Health and nutritional studies among Shompens

The Shompens, one of the two mongloloid tribes of Andaman and Nicobar Islands, inhabit the Great Nicobar, the southern most island of Andaman and Nicobar archipelago. There are two main groups among them, each occupying separate geographical territories. One group occupies areas near the east coast of the island and the other towards the west coast. They are semi-noimadic forest dwellers, and depend mainly on forest produce for their needs. Besides what they gather and hunt from the jungles, they maintain small pandanas gardens, rear domestic pigs and do fishing. They consume yam, honey, eggs and wild fruits gathered from the forests, sea food like fish, turtles, crab, octopus and mollusks. Rice, pulses, sugar etc. which they receive from Andaman and Nicobar Administration also form part of their diet.

Fig 1. Change in the population of Shomens during 1901—1991

A study was undertaken to assess to nutritional status and morbidity pattern among the Shompens. The estimated population of Shompens over the last 100 years is shown in the fig. 1. The big fluctuations in their population between consecutive census years from 1951-1971 indicate the inaccuracy of the estimates during this period. Considering their population during the pre independence period, there is decline in their numbers from about 350 in 1901 to 157 in 1991.

Fig 2. Age structure of Shompens

Age and sex distribution of 86 contacted Shompens during the study is shown in the fig. 2.. It is observed that children aged 14 years and less constitute 25.58%, persons in the age group 15 - 44 years 56.97% and those aged 45 years and above 17.44%. These figures are different from figures of 39.7%, 49% and 11.3% respectively for A &N as a whole at 5% level (c2= 8.31;  df=2;  p=0.0157). Children under five years of age constitute 13.95% of the population. The oldest Shompen man was 65 years old and the oldest woman 50 years.

There were 18 females and 68 males among the group of contacted Shompens giving a sex ratio of 264.7. Since only men visit the Shompen Hut Complex, the sex ratio of 264.7 calculated from all the contacted Shompens would be less than the actual sex ratio. If those Shompens contacted at the Shompen Hut Complex were excluded from the calculation, the sex ratio becomes 486.5 females per 1000 males.

Nine of the 40 babies born alive to the 12 ever married women in the community died before completing their first year of life, giving an over all Infant Mortality Rate of 225/1000 live births during the past 30 years. Total under five mortality rate (17/40) during the past 30 years is 425/1000 live births. As in the case of other primitive tribes of the islands, the cause of the decline in the population of shompens appears to be the low survival rate of the children. These figures indicate that the cause of the decline in their population strength is mainly due to high child mortality rate particularly among female children rather than due to lower reproduction rates.

Since their cooking and eating habits are not well organised, it was not possible to collect accurate information about the types and quantity of food items they consume. Follow up was also not possible because of their erratic eating habits. Any inference drawn based on consumption of food on a single day will be incorrect due to the wide variation in the consumption of food from day to day.

Even if information about consumption of raw food could be collected with some accuracy, interpretation of the data would be extremely difficult as the bulk of Shompen diet is constituted by non-conventional foods, whose nutritive values are not known.

The mean values of Body Mass Index (BMI) for adult Shompens of both the sexes, except for females above 50 years, were higher compared to that of rural Indians in the respective age groups (table 1). . Only 2 out of 48 adults (4.2%) show chronic energy deficiency.    Three adults (6.2%) were found to be obese of whom two were males and one female. 43 adults (89.6%) had BMI within normal range. As a whole, the Shompen adults seem to have good nutritional status with the mean BMI 22.49 for both the sexes combined. The mean BMI for adult males was 22.76 and for female 21.45.

Fig 3. Distribution of Shompen under-fives by SD score of weight for age

(NCHS reference data)

Fig 4. Distribution of Shompen children aged less than 10 years by SD score of weight for age

As compared to the overall satisfactory nutritional status of adult Shompens, majority of the children under five years of age (66.67%) had low weight for height compared with the NCHS reference data (fig. 3 & 4). More than 58% of the under-fives had weight for height 2SD less than NCHS reference data for their age and sex (fig. 38). Malnutrition is not common among older children as only one girl aged about 8 years had weight for height 2SD less than NCHS reference data.

 A comparison of the anthropometric measurements of adult Shompens taken during 1989 and 1998 is shown in table 15. All the anthropometric indices of males deteriorated during this period while in females these have remained more or less the same except for fat fold thickness, which decreased by 4.9 mm. Clinical signs of anaemia were present in 39 (45.3%) individuals. Anaemia prevalence was found to be higher in females than in males (66.7% vs 39.7%). Conjunctival xerosis suggesting Vit. A deficiency was found in two children. However, no case of Bitot's spots was seen. Other nutritional deficiency signs observed were angular stomatitis in three children and goitre in one adult female. All the children examined had moderate to severe degree of anaemia. Moderate to severe degree of anaemia was also found more common among women, whereas all the anaemic men had mild to moderate degree of anaemia. Prevalence of anaemia was also higher among females than in males (93.3% vs 82.5%).