Is dietary fat "fattening"? A comprehensive research synthesis.
ABSTRACT The goal of this research synthesis was to separate and articulate questions that had clear meaning, were empirically addressable, and were germane to the broad question "Is fat fattening?" Four such questions addressing the effect of varying the proportion of dietary fat on body weight and body fat were formulated. A comprehensive review of electronic citation databases was conducted to identify studies that addressed each question. The results of the studies addressing each question were tabulated and summarized, and an answer for each question was formulated. The results indicated that whether "fat is fattening" depends on exactly what one means by the question. It is apparent that under conditions of energy deficit, high-fat diets lead to greater weight loss than low-fat diets, but under ad libitum feeding conditions, instructing persons to follow a low-fat diet promotes loss of body weight and body fat. For one question, studies were few but convincing that altering the proportion of energy from fat in daily snacks has no effect on weight, while for another there were not enough studies available to answer the question with confidence. General recommendations to reduce dietary fat to promote weight loss or maintenance in all circumstances may merit reconsideration.
- SourceAvailable from: Gaël Y Rochefort[Show abstract] [Hide abstract]
ABSTRACT: We carried out an in vivo study to assess the relationship between increase in adiposity in the marrow and osteocyte apoptosis in the case of alcohol-induced bone loss. After alcohol treatment, the number of apoptotic osteocytes was increased and lipid droplets were accumulated within the osteocytes, the bone marrow and the cortical bone micro-vessels. At last, we found an inverse correlation between bone mineral density and osteocyte apoptosis and strong significant correlations between the osteocyte apoptotic number and lipid droplet accumulation in osteocyte and bone micro-vessels. These data show that alcohol-induced bone loss is associated with osteocyte apoptosis and lipid accumulation in the bone tissue. This lipid intoxication, or 'bone steatosis', is correlated with lipid accumulation in bone marrow and blood micro-vessels.Alcohol and Alcoholism 05/2012; 47(4):413-22. DOI:10.1093/alcalc/ags057 · 2.09 Impact Factor
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ABSTRACT: Objective:Low-density lipoprotein-related receptor protein 1 (LRP1) is a multi-functional endocytic receptor and signaling molecule that is expressed in adipose and the hypothalamus. Evidence for a role of LRP1 in adiposity is accumulating from animal and in vitro models, but data from human studies are limited. The study objectives were to evaluate (i) relationships between LRP1 genotype and anthropometric traits, and (ii) whether these relationships were modified by dietary fatty acids.Design and methods:We conducted race/ethnic-specific meta-analyses using data from 14 studies of US and European whites and 4 of African Americans to evaluate associations of dietary fatty acids and LRP1 genotypes with body mass index (BMI), waist circumference and hip circumference, as well as interactions between dietary fatty acids and LRP1 genotypes. Seven single-nucleotide polymorphisms (SNPs) of LRP1 were evaluated in whites (N up to 42 000) and twelve SNPs in African Americans (N up to 5800).Results:After adjustment for age, sex and population substructure if relevant, for each one unit greater intake of percentage of energy from saturated fat (SFA), BMI was 0.104 kg m(-2) greater, waist was 0.305 cm larger and hip was 0.168 cm larger (all P<0.0001). Other fatty acids were not associated with outcomes. The association of SFA with outcomes varied by genotype at rs2306692 (genotyped in four studies of whites), where the magnitude of the association of SFA intake with each outcome was greater per additional copy of the T allele: 0.107 kg m(-2) greater for BMI (interaction P=0.0001), 0.267 cm for waist (interaction P=0.001) and 0.21 cm for hip (interaction P=0.001). No other significant interactions were observed.Conclusion:Dietary SFA and LRP1 genotype may interactively influence anthropometric traits. Further exploration of this, and other diet x genotype interactions, may improve understanding of interindividual variability in the relationships of dietary factors with anthropometric traits.International Journal of Obesity advance online publication, 29 January 2013; doi:10.1038/ijo.2012.215.International journal of obesity (2005) 01/2013; DOI:10.1038/ijo.2012.215 · 5.39 Impact Factor
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ABSTRACT: Emerging evidence from a number of laboratories indicates that humans have the ability to identify fatty acids in the oral cavity, presumably via fatty acid receptors housed on taste cells. Previous research has shown that an individual's oral sensitivity to fatty acid, specifically oleic acid (C18:1) is associated with body mass index (BMI), dietary fat consumption, and the ability to identify fat in foods. We have developed a reliable and reproducible method to assess oral chemoreception of fatty acids, using a milk and C18:1 emulsion, together with an ascending forced choice triangle procedure. In parallel, a food matrix has been developed to assess an individual's ability to perceive fat, in addition to a simple method to assess fatty food liking. As an added measure tongue photography is used to assess papillae density, with higher density often being associated with increased taste sensitivity.Journal of Visualized Experiments 06/2014; DOI:10.3791/51236