Nutrition
-
There is a significant amount of controversy related to the optimal amount of dietary carbohydrate. This review summarizes the health-related positives and negatives associated with carbohydrate restriction. On the positive side, there is substantive evidence that for many individuals, low-carbohydrate, high-protein diets can effectively promote weight loss. ⋯ LCDs that are high in saturated fat appear to raise low-density lipoprotein cholesterol and may exacerbate endothelial dysfunction. However, for the significant percentage of the population with insulin resistance or those classified as having metabolic syndrome or prediabetes, there is much experimental support for consumption of a moderately restricted carbohydrate diet (i.e., one providing approximately 26%-44 % of calories from carbohydrate) that emphasizes high-quality carbohydrate sources. This type of dietary pattern would likely lead to favorable changes in the aforementioned cardiovascular disease risk factors, while minimizing the potential negatives associated with consumption of the more restrictive LCDs.
-
The aim of this study was to investigate the effects of excess body fat on bone mass in overweight, obese, and extremely obese adolescents. ⋯ The results reveal a negative effect of BF% on bone mass in males and indicate that the higher the BF% among overweight adolescents, the lower the BMD and BMC values.
-
Comparative Study
Effects of low carbohydrate diets on energy and nitrogen balance and body composition in rats depend on dietary protein-to-energy ratio.
Truly ketogenic rodent diets are low in carbohydrates but also low in protein. The aim of this study was to differentiate effects of ketosis, low carbohydrate (LC) and/or low-protein intake on energy and nitrogen metabolism. ⋯ These results suggest that truly ketogenic LC diets in growing rats are LC diets that are also deficient in protein for growth.
-
With aging, kidney function declines, as evidenced by reduced glomerular filtration rate. It is controversial whether or not high protein intake accelerates this decline. The aim of this study was to determine whether high protein intake was associated with declines in kidney function among older patients. ⋯ These data suggest that higher protein intake does not have a major effect on kidney function decline among elderly men and women.
-
Probiotics may improve intestinal health by modulating intestinal microbiota. However, the age-related variation in response to probiotic consumption is understudied. The aim of this study was to determine the effect of oral consumption of Lactobacillus plantarum P-8 (Lp-8) on human intestinal microflora, secretary immunoglobulin A (SIgA), total bile acids (TBAs), and short-chain fatty acids (SCFAs) of different aged adults. ⋯ Lp-8 administration could improve human gastrointestinal health. However, some of these effects were transient and gradually disappeared once the intervention was discontinued. Moreover, the extent of these desirable effects was age-related.