Chapter 2 Page 1
CHAPTER 2. THE MAGNITUDE AND TRENDS OF
NUTRITIONAL PROBLEMS
1. Nutritional problems in developing countries
Undernutrition is taken broadly. To estimate the situation four broad categories have been proposed by WHO/FAO in the ICN 1992.
1. Chronic undernutrition 780 M
2. P.C.M.190 M
3. Micronutrient deficiencies:
Vit A : 40 M
Fe def: 2000 M
I def : 200 M
4. Diet related non-communicable diseases or the phenomenon of nutrition transition.
2. Estimating chronically undernourished
D.E.S. Dietary Energy Supply = average per caput energy availability, produced from Food Balance Sheets (FBS).
Energy need is BMR * 1.54 (previously BMR * 1.4).
But - Energy supply is not what is available for consumption
- Aggregated information: large variability between groups, regions,...
- Raw data: no losses, preparation, part used for animal foods,
Since 1965 according to FAO, the DES has increased, but with a wide variation between regions, see fig 1. Problem countries are particularly the Sub-Saharan countries and East-Africa. 18 million People are in urgent need.
2600 Kcal/p/d as cut off (2 SD more than the normal average per person, covers 95% of the population) : 1989-90; 41 countries above and 11 countries even below 2000 Kcal/p/d. 123 M live in critical conditions. The average energy needed per person is 2160 Kcal.
FAO global estimate = 780 M. Over all this is less than in 69-70 (941 M), which is a drop from 36 to 20% of the world population. A great disparity still exists between continents and countries, see fig 2. Percentages give a wrong idea!
Body Mass Index (B.M.I.) Recently more attention has been given to adult anthropometric measurements and to use a combination of adult and child measurements to assess a situation. Not much information available as yet. BMI U-shaped relation with life expectancy. BMI is related to low birth weight.
BMI <18.5 : undernourished
BMI 18.5-25 :normal
BMI > 30 : obese
BMI < 18.5 India: 50 %
Haiti: 25 %
Lat Am: 10 %
BMI > 30 Lat Am: 22-45 % - transition phenomenon, difficult to separate DC's and LDC's.
BMI decrease is an indication of a general nutritional problem.
BMI good in adults but PCM is high : Indicates that in general the energy availability is good but that other factors affect children in particular.
3. P.E.M.
The term protein energy malnutrition, has been used to describe a range of disorders primarily characterised by growth failure or retardation of children. Other terms are: multideficiency syndrome, failure to thrive. The extreme clinical cases are marasmus and kwashiorkor.
Growth deficit is catalogued as
Thinness or “wasting” using Weight for Height (W/H)
Linear growth retardation or “Stunting” using Height for Age (H/A)
Undernutrition: Weight for Age (W/A), result of wasting and/or stunting
or clinically as Kwashiorkor (K)
Marasmus (M)
Mixed: Marasmus-Kwashiorkor (MK)
Causes are complex and routed in poverty, inequity, diseases, insufficient nutrient intake, etc.
World situation: Table 3, figs 3 and 4.
% , absolute numbers ; Africa .
Note on the available information: information is relatively scant and non-existing on a number of countries. The problem is probably underestimated. Figures represent "normal" situations.
Infant and child mortality
Among infants and children, poor nutritional status and infection, as well as other environmental and socio-economic factors can lead to death. Infant mortality rates are strongly influenced by nutritional factors such as foetal undernutrition stemming from maternal undernutrition or infections; toxaemia of pregnancy and maternal anaemia. There is increasing evidence that the mother's nutritional status has a pervasive influence on infant nutrition and survival. Fig 5.
Under five mortality rates fig 6. 10-20/ 1000. Reflects a multitude of factors affecting survival; nutrition, infections, etc.
Low birth weight
Can be used as an indicator of maternal nutrition and the risk infants start off with in life.
LBW < 2500 gr. Other countries have chosen alternative cut-offs, mainly for operational purposes.
LBW 6.5 % DC and 20 LDC's.
Causes are different:
DC: smoking, short stature, low weight increase, young others
LDC: Low calorie intake, low pre-pregnant BMI, short stature, malaria, etc.
4. Micronutrient deficiencies.
What is new
Emphasis on micronutrient
Emphasis on the deficiency state and not on the clinical picture alone. Effects of deficiency without clinical signs. The problem is much larger than the clinically visible part.
A global problem, also in the north.
see table 4.
The three major deficiencies are iron deficiency, vitamin A deficiency and iodine deficiency, because they are widely prevalent and have negative effects on a wide range of health aspects.
Iodine
1000 M at risk
200 M deficient
26 M mentally deficient
6 M cretinism
Vitamin A
At risk 190 M
Deficient 40 M increased morbidity, mortality
Clinical signs: 13 M 1/4 - 1/3 become blind every year.
Fe deficiency
2000 M and everywhere. ± 50 % of women in DC's.
Other deficiencies
These are still prevalent and characterised by the fact that they exist in their well known “old” sites and are emerging in places where they did not exist before due to environmental changes, changing food habits and emergency situations which take large proportions.
Vit B1. beriberi:introduced in Africa with a new rice eating culture.
Niacin: pellagra:
Vit C. Refugee camps
Vit D: old and new due to pollution
Fluor: dental carries
Selenium: newly studied, risks attributable to the deficiency, but knowledge on prevalence and effects is still limited.
Zinc: Similar as selenium.
5. Diet related non communicable diseases.
First accent on non communicable aspect
Hypertension, C.V.A, MI, stroke, diabetes (non insulin dependant), obesity, dental carries, carcinomas, osteoporosis.
Recently are included food intoxication, listeria, salmonella, campylobacter, etc.
- They are the No.1 disease in the North
- Intensification of agriculture and livestock with contamination of the environment
- Urbanisation trend; In '75 39 % of the world population lived in cities, in '90 43 % and in 2000 51 % will live in cities. The largest increase will be noted in developing countries.
This gives competition for water, needs for transports and storage, the increased consumption of prepared foods in situations where technology has not caught up, quality control is weak, legislation is not up to date, etc. This will become an increasing problem.
Tendencies
Move in dietary pattern from the hunter-gatherer type to the auto-subsistence farming to micro-economy type. These changes involve a higher consumption of fats from animal origin, less carbohydrates and dietary fibre and more refined sugars.
GMP and dietary pattern.
Recommended fat intake: 15-30 % of total daily energy with an intermediate goal of 20%. In the Western type of diet this can reach 40 and more percent. Most of the fats are from animal origin and saturated. The production of this meat has also important environmental consequences. 4 Kcal of cereals are needed to produce 1 Kcal of cattle protein. The animals produce large amounts of CH4 (methane) which make up 30% of the greenhouse gas.
In developing countries fast changes are noticeable in mortality patterns and in dietary consumption with a decrease in carbohydrates, fibres and an increase in meat products and fat consumption. (Fig's 7,8; table 5)
Causes are:-change in life style, sedentary, stress
-change in feeding pattern fat, sugar, Energy, fibres.
Clear relation with obesity in children (fig 10).
Relationship between Carcinomas and food (table 6).
Conclusions
1. Energy deficiency.The situation is improving but the problem stays important. The population growth is the limiting factor. The expected decrease in population growth with decreasing IMR has not manifested itself. We are "trapped".
2. Micronutrient deficiencies.Very widespread, more important than estimated previously. "Hidden".
3. Nutritional transition.
4. Not a problem of "developing countries" alone.
Recommended reading
1.International conference on nutrition. Nutrition and development - a global assessment. FAO/WHO 1992.p 3- 26.
2. Diet nutrition and the prevention of chronic diseases. WHO technical report series. No 797.
3. Diet, nutrition and chronic disease. Lessons from contrasting worlds. Shetty PS & McPherson K Eds. London School of hygiene & Tropical Medicine Sixth Annual Health Forum. John Wiley & Sons. Chichester 1997.