Obesity In The Indian Urban 'Middle Class'

C. Gopalan

developments is the rising prevalenceof overweight and obesity in the middleclass. Our efforts must now be di­rected to control this basic problemwhich has far-reaching public healthimplications.

By the turn of the century nearly35 per cent of India's population willbe living in urban areas. The corre­sponding figure for 1950 was no morethan 16 per cent. Steady urban mi­gration has been an important fea­ture of the ongoing developmentaltransition not just in India, but in alldeveloping countries as well. Thus,Asia's urban population is expectedto exceed 1,242 million by 2000 AD,more than a five-fold increase from226 million in 1950. This process ofurbanisation is expected to continuein the decades to follow.

Urbanisation involves changesin occupation patterns, life-styles, familystructures and value systems. Thesechanges are reflected in changes indietary practices and in the levels ofphysical activity. In the urban popu­lation of India, refined wheat and ricehave virtually displaced coarse grainsand millets as the staple cereal, re­sulting in a substantial reduction infibre content in the diet and, possi­bly, also the content of micronutri­ents such as vitamin B-complex, zincand chromium, etc. As the popula­tion ascends the socio-economic scale,cereal intake declines and intakes of

sugar and fats generally increase.Convenience foods and fast foodsfind increasing acceptance, especiallyin the context of globalisation.

While the rural population is mainlyengaged in agricultural occupationsinvolving manual labour and a fairlyhigh level of physical activity, urbanoccupations (except those of someof the urban slum dwellers) are gen-

erally of the 'skilled' and 'semi-skilled'categories that tend to favour seden­tary life-styles. Bicycles, generally usedin earlier years by the staff for com­muting from their homes to offices,are now being rapidly displaced bymotorbikes and cars - not only inIndia but in China and other Asiancities as well. Thus, it has been re­ported that nearly 10,000 automo­biles are being added to the automo­bile fleet in Delhi every month! Apartfrom cutting down on physical exer­cise, this change is contributing tosignificant aggravation of the prob­lem of air pollution in the cities.

While a third of India's popula­tion still falls below the poverty line,there has been a steady growth of therelatively affluent urban middle class,now estimated to number over 200million. A good proportion of this middleclass is constituted by those whohave achieved affluence within a life­time. This number is expected to in­crease in the coming decades.

The changes in dietary prac­tices, physical activity levels and life­styles associated with rising afflu­ence induced by developmental tran­sition mentioned above contribute tothe increasing prevalence of over­weight/obesity. Earlier issues of thisBulletin had drawn attention to thedisturbing escalations in the preva­lence of chronic degenerative dis­eases1 - especially coronory heartdisease, diabetes (NIDDM) and thechanging profile of cancers in theurban populations. The underlyingfeature common to these disturbing

THE NFl STUDY

The Nutrition Foundation of In­

dia has just completed a study of theprevalence of obesity in urban Delhi.The study was supported by the In­dian Council of Medical Research(ICMR) and was carried out with theactive cooperation and participationof Dr S. Padmavati from the NationalHeart Institute of Delhi. Detailed sta­tistical analysis of the data was car­ried out by Dr Visweswara Rao of theNational Institute of Nutrition (NIN).The results of the study are beingpublished separately in a ScientificReport of the Foundation. In this pa­per, some salient observations emerg­ing from the study are brieflydiscussed.

In view of wide disparities withrespect to diet, physical activity andlife-styles in general, as between the'middle class' and the poor in India,'average' figures of prevalence ofobesity have no meaning and do notprovide any leads for corrective ac­tion. The study, therefore, made anattempt to capture fairly representa­tive segments of the middle class

CONTENTS

• Obesity In The IndianUrban 'Middle Class'- C. Gopalan

• Fruit And VegetableProduction In India 5- G.L. Kaul

TABLE 1Percentage prevalence of overweight(BMI 25 +) in urban adults bysocia-economic status

Economic status

Prevalence %

Males

Females

Middle Class 1. High

32.2a50.0'

(118)

(142)

2. Middle

16.2b30.3b

(142)

(33)

3. Low

7.0e27.8b

(86)

(18)

Slum (poor)

1.0d4.0e

(218)

(250)

a,b,e,d p <0.05

( ) sample sizeSex differences are significant in all(p<0.05)Source: NFl studies, 1997

and of the poor in urban Delhi. It wascarried out in two locations: 1. A largeoffice establishment employing sev­eral hundred people, drawn largelyfrom what may be termed the 'middleclass' consisting of officers (high-in­come), clerks (middle income) andpeons/attendants (low-income); and2. A slum in Delhi inhabited mostly bypoor, unorganised labour, the slumbeing typical of numerous others inDelhi and its environs.

The investigations included

anthropometery, blood pressure re­cordings, assessment of diets andlevels of physical activity. In a sub­sample of (1) above, ECGs and esti­mations of serum lipid profile, seruminsulin and sugar levels were alsocarried out. Internationally acceptedyardsticks for the assessment of theprevalence of overweight, obesity andabdominal obesity were employed asfollows: Body Mass Index (BMI): Weight(kgs)/HeighF (metres); Overweight:BMI between 25 and 30; Obesity:BMI>30; Abdominal Obesity: Waist!Hip Circumference (WHR) >1.0 inmales and >0,85 in females.

PREVALENCE OF OVERWEIGHT

The striking difference in theprevalence of overweight between themiddle class and the slum dwellers isobvious from the data in Table 1 whichclearly show how, with the ascent inthe socio-economic scale, the over­weight problem worsens. Thus, asagainst the prevalence rate of over­weight of 1 per cent for males and 4per cent for females in the slums, thecorresponding figures for the high­income group among the middle classwere 32.2 per cent and 50 per cent.More females than males have beenfound to be overweight in all agegroups in both locations.

Table 2 presents the distribu­tion of all subjects of the middle classaccording to the BMI in two age groups.It will be seen that the prevalence ofoverweight/obesity is higher in theage group >40 years. The preva-

lence of obesity (BMI>30) is about 3per cent in males and about 14 percent in females above 40 years.

The prevalence rates of obesityobserved in the NFl study in urbanDelhi are generally in line with obser­vations reported by Visweswara Raoet a/2, except that the rates among thehigh-income group in the NFl studyare somewhat higher. Thus, VisweswaraRao et al had reported a prevalencerate of 23.9 per cent in urban malesand 36.3 per cent in urban females ofthe high socio-economic group ascompared to 0.8 per cent in ruralmales and 2.2 per cent in rural fe­males. The NNMB report of 19963,

covering nine Indian states, reporteda prevalence rate of overweight of 3.6per cent in rural males and 6.6 percent in rural females. These figuresare somewhat higher than those fig­ures reported by Visweswara Rao,but they are still far less than thoseobserved for any section of the urbanmiddle class.

The prevalence of overweight!obesity in the urban middle class asrevealed from the data of the NFlstudy is less than what has beenreported for Europe' or the USA'- Thus,in the UK, 50 per cent men have beenreported to be overweight as against32 per cent in the high Indian socio­eonomic group investigated here; 15per cent of men and 16.5 per cent ofwomen in Europe have been reportedto be obese (BMI>30) as against 3per cent of males and 14 per cent offemales above 40 years in India. The

TABLE 2BMI and WHR levels in two age groupsAge Group

8MIWHR

(Vrs)

NumberLess than 1818.0 - 24.9925.0 - 29.9930 andLess than1/0.85 andabove

1/0.85above

M

FMFMFM FMFMFMF

<40 yrs

95882108655709 19-0479591629

% Distribution

27.4545.622.109.0968.8464.499.4721.60-4.5483.1567.0416.8532.96

40-60 yrs

251105250216740514808151463810567

% Distribution

72.5554.49.961.9066.5338.0920.3145.713.1914.2858.1636.1941.8463.81

Total

34619346102329760 6708192259712196

(17.3%)

(34.8%)(2.31%)(9.84%) (49.7%)(34.9%)

TABLE 6Mean values of parameters by tertile values of BMI and WHRParameter

BMI WHR

Males

FemalesMalesFemales

I

III IIII IIII IIII

Systolic BP(mmHg)

123.1133.9***119.4130.1**122.7134.2***120.0132.6***

Diastolic BP(mmHg)

78.184.9***77.982.3*77.785.5***79.081.8

Triglycerides(mg/dl)

118.2166.3**99.0146.9106.6173.2**103.8146.6

Cholesterol(mg/dl)

181.7209.7*191.9218.9186.2217.6*180.9213.9

LDL Chof.(mg/dl)

-- 148.2157.0-- 132.3152.3

VLDL(mg/dl)

-- 21.132.4-- 28.729.8

HDL Chof.(mg/dl)

35.034.742.340.335.533.643.337.7

Chof. Ratio

5.36.2 4.85.7 7.66.44.45.7

Blood Sugar(mg/dl)

95.4105.698.9105.394.6104.7113.6100.6

Insulin

22.324.021.223.024.024.529.122.1

* Note: Those marked with stars are only significant.* P<0.05; ** P<0.01; *** P<0.001I and III refer to the respective tertiles

TABLE 3Percentage prevalence of abdominaladiposity in adults by socio-economicstatus and sexEconomic

Prevalence %status

Males

Females

Middle Class 1. High39.0'50.0'

(118)(142)

2. Middle28.9b48.5'

(142)(33)

3. Low16.3°50.0'

(86)(18)

Slum (poor)3.7d6.4b

(218)(250)

',b,c,d p <0.05

( ) Sample sizeSexdifferencesaresignificant inall (p<0.05)Source: NFl studies, 1997

corresponding figures for obesity inthe USA are 19.7 per cent and 24.7per cent.

The relatively low figures foroverweight/obesity in the Indian ur­ban middle class, however, shouldnot lead to complacence. The spe­cial features pertaining to the Indianpopulation have to be taken into ac­count in drawing conclusions basedon international comparisons of overallprevalence rates of obesity. Thedistribution of excessive fat in thebody may be an important factor whichmay determine the implication of agiven order of obesity. Abdominaladipocytes are metabolically differ­ent from those in other locations andabdominal adiposity may carry a moresinister significance than generalobesity. Indeed, the possibility thatIndians may be genetically more proneto develop abdominal adiposity needsto be considered. Furthermore, the

TABLE 4% of subjects with high WHR(abdominal obesity) by grades of BMI

Details

Grades% (with highof BMI

WHR)

Males

Females

(>1.0)

(>0.85)

Under- nourished

<18.51.81.75

Normal

18.5-2517.820.0

Overweight /obese

>2568.158.0

TABLE 5Prevalence rates (percentage) of highBP by grades of BMI and WHRBMI

WHR*% with high BP

Males

Females

<18.5

Low1.90.0High

0.00.018.5-25.0

Low9.81.7

High

12.510.8>25

Low15.05.4High

31.115.6

* Note: Those having systolic and diastolicblood pressure of more than 140 and 85respectively are taken as having high bloodpressureHigh: > 1.0 in males and >0.85 in femalesLow:<1.0 males and <0.85 in females

possibility of some sections of theIndian population being more sus­ceptible to the deleterious effects ofoverweight because of genetic pre­disposition or because of undernutri­tion (including intra-uterine) in earlylife needs to be kept in mind, If this is

3

the case, the yardsticks for identifi­cation of overweight (BMI>25) andobesity (BMI >30) may need revisionin the case of Indian (and Asian)subjects.

ABDOMINAL OBESITY

The prevalence of abdominal adi­posity in the subjects of the NFl study(Tables 2 and 3) was higher than theprevalence of overweight/obesity(BMI>25).

When all subjects of the middleclass were considered together (seeTable 2), abdominal adiposity wasfound in 34.9 per cent of males and49.7 per cent of females; the figuresfor general overweight (BMI>25) were19.6 per cent in males and 44.5 percent in females. Abdominal obesity,thus, did not always go hand in handwith overweight/obesity. Abdominalobesity was found in 68.1 per cent ofmales with overweight (BMI>25) and58 per cent of females (Table 4). Inthese subjects, greater the grade ofBMI, the greater was the abdominaladiposity. It was noteworthy that nearly

a third of overweight males and morethan 40 per cent of the overweightfemales did not show abdominal obe­sity. On the other hand, nearly 19 percent of non-overweight male subjectswith BMI<25 and 22 per cent femalesshowed abdominal obesity (Table 4).

These data will show that in In­dian subjects, abdominal obesityfrequently, but not always, coexistswith general overweight/obesity. Ab­dominal obesity could be present inthe absence of general overweight/obesity also. Abdominal obesity wouldthus appear to be different with re­spect to its pathogenesis and pos­sible implications. The presence ofabdominal obesity aggravates the del­eterious effects arising from generaloverweight/obesity alone. It will beseen from the data in Table 5 that thesuperimposition of abdominal obe­sity had brought about a two-fold in­crease in the prevalence rate of highblood pressure in males and a three­fold increase in females.

Careful analysis of bio-chemi­cal findings of the study (Table 6)showed that higher the tertile valuesof BMI, higher were the mean valuesfor cholesterol, triglycerides, bloodsugar, LDL, VLDL and blood pres­sure. Similarly, with an increase inthe tertile values of WHR, there was asignificant increase in the mean val­ues of blood pressure, cholesteroland triglycerides. In subjects suffer­ing the additive effects of high BMIand distorted WHR, the values weresig nificantly worse. These observa­tions serve to underline the centralrole of overweight/obesity and theadditive deleterious effects of abdomi­nal obesity in the pathogenesis ofdisordered lipid and carbohydrate me­tabolism, leading to coronary heartdisease and diabetes mellitus (NIDDM).

DISCUSSION

It would appear from the datapresented above that nearly a third ofmales, and more than half of females,belonging to what may be termed the'upper middle class' in India are cur­rently overweight (BMI >25). The preva­lence of abdominal obesity in thisgroup is even higher. Assuming thatthe 'upper middle class' in India num­bers around 100 million (half the numberof middle class), it may be computedthat there are roughly 40 to 50 millionoverweight subjects belonging to theupper middle class in the country

today. If present trends continue, thesituation can get worse even within adecade, and overweight could emergeas the single most important publichealth problem in adults. Overweight/obesity may not be considered a spe­cific 'disease' but it is certainly the'mother' of important degenerativediseases in adult life. Prevention andcontrol of this problem must, there­fore, claim priority attention.

A possible genetic basis behindAsians being prone to abdominalobesity was suggested by observa­tions of McKeigue et a(6, who hadreported that Asian migrants exhib­ited greater proneness to syndromeX, characterised by higher levels ofBMI, prevalence of abdominal obe­sity, blood pressure, serum choles­terol and triglycerides. Bhatnagar eta(7 had shown in the Asian migrantsthe presence of increased Lp (a) lev­els which may imply diminished tol­erance to trans-fatty acids and greaterproneness to disordered lipid me­tabolism. On the other hand, Barkeret a(8 had suggested a possible etio­logic role of foetal undernutrition inthe proneness to syndrome X in adultlife. If Barker's hypothesis is right, itmay be argued that escalation in theprevalence of abdominal obesity is atransient phenomenon confined to ageneration of those born in poverty,with low birth-weights but who hadacquired affluence with all its attendentdeleterious effects in adult life. Withthe control of low birth-weights, fu­ture generations may be spared; butat this stage, this can only be aspeculation.

Genetic predisposition can findexpression only if potentiating fac­tors such as dietary errors and lack ofregular physical excercise are opera­tive. This should be obvious from the

near-absence of overweight/obesity/abdominal obesity in the slums andrural populations. Diets in India, andindeed in South Asia, are predomi­nantly based on cereals - wheat orrice - unlike Europe or North America.Much of the excessive dietary energyin overweight/obese South Asian sub­jects is, therefore, derived from car­bohydrates unlike in Europe. It hasbeen computed that as much as 20per cent of the ingested carbohy­drate (including starch and non-starchpolysaccarides) may be mal absorbedin the small bowel and may passbeyond the caecum to the colon to beacted upon by microbial flora and

4

converted into short chain fatty acids- acetic, propionic and butyric acids- which are wholly absorbed9-.2• There-fore, the possible role of excessivecarbohydrates in Indian diets, in theelevation of serum triglycerides (andabdominal obesity) would also re­quire consideration.

It is, however, reasonable to ex­pect that irrespective of the nature ofbasic predisposing factor(s) dietarydiscipline and regular physical excerciseshould be able to contain the problemof overweight/obesity.

The need for according highpriority to control the rising preva­lence of overweight/obesity/abdomi­nal obesity, especially, in the urbanmiddle class, must be appreciated.The problem could get worse in thedecades to follow. The most prudentand cost effective way of controllingthe disturbing escalation of CHD andNIDDM in Indian urban populationwould obviously consist in combat­ing the problem of overweight in them.

Apart from dietary errors andexcesses, lack of regular physicalexcercise in the urban middle classwith sedentary occupations, is a ma­jor underlying factor. In an earlierissue of the Bulletin, Shetty13 had dis­cussed the importance of physicalactivity in the control of CHD andNIDDM. The beneficial harmonal ef­fects of physical excercise and espe­cially its role in combating insulinresistance, a feature associated withabdominal obesity, are now betterunderstood.

The answer to the problem ofobesity is not to be found in the nu­merous 'instant slimming' centres thatare springing up in the mega cities ofIndia. The undesirable effects of drastic

weight reduction or of weight cyclingare now being recognised.

Among the positive strategiesthat can be adopted to retard theescalation of obesity in urban Indi­ans could be the following:

• An intensive programme of healtheducation through the media, on theproblem of overweight/obesity, de­signed to promote healthy dietary prac­tices and regular physical excercise.

• The provision of facilities for di­etary counselling and short periodsof daily physical excercise/training inlarge establishments (public/privatesector) employing large number of