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Addressing Malnutrition In South Africa.

Gary Klugman

South Africa is getting set to embark on a visionary National Food Fortification Program to address nutrient deficiencies. Scientists however, are beginning to question whether the program will actually achieve its objective of redressing nutrient deficiencies in children. Gary Klugman takes a look at the chemistry of the proposed national food fortification program and the anticipated efficaciousness. Get the facts and enter the debate. A national Food Fortification Program concerns EVERYONE.

 

World Declaration On The Survival, Protection And Development Of Children.

The children of the world are innocent, vulnerable and dependent. They are also curious, active and full of hope. Their time should be one of joy and peace, of playing, learning and growing. Their future should be shaped in harmony and co-operation. Their lives should mature, as they broaden their perspectives and gain new experiences.

But for many children, the reality of childhood is altogether different.

 
What is the Food Fortification Programme?

Food, or the lack of it, is one of the factors affecting the nutritional status of children in South Africa. The Department of Health (DOH) in South Africa are embarking on a multi-faceted program to address malnutrition (nutrient deficiencies), that is rife amongst children aged 1 - 9 years old. One of these is a National Food Fortification Program where it is recommended to fortify wheat, maize flour and retail sugar, three of the five most commonly consumed food vehicles as reported by the National Food Consumption Survey.

The National Food Consumption Survey reported that for South African children as a whole, the average dietary intake of energy, calcium, iron, zinc, selenium, vitamin A, vitamin D, vitamin C, vitamin E, riboflavin, niacin, and vitamin B6 was less than 67% of the Recommended Dietary Allowances (RDA), and in many cases below 50% of the Recommended Dietary Allowances.

(1) Among infants and pre-schoolers, the more prevalent forms of nutrient deficiencies are those of iron, vitamin A, iodine, protein, energy, riboflavin, calcium and zinc. According to international agencies, millions of children suffer from deficiencies of iron, iodine and vitamin A. The incidence of these problems is markedly higher in developing countries; however, infants in industrialized countries are not spared. Iron deficiency has no borders and in industrialized countries approximately 15% of infants consume insufficient amounts of dietary iron.

Consequences and Causes of Malnutrition 

Depending on the nutrient and the severity of deficiency, the consequences of malnutrition may include growth stunting, anorexia, susceptibility to infections, behavioral changes, and learning disabilities. The latter may have lifelong effects. For example, research has found that iodine deficiency and iron deficiency anaemia during infancy can cause mental retardation or inferior psychomotor function in childhood, even after the deficiencies have been corrected. The causes of these problems are multifactorial and include poverty, ignorance, faulty feeding practices, infections and infestations, food scarcity, consumption of foods of low nutrient density, and low bioavailability of food nutrients.

Internationally accepted criteria for food fortification programmes 

In South Africa food choices are limited and the amount of food consumed is relatively low, but for the age group of children 1 - 3 years of age the demand for nutrients is high, thus the fortification of foods has to adhere to internationally recognized principals, when selecting compounds to be used as fortificants:

1. Chemical structure. Physico-chemical characteristics.
2. Absorption mechanisms.
3. Bioavailability established by internationally recognized procedures.
4. Effectiveness as measured by field and clinical trials, using the compound as a supplement or in food fortification.
5. Acute, sub chronic and chronic toxicity studies.
6. Acceptability. No gastric problems. No organoleptic changes in foods. 
7. Regulation of absorption by body reserves.
8. Innocuousness.
9. Registered by International quality assurance organizations.

The Compounds to be included in the Food Fortification Programme

 The DOH and their advisors, selected and recommended the following compounds to be used as fortificants: 

Vitamin A Palmitate  Vitamin (B1) Thiamin Mononitrate
Vitamin (B2) Riboflavin  Vitamin (B3) Nicotinamide
Vitamin (B6) Pyridoxine HCl Folic Acid 
Reduced Iron (Electrolytic Manufactured, min 98% activity ) Zinc Oxide (min 80% activity)
Calcium Carbonate as carrier ( min 40% activity )

    Although the levels of the RDA have been recommended to be applied at 33% of the RDA, in a draft proposal dated 29th November 2001 (Regulations Governing the Fortification of Foodstuffs) the following dosage levels of nutrients per 200 g dry maize flour have been recommended;

Vitamin A 25% Vitamin B1 25% Vitamin B2 17% Vitamin B3 25% Vitamin B6 25% Folic Acid 17% Iron 50% Zinc 20%

Additional feed back on Folic Acid dosage levels is still outstanding

How much would a child need to consume to reach these levels? 

The portion sizes to be fortified of dry maize & wheat flour have been recommended to be 200g. Maize flour has a swell factor of 2.5 = 500 g cooked maize porridge. Wheat flour converted to bread will = 333g or 11 slices at 30 g each. 

What about the stability of the nutrients? Can Vitamin A RDA levels be achieved? 

*Due to the instability of vitamin A when added to a premix and losses of the vitamin over the shelf life of the product and general losses when heated, for reconstitution, overages of vitamin A, at 142% have been included in maize flour to attain the desired dosage levels upon consumption, namely 25% of the RDA. ( please note the RDA values are based on adult requirements ) Thus theoretically the dosage of vitamin A delivered per 500g cooked maize flour will be 250 RE.

On evaluation of vitamin A needs for children in the age group 1 - 3 years old, the RDA requirements are 400 RE, thus in theory a child consuming 200g dry maize porridge a day will obtain 62.5% of their vitamin A needs.

The CSIR " Division of Food Science and Technology; Report; Storage Test of Fortified Maize Meal and Bread Flour, October 2000 " L Kyper Reported losses of vitamin A in storage conditions (shelf life of maize flour) and after cooking (reconstitution) at values of 142%.

The DOH are recommending the addition of 1,920 RE vitamin A per kg of maize flour. 5 portion sizes per kg of maize flour will yield a total of 384 RE per 200g dry maize flour. The reported losses of 142% vitamin A activity in maize flour, must be deducted to equate to vitamin A levels upon consumption, i.e. 200g of dry maize flour will contribute 40% of the RDA or 158 RE vitamin A. This equates to 40% of the RDA values for children 1 - 3 years of age, if they consume 500g of cooked maize porridge a day?

If the dietary adequacy of vitamin A is still less than 50% of the RDA amongst the most vulnerable group of children, it is unlikely to have the desired effect of preventing or curing vitamin A deficiency, as levels of vitamin A repleteness and vitamin A stores will not be maintained.

How effective will the choice of iron be in alleviating deficiency? 

The choice of iron compound for the DOH food fortification program is "Reduced Iron ". It is electrolyticaly manufactured and has extremely poor bioavailability factors, especially with particle sizes as stipulated by the DOH to be in the region of 45 micrometers in diameter. (2) Reduced Iron, commercial food grade, is absorbed at only 0.2% in foods. The recommended dosage level is 7.4mg per 200g dry maize flour. The RDA, needs for children aged 1 - 3 years old is 10mg. Taking the bioavailability factor of 0.2% in a 200g dry maize flour portion size, 500g cooked maize porridge, a child will receive only 0.0014mg Fe a day!

Could an alternative to reduced iron be used? 

The use of Reduced Iron of smaller particle sizes may offer an improvement, but still does not reach bioavailability of a more suitable alternative, ferrous sulphate. Studies using " Reduced Iron " ( Electrolytically Manufactured ) with particle sizes of 10 micrometers in diameter or less show that absorption was still only half that of Ferrous Sulphate. Ferrous Sulphate has a bioavailability factor of 2% in a diet rich in phytates. Thus, even at a bioavailability factor of 1% using smaller particle sizes of reduced iron, it will still only deliver 0.074mg, as a contribution to the child's daily needs of 10mg, and only if 500g of maize porridge can be consumed a day.

We are unable to find any bioavailability studies on Zinc Oxide in maize flour or wheat flour.

What about the combinations of metals - will there be interference? 

Metal to metal antagonsim/interference can not be intentionally ignored. (3) If calcium carbonate will be used as the carrier of the nutrients, it is most likely to interfere with the absorption of iron. (4) Ratios of non-heme iron to zinc of 2:1 and 3:1 have been shown to inhibit zinc absorption. It is also known that phytates inhibit the absorption of iron and zinc.

One last point on Parasites 

Parasitic infestation is also known to contribute to blood and iron loss. (5) A. duodenale, N. americanus, T.trichiura can have a negative impact on the iron status of children in South Africa, if not addressed prior to the implementation of a fortification program.

The DOH have shown a great vision to address malnutrition and must be admired for their efforts and endeavours. All parties concerned that have a true desire to address the scourge of poverty and malnutrition should assist the DOH in obtaining its objective without losing sight of delivering a cost effective fortification program together with a myriad of other interventions that will run parallel towards the upliftment and improvement in nutrient density of staple foods, supplementation programs, education and communication programs, mass dosage vitamin A, deparasitising programs etc for a better, brighter future of the targeted population most in need.


*(Please note, due to the home baking method used by the CSIR, Food Science and Technology Division, in the baking of breads for sensory and stability tests, we are unable to use the results as a reference.)

More Information:

Gary Klugman Director CELANEM. Regional Office For Africa Latin American Center For Nutrition And Metabolic Studies Consultants in Biochemistry, Nutrition and Applied Nutrition.

Contact Gary Klugman at +27 (0) 21 981 7600 or at klugman@aroma.co.za

References:

(1) David L. Yeung; Iron and micronutrients; complimentary food fortification;

(2) Bioavailability of different iron compounds in food; Brise & Halberg, Acda Med Scand 1960; supp. 368. Pineda, et al, J Appl Nutr 1984;46:2-13; Martinez-Torres, et al, 1986 J Nutr 116: 1720-25; Kalwasser, et al, 1987;37:122-29

(3) Intestinal Absorption of metal ions and chelates;1985 Charles C Thomas. Publisher; H. DeWayne Ashmead, Ph.D.; Darrell J. Graff, PH.d.; Harvey H. Ashmead, Ph.D.

(4) Solomons NW, Jacob RA. Studies on the bioavailability of zinc in humans; Effects of heme and nonheme iron on the absorption of zinc. Am J Clin Nutr, 1981;34:475-482

(5)Holland, Clin Nutr, 1989;8239-50







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