South African Journal of Clinical Nutrition - Volume 17, Issue 2, July 2004

We hope that all of you have received your 2003 point status and invoice for payment of the 2004 CPD administration fee (we hope you have noticed the rebate provided as a once-off by the CPD committee). Please note that the due date for this fee is 1 August 2004.

Although real, perceptions may be uninformed, misinformed and even invalid. If widely held such perceptions are extremely misleading, particularly to consumers, and adversely impact on their food choices and food purchasing patterns. With regard to nutrition, it is unfortunate that such perceptions abound on a number of issues, with edible fats and oils no exception.

This paper briefly reviews the role of dietary fats (lipids) in human nutrition, summarises the contribution to the symposium on fats and oils during the 2000 South African Nutrition Congress, and examines the present recommendations and controversies regarding fat intake, in order to examine whether in a developing country such as South Africa, dietary fat recommendations to consumers should be more explicit, specific and detailed. It is concluded that to reach 'optimal' intakes, some groups in South Africa (e.g. rural blacks) should increase intakes, while those at risk for cardiovascular disease should lower intakes. It is suggested that all South Africans over the age of 2 years should aim for an intake in which fat provides approximately 30% of total energy. To meet the guidelines that more omega-3 (& #969; -3), proportionally more monounsaturated fatty acids and less trans and saturated fatty acids should be eaten, alternative sources of and for these fatty acids in the South African diet should be promoted. Both consumers and the food industry should be targeted with information and advice to make healthier but affordable choices possible. Only then will dietary advice on the quality of fat (less saturated and trans fatty acids and more monounsaturated and (& #969; 3 fatty acids) be practical and meaningful.

Objective. To assess ascorbic acid (AA) losses in four vegetables (broccoli, peas, cauliflower and cabbage) at each production stage in a cook-chill food service system.

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Setting. A long-stay psychiatric hospital in Cape Town.

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Design. Cross-sectional analytical study. On two repeat occasions, three samples of each vegetable were taken at the following stages: (i) delivery (day 1); (ii) after preparation (day 2); (iii) after cooking (day 5); (iv) after blastchilling (day 5); and (v) in the holdroom and after regeneration over a 4-day period (days 6 - 9). AA content of each sample was assessed in duplicate using the 2, 6-dichloroindophenol method of titration.

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Statistical analyses. Differences between the AA concentration of each vegetable at baseline (delivery) and at subsequent stages in food production were assessed using analysis of variance (ANOVA) methods.

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Results. The most dramatic AA losses occurred during the cooking stage (mean loss 58%, standard deviation (SD) 19.5%, range 33 - 81%), with broccoli showing the greatest mean loss of 81% (SD 2.9%). During storage in the holdroom from day 6 to day 9, the average daily loss was 4.3% (SD 4.2%). Further average losses of 6.1% (SD 3.6%) were incurred after regeneration on each day. Mean AA losses on day 6 of production and after regeneration (the earliest time a patient would receive the vegetable) were 87% (SD 5.6%). On day 9 after regeneration (the latest time it could be received by a patient) mean losses were 89% (SD 10.5%).

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Conclusion. Use of a cook-chill food service system needs to be carefully controlled in order to minimise AA losses. In particular, prolonged cooking times should be avoided and vegetables should be immersed into rapidly boiling rather than cold water. A reduction of the number of days in the chilled storage holdroom would not substantially reduce overall AA losses.

Malnutrition, and its consequences, is a major problem facing the developing world today. World Health Organisation (WHO) figures indicate that 28% of all children under 5 years of age are underweight, 35% are stunted, and 8% are wasted. In 1987 the Nordic Conference on Environment and Development estimated that 500 million people in the world were undernourished. The problem, however, is not restricted to the developing world, with a number of studies reporting that up to 50% of hospitalised patients in developed countries may be nutritionally depleted.

The importance of nutritional support of the hospitalised patient is being increasingly recognised. Patients are frequently malnourished, with a recent study performed at Groote Schuur Hospital indicating that more than 40% of patients admitted for surgery were nutritionally depleted (C Hartman, 2000 - unpublished data). These figures are in agreement with published data from other centres where malnutrition rates approaching 50% of hospitalised patients have been reported. Of particular concern was that nutritional status was not adequately appreciated in 40% of these patients, and they did not receive additional nutritional support while in hospital.

Every time I sit to type a letter for the Journal, my thoughts are about time! The realisation that another 3 months have passed so quickly is unnerving. Which brings me to the issue of the International Nutrition Congress. You should have received an information booklet, detailing a full and exciting programme. Do not miss the early registration date.

The Nutrition Society of South Africa is a scientific organisation and the main aims are to advance the scientific study of nutrition; to promote objective dissemination of knowledge related to nutrition; and to promote strategies for the improvement of nutrition well-being. Welcome to the new news page of the Nutrition Society of South Africa. Watch this space in future for interesting information from the Society. Background information According to the Health Professions Act 56 of 1974 (section 33), all persons active in the scope of nutrition must be registered.

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