Estimating dietary intake from human stool DNA
Related Articles
Estimated human intake of endogenous and exogenous hormones from beef in the United States
Endogenous and exogenous hormones may be present in beef. Human consumption of hormones has been linked to adverse health effects.
Predictive equation derived from 6,497 doubly labelled water measurements enables the detection of erroneous self-reported energy intake
Nutritional epidemiology aims to link dietary exposures to chronic disease, but the instruments for evaluating dietary intake are inaccurate. One way to identify unreliable data and the sources of errors is to compare estimated intakes with the total energy expenditure (TEE). In this study, we used the International Atomic Energy Agency Doubly Labeled Water Database to derive a predictive equation for TEE using 6,497 measures of TEE in individuals aged 4 to 96 years. The resultant regression equation predicts expected TEE from easily acquired variables, such as body weight, age and sex, with 95% predictive limits that can be used to screen for misreporting by participants in dietary studies. We applied the equation to two large datasets (National Diet and Nutrition Survey and National Health and Nutrition Examination Survey) and found that the level of misreporting was >50%. The macronutrient composition from dietary reports in these studies was systematically biased as the level of misreporting increased, leading to potentially spurious associations between diet components and body mass index.
Neurotensin-neurotensin receptor 2 signaling in adipocytes suppresses food intake through regulating ceramide metabolism
Neurotensin (NTS) is a secretory peptide produced by lymphatic endothelial cells. Our previous study revealed that NTS suppressed the activity of brown adipose tissue via interactions with NTSR2. In the current study, we found that the depletion of Ntsr2 in white adipocytes upregulated food intake, while the local treatment of NTS suppressed food intake. Our mechanistic study revealed that suppression of NTS-NTSR2 signaling enhanced the phosphorylation of ceramide synthetase 2, increased the abundance of its products ceramides C20–C24, and downregulated the production of GDF15 in white adipose tissues, which was responsible for the elevation of food intake. We discovered a potential causal and positive correlation between serum C20–C24 ceramide levels and human food intake in four populations with different ages and ethnic backgrounds. Together, our study shows that NTS-NTSR2 signaling in white adipocytes can regulate food intake via its direct control of lipid metabolism and production of GDF15. The ceramides C20–C24 are key factors regulating food intake in mammals.
Dietary protein restriction elevates FGF21 levels and energy requirements to maintain body weight in lean men
Dietary protein restriction increases energy expenditure and enhances insulin sensitivity in mice. However, the effects of a eucaloric protein-restricted diet in healthy humans remain unexplored. Here, we show in lean, healthy men that a protein-restricted diet meeting the minimum protein requirements for 5 weeks necessitates an increase in energy intake to uphold body weight, regardless of whether proteins are replaced with fats or carbohydrates. Upon reverting to the customary higher protein intake in the following 5 weeks, energy requirements return to baseline levels, thus preventing weight gain. We also show that fasting plasma FGF21 levels increase during protein restriction. Proteomic analysis of human white adipose tissue and in FGF21-knockout mice reveal alterations in key components of the electron transport chain within white adipose tissue mitochondria. Notably, in male mice, these changes appear to be dependent on FGF21. In conclusion, we demonstrate that maintaining body weight during dietary protein restriction in healthy, lean men requires a higher energy intake, partially driven by FGF21-mediated mitochondrial adaptations in adipose tissue.
Quantifying vitamin D intake among Aboriginal and Torres Strait Islander peoples in Australia
Vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] concentration < 50 nmol/L) is prevalent among Aboriginal and Torres Strait Islander peoples in Australia. Alternative to sun exposure (the primary source of vitamin D), vitamin D can also be obtained from food (e.g. fish, eggs, and meat) and supplements. However, the vitamin D intake of this population group is unknown. We aimed to provide the first quantification of vitamin D intake using nationally representative data from Aboriginal and Torres Strait Islander peoples.
Responses