Sugar is intrinsically linked with the modern food system. Large sections of the U. K. food industry are dependent on its use and functional qualities. Supplies of sucrose entering the food chain have declined 25% between the 1950's and 1980's and currently stand around 37 kg/person/year. Furthermore, U. K. dietary guidelines over the past 14 years have consistently suggested caution over how much sugar is eaten, especially in manufactured foods. Dietary guidelines such as the NACNE report (1983) recommend average sugar consumption should be no more than 20 kg/person/year. Currently, two-thirds of sugar supplies are bought for use in food and drink manufacture. Continued pressures on sugar consumption and negative consumer attitudes to sugar may be reflected in lost sales of sugar-containing foods. The available information on U. K. sugar consumption is critically assessed. Although the main sources of sugar supply are identified, individual sugar consumption is shown to vary by considerable amounts. The place of sucrose is examined in relation to other sweeteners and why and where sugars and sweeteners are used in food systems. The promotion of "no added sugar" and "sugar free" products is examined since the publication of the NACNE report to the end of 1987. To further test the impact of changing patterns of sugar consumption on food and drink manufacturers a national survey of manufacturers who use sugar was carried out in early 1988. This was an attitudinal postal questionnaire and responses to the issue of sugar, diet and health were analysed. Respondents bought an estimated 650,000 tonnes of sugar in 1986, around 45% of the total industrial market. While the survey aggregate were fully supportive of sucrose, respondents reported that the majority of consumers were worried about sugar being bad for health and were actively cutting down on individual intakes. There were significant differences to the issue of sugar, diet and health dependent on company size, whether a company manufactured for a retailer's own label and if products had already been marketed at a "healthy eating" segment. However, in general, while manufacturers considered consumer attitudes to sugar to be important they had to be put in the context of other factors. So far the impact of changing patterns of sugar consumption is not reflected in the total average industrial purchases of sugar, although substantial "sugar-free" and "sugar-reduced" product niches have been established.

M. Tech. (Department of Biotechnology, Faculty of Applied and Computer Sciences), Vaal University of Technology. / Obesity has steadily increased and represents a major public health problem worldwide, reducing quality of life and causing a range of health problems. Obesity has emerged as the fifth leading risk of global deaths. Annually, 2.8 million adults die as a result of being overweight or obese. The increase of obesity remains inexplicable in terms of genetic susceptibility to obesity. The genetic loci identified by genome-wide association studies (GWASs) explains about 2% of the heritability for obesity. Perhaps other factors such as epigenetics may be involved in the increase of obesity and may offer solutions for the management of obesity. Epigenetics is defined as a heritable change in gene expression without altering the genome sequences. It may help in providing a logical explanation between the genome and environment which shapes obesity risk and may help to explain the "missing heritability". Epigenetics may affect two mechanisms, namely: i) DNA methylation,and ii) histone modifications. DNA methylation might give scientists a link to the rise in obesity.The study aimed to investigate the effect of sugars used as sweeteners in sugar-sweetened beverages (SSB) on DNA methylation in a Caco-2 cell line in vitro. Four major objectives were pursued in the study which were to:(1) stimulate the Caco-2 cells with varying concentrations of sugar sweeteners and assess the morphological changes of the cells; (2) evaluate the cytotoxicity of different concentrations of the sugar sweetener on the Caco-2 cell line using the Alamar blue and LDH assay; (3) obtain genomic DNA from the treated Caco-2 cell line and perform bisulfite conversion and rest; and (4) amplify the WT1, MEG3, TNFRSF9, ATP10A, and CD44 obesity-associated genes and ascertain their degree of methylation. Caco-2 cells were stimulated with sugar sweeteners at varying concentrations (low, medium and high) for an incubation period of 62 days,and images of the cells were captured for morphological characterisation. The incubation condition entailed cells plated in a 12 or 96 well plate, incubated in a humidified 5% CO2 incubator at 37 °C and there is nutrient renewal every three days.Alamar blue, a cell proliferation colourimetric assay and lactate dehydrogenase assays (LDH), a homogenous membrane fluorimetric assay were used for the cytotoxicity studies. The results of the characterisation showed that different concentrations of sugar sweeteners affected the morphology of the cells as the incubation period progressed. The cytotoxicity results of both LDH and Alamar blue depicted low concentration of sweeteners that had low-to-moderate toxicity and the medium and high concentration of the sweeteners had a moderate to high toxicity on the Caco-2 cells. DNA from the Caco-2 cells was extracted. Techniques used to study DNA methylation such as bisulfite conversion, PCR amplification and restriction enzymes that have differential sensitivity to 5-methyl-cytosine were performed. The quality of DNA extracted was good. The bisulfite conversion was conducted andno amplification was observed, as a contingency plan Normal PCR was performed to amplify the CpG islands, and there was amplification. In conclusion, the study showed that a low concentration of a sugar sweetener (fructose: glucose) used in beverages had low toxicity to the Caco-2 cell line and prolonged exposure of the low concentration might have an adverse effect on the cells' morphology. At medium concentrations, the sugar sweetener used in beverages had medium toxicity to Caco-2 cells; prolonged exposure may lead to morphological changes. These findings indicated that control of dietary glucose intake is an important strategy in combating the development of obesity and type-2 diabetes. DNA methylation could not be established.