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ment was with moderate doses of insulin, despite the enormously raised blood-sugar levels, and 0 45% saline infusions. Besides the physiological, biochemical, and clinical approaches to diabetes, another way in which the problem has been studied is with epidemiological techniques.8 One of the many interesting facts to emerge from this type of investigation is the relative impairment of glucose tolerance if the test is performed in the afternoon instead of in the morning. This observation indicates one difficulty in interpreting the results of a glucose tolerance test and points to the need for further research into the mechanisms that determine the shape of the tolerance curve. Epidemiological studies have also provided a stimulus to work on the relationships between carbohydrates, fats, and atherosclerosis. Though no absolutely clear pattern has yet emerged, it does appear that our eating habits play a part in determining whether or not we suffer from ischaemic heart disease and that the nature and timing of our carbohydrate and fat intake may be important causes of it.9 Other fields in which there have been recent advances in carbohydrate research include disorders of digestion and absorption, glycogen storage diseases, and galactosaemia. In his review of the first of these B. Levin'0 describes the clinical features, diagnosis, and pathophysiology of a wide variety of conditions. As well as being clinically important they shed light on the biochemical mechanisms. An example of this is the rare glucose-galactose malabsorption syndrome, which provides evidence of a common transport system by which these two monosaccharides leave the gut. Conversely, clinical medicine benefits from carbohydrate biochemistry. For example, it is possible by biochemical methods to detect heterozygous carriers of the various enzyme deficiencies that result in the pathological deposition of glycogen'1 as well to provide methods for monitoring treatment in conditions such as galactosaemia.12 This symposium report shows that research into the carbohydrate disorders is advancing steadily and that much of the success is due to joint research by clinicians, epidemiologists, and biochemists.