Nutrient Requirements and Recommended Dietary Allowances Estimated Average Requirements

Foreword The formulation of the recommended dietary allowances (RDAs) for Indians has a long and distinguished history. The RDA of energy for Indians was first proposed by the Nutrition Advisory Committee (NAC) of the Indian Research Fund Association (IRFA) [now Indian Council of Medical Research (lCMR)] in 1944. These recommendations were based on the proposals of the Health Committee of the League of Nations made in 1935 but adapted to the lower body weights of all dial. adduct, The 1944 recommendations for energy for Indians were revised subsequently by the NAC of the ICMR in 1958 in the wake of report by Food and Agriculture Organization (FAO) on energy and protein. Subsequently, in 1968 and 1978 the ICMR committee revised the requirements for all nutrients except energy. Considerable additional information and newer statistical approaches for deriving energy requirements were generated and the FAO/WHO/UNU revised approaches in 1985 and again in 2004.

In 1989, the ICMR Expert Group adopted the procedure of 1985 FAO/WHO/UNU Expert Consultations and revised the Indian RDA. The ICMR 2010 committee RDA recommendations further revised and upgraded the RDAs for Indians based on the international data provided by FAO/WHO/UNU expert committee and based on weight and height collected across 10 states by NIN - NNMB rural data.

The present committee took the latest statistical approaches to derive the requirements through definitions of their distributions, such that the estimated average requirement (EAR) could be defined for population requirements, and the upper 97.5th percentile of the distribution could be used to defame the individuals' requirements to place them at low risk of a deficient intake. In addition, since several foods are now being fortified with nutrients, the tolerable upper limits of intake of nutrients were also defined. The need for these new nutrient requirements has been because dietary patterns have changed with economic and nutrition transition occurring during the last decade. The double burden of malnutrition is evident in India. Nutrient requirements have to be reviewed with respect to recent data on energy expenditure, protein metabolism and in case of minerals and vitamins- data on losses and absorption need to be explored to derive EAR and RDA.

The process for generating this report was similar to the earlier recommendations. This draft Report was circulated to the Expert Group members and external Resource Persons well in advance of the meeting for them to go through and make specific comments on the requirements. Each nutrient was considered one by one at the expert group meeting for discussing the specific comments of the members of the expert group and resource persons. The presence of Dr. Maharaj Kishan Bhan, who passed away earlier this year, as Chair of this expert committee was invaluable.

He had been a pillar of support to the ICMR-National Institute of Nutrition, serving for 10 years as the Chair of its Scientific Advisory Committee. The ICMR 2020 Committee wishes to place on record its deep appreciation for his guidance and expertise.

Introduction The RDA book defines nutrient distribution and requirements for normal individuals of all age groups of Indian population. A fundamental part of defining nutrient requirements is that the requirement is not the same in all people. It can vary considerably in healthy individuals. In order to derive a single value for the requirement, two features of this distribution of requirements are used. First, the median of this distribution is called the estimated average requirement (EAR). The EAR is the nutrient requirement used in public health nutrition, to evaluate the nutrient intakes of a population. Second, the 97.5th percentile of the distribution is called the Recommended Daily Allowance. The RDA is for healthy individuals and may be prescribed to satisfy the nutritional needs of specific nutrients in a specific life stage and gender group and ensures that there is a very small risk of the nutrient intake being inadequate. With the RDA, there is also the risk of excess intake, since each individual may not actually require that much. There is no need to consume higher doses on regular basis or for prolonged period without supervision. Therefore, readers of this book will note that there has been a shift from the previous edition, and two distinct nutrient requirements are now presented: the EAR and RDA. In addition, nutrients are also toxic when ingested at very high doses.

This has resulted in the definition of the Tolerable Upper Limit of Intake (TUL). Intake of nutrients more than the TUL invites the risk of toxicity. It cannot be overstated that when assessing the health and nutritional status of the population, EAR is recommended as the unit of requirement.

In India, the first attempt to define nutrient requirements and desirable dietary intakes of nutrients for Indians to maintain good health was made by the nutrition Advisory Committee of the Indian Research Fund Association [Now Indian Council of Medical Research (ICMR)] in 1944'. This followed the recommendations made by the Technical Committee of the Health Committee, League of Nations in 19362, Food and Nutrition Board of the National Research Council, USA, 19443 and Report of the Committee of Nutrition, British Medical Association 19334. During this period, requirements and allowances of only energy, protein, iron, calcium, vitamin A, thiamine, riboflavin, ascorbic acid and vitamin D for Indians were considered. Considering these recommendations, a typical balanced diet based on habitual Indian dietary habits was formulated to provide all the nutrients for a normal adult reference man of 55 kg and a normal adult reference woman of 45 kg body weights. This was used to demonstrate that the diet then consumed by Indians, particularly by the poor, was deficient in several nutrients and could be improved by inclusion of some protective foods.

THE CURRE T NUTRITION SCENARIO IN INDIA

India is in developmental transition and is facing the dual burden of malnutrition. The pre- transition diseases like under nutrition and infectious diseases as well as post-transition, lifestyle- related degenerative diseases such as obesity, diabetes, hypertension, cardiovascular diseases and cancers are wide-spread in India. The last National Family Health Survey (NFHS) - 4 indicates a slight decline in under nutrition, with a prevalence of stunting as 38.4% and wasting as 21.5%6. Simultaneously, the burden of over nutrition has increased to about 20% in adult men and women.

Severe clinical forms of Protein Energy Malnutrition (PEM) - kwashiorkor and miasmas have become very rare. Over 50% women (particularly pregnant women) and children suffer from iron deficiency anemia (IDA), aggravated by helminthes infections. Though blindness due to vitamin A deficiency has become rare, a survey conducted by National Nutrition Monitoring Bureau (NNMB) shows that milder grades of deficiency as judged by clinical signs like night blindness and Bigot’s spots and low serum vitamin A levels, are common? Deficiencies of other micronutrients like some B-complex vitamins particularly riboflavin, folic acid and perhaps vitamin B 12 are also common.

Rickets has become rare, but recent studies from North and South India show that vitamin D deficiency as judged by serum levels of 25-hydroxy vitamin D exists in adults. This, besides low intake of calcium, may be responsible for the high prevalence of osteoporosis particularly in women.

The problem of severe forms offloading Deficiency Disorders (IDD) (an environmental problem) has been considerably reduced after universalization of Iodized salt. However due to improper implementation, milder forms of IDD persist in many districts. For every frank case of nutrition deficiency, there are dozens of others who suffer from sub-clinical malnutrition.

REVISIO OF HUMAN NUTRIE T Requirements

In the wake of reports by the Food and Agriculture Organization (FAO) on calorie=? and protein'? in 1950 and 1957 respectively, an attempt was made by the ICMR in 1958 through its Nutrition Advisory Committee (NAC) to revise protein and calorie requirements of Indians, based on data available at that time II. In 1968, the requirements of all nutrients except energy were reviewed by an Expert Committee constituted by ICMRI2. In 1978, the Recommended Dietary Allowances (RDA) for Indians was again reviewed by another Expert Group of the ICMR and RDAs of several nutrients were revised 13. In the recommendations made by the ICMR Expert Group in 1968 and 1978, a wide range of balanced diets for different age and sex groups were formulated which, if consumed, could ensure a daily intake of all nutrients at the recommended levels. The recommendations on human protein and energy requirements were again revised by a Joint Expert Group of F AO, WHO and United Nations University (UNU) in 198514. In arriving at human energy requirement, this International Expert Group followed an entirely new set of guidelines. Based on the new international guidelines, the ICMR 1989 revised the RDA for Indians". However, no substantial changes were made in the RDAs for protein, B-complex vitamin, iron and calcium. Also, no definitive recommendations were made for trace elements. Over the years, with the advancement in the data on various nutrients among Indians, the ICMR 2010 committee made changes to the RDAs 17. The ICMR 2010 committee recommendations were developed based on the available data in India and international data provided by FAO/WHO/UNU expert committee.

Energy allowances for Indians, which were recommended in 1958, had not been revised till 1988. In 1988, an Expert Group was constituted by the ICMR. The previous Expert committees of ICMR considered the updated accumulated data on Indians after 197314 while following the new guidelines of the Joint FAO/WHO/UNU Consultative Group of 198515 to define the energy and protein requirements of Indians. The Expert Group also defined the requirement of other nutrients like fat, vitamin D and vitamin A. However, no changes were made in the recommendations on the requirement of B-complex vitamins, iron and calcium. Further, recommendations on several additional nutrients such as carbohydrate, dietary fiber, water, phosphorus, vitamin E and vitamin K or dietary factors not considered by the earlier ICMR Expert Committees and made provisional recommendations on their desirable intakes to maintain good health. Dietary fat requirements were examined in greater detail and recommendations regarding the requirement in terms of invisible and visible fats were made"'. The reference body weights of normal healthy adult man, woman and children were also altered based on the body weight data on healthy normal adults and children obtained by National Institute of Nutrition (NIN).

**Contents and Sample Pages**