains is the result of inadequate consumption on the part of the poor, and should not be mistaken as a sign of over-production. Developing nations should aim to achieve revolutions in five areas to sustain and expand the gains already achieved. These are:
1. Productivity Revolution: The scope is great since average yields are still low in most cropping and farming systems. However, the production techniques should be environmentally sustainable, so that high yields can be obtained in perpetuity.
2. quality revolution: This can be achieved through greater attention to post-harvest technologies and bio-processing, as well as to sanitary and phytosanitary measures and Codex Alimentarius standards.
3. income and employment revolution: This will call for integrated attention being directed at on-farm and non-farm livelihoods and at farming systems intensification, diversification and value addition. Post-harvest processing offers scope for generating additional livelihoods through micro-enterprises supported by micro-credit.
4. small farm management revolution: Institutional structures which will confer upon farm families with small holdings the advantages of scale at both the production and post-harvest phases of agriculture are urgently needed. For example, thanks to the cooperative method of organisation of milk processing and marketing, India now occupies the first position in the world in milk production. Strategic partnerships with the private sector will help farmers’ organisations to have access to assured and remunerative marketing opportunities.
In relation to factors of production, water is likely to become the key constraint during this century. Hence, every effort should be made to enhance productivity and income for every drop of water.
5. enlarging the food basket: During the last century, there has been a rapid decline in the number of crops contributing to global food security. In the past, local communities depended upon a wide range of crops for their food and health security. It is important that we revive the old dietary traditions. Particular attention needs to be paid to leafy vegetables, which are rich in micronutrients (Table 7).
Food access: Inadequate livelihood opportunities in rural areas result in household nutrition insecurity. Today, India has over 65 million tonnes of wheat and rice in government godowns; yet poverty-induced hunger affects over 200 million persons. Macro-economic policies, at the national and global level, should be conducive to fostering job-led economic growth based on micro-enterprises supported by micro-credit. Where poverty is pervasive, suitable measures to provide the needed entitlement to food should be introduced.
Food absorption: Lack of access to clean drinking water, as well as poor environmental hygiene and health infrastructure, lead to a poor assimilation of the food consumed. Nutrition security cannot be achieved without environmental hygiene, primary healthcare and clean drinking water security. Culinary habits also need careful evaluation. Some methods of cooking may lead to the loss of vital nutrients.
Transient hunger: Ferro-Luzzi et al (1994) have carried out a detailed study of seasonal cycling in body weights related to changes in weather. Any strategy for nutrition security should provide for steps to meet such transient hunger. Almost 25 years ago, The Indian state of Maharashtra introduced an Employment Guarantee Scheme to help the poor earn their daily bread during seasons when opportunities for wage employment are low. Similarly, there is a need for mainstreaming considerations of gender, age and occupation in the national nutrition strategy.
Fortification and synergy among dietary component: Our understanding of low-cost and high-synergy nutritional systems is growing. Fortification of flour with folic acid and genetic enrichment of staple grains with beta-carotene and iron are now receiving attention.
Knowledge relating to the metabolic interrelationships among micronutrients is also growing, as for example among Vitamin A, protein, zinc, iron, folic acid and Vitamin C. However, in the absence of dietary interventions, iron-folate supplementation often fails to bring about a complete correction of anaemia. Hence, the attack on under-nutrition induced hunger and micronutrients deficiency-caused hidden hunger should be an integrated one. Such an integrated strategy should accord concurrent attention to food availability, access and absorption. In addition, there should be provisions in the strategy for overcoming seasonal or transient under-nutrition caused by loss of opportunities for livelihood during seasons of drought, floods or other natural calamities.
Genetic enrichment of nutritional quality: While the problems relating to the food and environmental safety aspects of genetically modified foods are yet to be fully resolved, there is little doubt that an integrated approach involving Mendelian and molecular breeding is likely to make a food-based approach to nutrition even more effective in the future. The quantity and quality of proteins, carbohydrates, fats, vitamins and minerals can all be improved now. The scope for the genetic enhancement of nutritional quality will be evident from the following examples:
n Quality protein maize (QPM). Scientists have long had an interest in improving maize protein quality. Quality protein maize (QPM) refers to enhanced levels of the two ‘essential’ amino acids, lysine and tryptophan, in the endosperm protein. Using Mendelian breeding methodologies supported by rapid chemical analysis of a large number of samples, scientists led by S. Vasal and Evangelina Villegas of the International Maize and Wheat Research Centre (CIMMYT) in Mexico were able to slowly accumulate modifier genes to convert the original soft opaque-2-endosperm into the vitreous hard endosperm type (Vasal et al, 1984). This conversion took nearly three decades. These remarkable new varieties look and taste like normal maize but the nutritive value of their protein is nearly equivalent to cow’s milk. They also produce yields as much as 10 per cent higher than the best local hybrid maize varieties and are more tolerant of biotic and abiotic stresses. QPM, which is a product of Mendelian breeding, promises improved nutritional value and cost savings for a wide array of products ranging from infant food to corn chips and feed for non-ruminant livestock. The impact of this breakthrough is likely to be felt throughout the food industry and has great promise in the developing world, both for human and animal nutrition.
n Beta-carotene rich rice. A promising development in the field of genetic engineering is the success in breeding a nutritionally enriched rice variety now popularly referred to as ‘golden rice’. This genetically modified rice contains genes that produce high levels of beta-carotene and related compounds, which are converted in the human body into crucially needed Vitamin A. Vitamin A deficiency (VAD) causes more than a million childhood deaths each year and is the single most important cause of blindness among children in developing countries. Rice plants do produce cartenoid compounds (that our body converts into Vitamin A) but only in the green parts of the plant, not in the part of the grain normally eaten. Dr Ingo Potrykus and Dr Peter Beyer of the Swiss Federal Institute of Technology inserted genes from a daffodil (Narcissus pseudonarcissus) and a bacterium (Erwinia uvedovora) into rice plants to produce the modified grain, which has sufficient Beta-carotene to meet total Vitamin A requirements in a typical Asian diet (Ye et al, 2000). If golden rice, which is still in the laboratory stage, becomes a success in the field, it will help to strengthen the food-based approach to nutrition security.
n Iron enrichment. Iron-deficiency anaemia is the most widespread nutrient deficiency in the world, affecting an estimated 2 billion people worldwide. Between 40 and 50 per cent of children under the age of five in the developing countries are iron-deficient and iron deficiency accounts for up to 20 per cent of all maternal deaths. It also impairs immunity and reduces the physical and mental capacities of people of all ages. In short, iron deficiency is a major public health problem worldwide with enormous social and economic costs. Rice fortified with iron was created through the introduction of proteins from kidney beans (Phaseolus vulgaris) by the same researchers at the Swiss Federal Institute of Technology (Lucca et al, 2000). It is reported that the iron content increased two-fold in the modified crop, which is now in the testing stage. Japanese scientists have also succeeded in enriching the rice grain with iron. The International Rice Research Institute (IRRI) has developed rice-breeding lines high in iron and zinc using traditional plant breeding techniques. This rice is currently being tested by novitiates at a convent in the Philippines to see how well the nutrients are absorbed in the human body.
n Designer potatoes. Advances in plant tissue culture techniques and gene transfer technology have opened up possibilities for modifying the amino acid contents of plants. The potato, which is the most important non-cereal food crop, ranks fourth in terms of total global food production. Besides, it is used as animal feed and as raw material for the manufacture of starch, alcohol and other food products. This crop was genetically modified using the seed albumin gene Ama1 from Amaranthus hypochondriacus by researchers of Jawaharlal Nehru University (JNU), New Delhi, India (Chakraborty et al, 2000). The Ama1 protein is non-allergenic and rich in all essential amino acids. Its composition corresponds well with WHO standards for optimal human nutrition (Raina and Datta, 1992). The JNU team was able to use a seed albumin gene with a well-balanced amino acid composition as a donor protein to developing a transgenic potato. The genetic enrichment of protein quantity and quality in potatoes can make a significant contribution to child and adult nutrition, since mashed potatoes can be fed to young children.
The above are a few examples of the work in progress in improving, through conventional and molecular breeding techniques, the quantity and quality of protein in important food crops. Consumer confidence based on an appreciation of the scientific evidence and the regulatory checks and balances will ultimately decide whether or not genetically modified foods (GMOs) will make a significant contribution to feeding the 8 billion people who are likely to inhabit our planet by 2020. Marker-aided selection and transgenic approaches are two powerful tools to accelerate plant breeding to produce crop varieties with improved nutritional traits and qualities. An intelligent integration of Mendelian and molecular breeding techniques will help to enhance the nutritive value of staples. By integrating pre-breeding in laboratories with participatory breeding in farmer’s fields, it will be possible to breed location-specific varieties and maintain genetic diversity in crop fields.
M.S. Swaminathan, a founding father of the Green Revolution in India, worked to develop the nation’s food security as Secretary for Agriculture. He has also been Director General of the Indian Council of Agricultural Research and the International Rice Research Institute, Independent Chairman of the FAO Council, and President of the International Union for the Conservation of Nature and Natural Resources. He is a member of the Royal Society, the US National Academy of Sciences, the Russian Academy and the Italian and Chinese Academies. His honours include the World Food Prize, UNEP’s Sasakawa Award and the Tyler and Honda Prizes. He lives in Chennai, where he heads the Centre for Sustainable Agricultural and Rural Developmen