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Carbohydrate sweeteners in the diet, which are sources of added sugars, have recently undergone changes that vary considerably among countries. The major driving force for these changes is a technological development that permits conversion of corn and other starches to sweeteners. Major changes in the type of sweeteners used in the United States began in the mid-1970s. In 1986 the US Food and Drug Administration comprehensively evaluated exposures and potential health effects of sugars contained in carbohydrate sweeteners. A UK Department of Health report followed in 1989. An overview of issues is provided, terminologies used to describe sugars and sweeteners are defined, the findings of the US and UK reports are reviewed, trends in the availability of added and naturally occurring sugars are evaluated, and recommendations for future assessment of sugars are discussed. The potential problem of underreporting of food intakes in national food consumption surveys is also reviewed.

It is increasingly appreciated that some foods and food components, including fructose, have specific health benefits and/or potential risks. This recognition is associated with varied health claims and cautionary statements that can drive dynamic changes in food manufacture, selection, consumption, and views about food safety. It is imperative that the scientific and public health communities develop clear standards for evaluating potential benefits and risks, a process for accurately conveying sound public health information to consumers, and a mechanism for monitoring future changes in the food supply and relating these changes to potential health effects. In this paper we discuss specific and general considerations about the health effects of dietary fructose and provide a perspective on their public health significance. On the basis of currently available information, there is little basis for recommending increased or decreased use of fructose in the general food supply or in products for special dietary use.

Fat substitutes, in theory, may provide special health benefits to certain population segments. The most probable benefits are a reduction in total fat intake and a subsequent reduction in intake of calories from fat. Whether individuals who consume high intakes of fat substitutes that are partially or totally nondigestible also benefit from lower calorie intake on a long-term basis is unknown. It is likely that many individuals will compensate by increasing total food intake to maintain calorie intake. Consumption of fat substitutes presents nutrition problems. Those fat substitutes that are partially or totally nondigested may reduce the bioavailability of other nutrients. Similarly, fat substitutes may have adverse effects on normal gastrointestinal tract function or intestinal tract flora. Unlike other functional food additives, fat substitutes can make up a significant portion of the total diet. For this reason, traditional safety factors cannot be applied. Consequently, more reliance on data from clinical studies involving human subjects and requirements for postmarket surveillance will be necessary as part of the approval process.

The science and policy underlying food labeling and food fortification have evolved over the past 30 years to a point where dietary guidance and nutrition labeling now provide consumers with highly sophisticated, very specific information about links between diet and health. The focus was once on prevention of nutrient deficiency diseases, but today it is on reducing the risk of chronic diseases and health-related conditions. The Nutrition Labeling and Education Act of 1990, with its provisions for authorization of health claims on food labels, has provided a gateway through which a broader realm of nutrition and health information can be made available to consumers. However, the interpretation and implementation of the health claim provisions must evolve, based on a strong foundation of supporting science, so that industry may more readily make health information available to consumers in a form that is easily understood and effectively used in making their dietary choices. We must develop a database to support claims of beneficial effects of food components. We must be assured that the beneficial effects are not outweighed by safety concerns. And we must develop an environment that is conducive to conducting the research to develop these data. This can only be accomplished through the collaborative efforts of industry, academia, consumers and public health agencies.

Partially purified rabbit skeletal muscle phosphorylase phosphatase (EC 3.1.3.17; phosphoprotein phosphohydrolase) was inactivated when it was incubated with exogenous cyclic AMP-dependent protein kinase (EC 2.7.1.37; ATP:protein phosphotransferase), cyclic AMP, and ATP-Mg. Subsequent separation of the phosphatase by acrylamide gel electrophoresis or sucrose density centrifugation resulted in reactivation of the enzyme. The phosphatase decreased in molecular weight from approximately 70,000 to 52,000, and a phosphorylated inhibitor with molecular weight of 26,000 was found. Reactivation of phosphatase also occurred when it was incubated with MnCl2 or trypsin. The inhibitor was effective at less than 10(-8) M and was relatively heat stable. Its activity was destroyed by tryptic digestion and by dephosphorylation by a Mn-stimulated phosphatase. These observations support the possibility that phosphorylase phosphatase activity is controlled by cyclic AMP-dependent protein kinase and a Mn-stimulated phosphatase by a reaction involving phosphorylation and dephosphorylation of a protein phosphatase inhibitor.

A critical review composed of two parts: estimates of present levels of sugars intake and of recent trends in nutritive carbohydrate sweetener content of the food supply and a review of recent scientific literature addressing potentially adverse health effects associated with sugars consumption. The review contains an executive summary, an appendix with 75 tables summarizing the estimation of sugars intake of U.S. population groups, and over one thousand citations.

With heat treatment (20 degrees C for 30 min), the glucocorticoid-receptor complex becomes ‘activated’ and undergoes an increase in affinity for DNA. A two-stage procedure was used to separate sequentially the rat liver glucocorticoid-receptor complex from proteins with high and low affinity for DNA. DNA-cellulose column chromatography of unheated cytosol resulted in the retention of DNA-binding proteins, but not the unactivated receptor complex. Heat treatment of the column eluate resulted in increased affinity of the receptor complex to DNA, and chromatography on DNA-cellulose then yielded receptor complex free from proteins with low affinity for DNA. Removal of DNA-binding proteins during the first chromatographic step was critically dependent on ionic conditions and the ratio of cytosol chromatographed to DNA-cellulose. A purification of 11000-fold (85% yield) was achieved by this procedure. The partially purified receptor complex was taken up by rat liver nuclei.