Adiposity and dietary intake in cardiovascular risk in an obese population from a Mediterranean area

Olive Oil, Palm Oil, and Hybrid Palm Oil Distinctly Modulate Liver Transcriptome and Induce NAFLD in Mice Fed a High-Fat Diet

Nonalcoholic fatty liver disease (NAFLD) is highly prevalent worldwide. The most severe form is nonalcoholic steatohepatitis (NASH). Among risk factors for the development of NAFLD is excessive lipid intake. Since palm (P) oil is the most consumed oil in the world, we aimed to investigate the effects of high-fat diets made with P oil, hybrid palm (HP) oil, or olive (O) oil in liver. Twenty-four male mice (C57Bl/6J) were fed a high-fat diet (41% fat) containing P, HP, or O oils for 8 weeks and compared to a control (C) group fed a chow diet. Adiposity was measured with computed tomography. Body, adipose tissue, and liver weights, as well as liver fat (Bligh–Dyer), blood lipid profile, glucose, and liver enzymes were measured. Liver histology (hematoxylin–eosin) and transcriptome (microarray-based) were performed. ANOVA tests with Newman–Keuls were used. Body weight was increased in the P group (p < 0.001) and body fat in the O group (C vs. O p ≤ 0.01, P vs. O p ≤ 0.05, HP vs. O p ≤ 0.05). All high-fat diets disturbed the blood lipid profile and glucose, with marked effects of HP on very low-density lipoprotein cholesterol (VLDL), triglycerides, and alkaline phosphatase (p ≤ 0.001). HP had the highest liver fat (42.76 ± 1.58), followed by P (33.94 ± 1.13). O had a fat amount comparable to C (16.46 ± 0.34, 14.71 ± 0.70, respectively). P and HP oils induced hepatocyte ballooning. Transcriptome alterations of the O group were related to amino acid metabolism and fatty acid (FA) metabolism, the P group to calcium ion homeostasis, and HP oil to protein localization. Both P and HP oils induced NASH in mice via disturbed hepatocyte transcription. This raises concerns about the content of these oils in several industrialized foods.

Does high-carbohydrate intake lead to increased risk of obesity? A systematic review and meta-analysis

OBJECTIVES

The present study aimed to test the association between high and low carbohydrate diets and obesity, and second, to test the link between total carbohydrate intake (as a percentage of total energy intake) and obesity.

SETTING, PARTICIPANTS AND OUTCOME MEASURES

We sought MEDLINE, PubMed and Google Scholar for observation studies published between January 1990 and December 2016 assessing an association between obesity and high-carbohydrate intake. Two independent reviewers selected candidate studies, extracted data and assessed study quality.

RESULTS

The study identified 22 articles that fulfilled the inclusion and exclusion criteria and quantified an association between carbohydrate intake and obesity. The first pooled strata (high-carbohydrate versus low-carbohydrate intake) suggested a weak increased risk of obesity. The second pooled strata (increasing percentage of total carbohydrate intake in daily diet) showed a weak decreased risk of obesity. Both these pooled strata estimates were, however, not statistically significant.

CONCLUSIONS

On the basis of the current study, it cannot be concluded that a high-carbohydrate diet or increased percentage of total energy intake in the form of carbohydrates increases the odds of obesity. A central limitation of the study was the non-standard classification of dietary intake across the studies, as well as confounders like total energy intake, activity levels, age and gender. Further studies are needed that specifically classify refined versus unrefined carbohydrate intake, as well as studies that investigate the relationship between high fat, high unrefined carbohydrate-sugar diets.

PROSPERO REGISTRATION NUMBER

CRD42015023257.

Associação entre consumo de alimentos embutidos e obesidade em um estudo de base populacional de nipo-brasileiros

OBJETIVO: Investigar a associação entre consumo de alimentos embutidos e obesidade generalizada, abdominal e generalizada com abdominal em nipo-brasileiros de Bauru, SP. SUJEITOS E MÉTODOS: Quatrocentos e quarenta e três mulheres e 329 homens nipo-brasileiros não miscigenados (≥ 30 anos) foram avaliados em estudo transversal de base populacional. Para o diagnóstico de obesidade, foram empregados os critérios da Organização Mundial da Saúde para asiáticos. A ingestão de alimentos foi avaliada por meio de questionário de frequência alimentar validado. A ingestão foi estratificada em terços para análise. RESULTADOS: Nos homens, a ingestão de colesterol e alimentos embutidos mostrou-se positivamente associada à obesidade generalizada com abdominal quando o primeiro terço de ingestão foi comparado ao último, após ajustes (OR 2,97; IC95% 1,13-7,78). Em mulheres, somente o grupo das carnes vermelhas associou-se à obesidade geral com abdominal após ajustes (OR 0,47; IC95% 0,23-0,96). CONCLUSÃO: Ingestão elevada de alimentos embutidos associou-se à obesidade generalizada com adiposidade abdominal em homens nipo-brasileiros, mas não em mulheres.

CLOCK genetic variation and metabolic syndrome risk: modulation by monounsaturated fatty acids

BACKGROUND

Disruption of the circadian system may be causal for manifestations of the metabolic syndrome (MetS).

OBJECTIVE

The objective was to study the associations of 5 CLOCK polymorphisms with MetS features by analyzing fatty acid (FA) composition from dietary and red blood cell (RBC) membrane sources.

DESIGN

Participants (n = 1100) in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study were included. Dietary intake was estimated with a validated questionnaire. Anthropometric and biochemical measurements and genotypes were determined. Postprandial lipids and the FA composition of RBC membranes were analyzed.

RESULTS

CLOCK single nucleotide polymorphisms were significantly associated with obesity and individual components of MetS. For single nucleotide polymorphism rs4580704, minor allele carriers had a 46% lower risk of hypertension than did noncarriers. The monounsaturated fatty acid (MUFA) content of RBC membranes, particularly oleic acid, changed according to CLOCK genetic variants (P < 0.05). We identified significant gene-diet interactions associated with MetS at the CLOCK locus. By dichotomizing MUFA intake, we found different effects across rs4580704 genotypes for glucose (P = 0.020) and insulin resistance (P = 0.026). The protective effect of the minor allele on insulin sensitivity was only present when MUFA intake was >13.2% of energy. We also found different effects across CLOCK 3111T-->C genotypes for saturated fatty acid intake (% of energy) (P = 0.017). The deleterious effect of gene variants on waist circumference was only found with high saturated fatty acid intakes (>11.8%).

CONCLUSIONS

CLOCK polymorphisms interact with FAs to modulate MetS traits. The dietary source and membrane content of MUFAs are implicated in the relations between alterations in the circadian system and MetS.

Age-related changes in fatty acids from different adipose depots in rat and their association with adiposity and insulin

OBJECTIVE

We studied age-related changes in fatty acids (FAs) from serum and adipose tissue in rats by comparing different adipose regions and analyzed their relations to adiposity and insulin function.

METHODS

Female weaned rats were fed on a high-fat diet until 6, 14, and 20 mo of age (n = 12, n = 6, n = 10, respectively). Body weight, adiposity, serum insulin, serum glucose, and homeostatic model assessment index were measured. FA compositions from serum and interscapular brown, periovarian, mesenteric, and subcutaneous tissues were determined by gas chromatography.

RESULTS

Body weight and adiposity increased with age; visceral depots grew by hypertrophy, whereas subcutaneous depots grew by hyperplasia and in a higher ratio. Initially, the mesenteric tissue showed greater saturated and trans-FA contents, whereas brown tissue had higher polyunsaturated FA (PUFA) proportions. Aging resulted in a lower saturation degree in adipose tissue, attenuating earlier differences among depots. There was an elevation in omega-6 PUFAs with age, mainly because of C18:2omega-6, whereas omega-3 long-chain PUFAs, C20:5omega-3 and C22:6omega-3, tended to decrease in serum and adipose tissue. Adiposity was associated positively with monounsaturated FAs and inversely with PUFAs; insulin-related variables correlated negatively with serum omega-6 PUFA but positively with serum monounsaturated FAs and subcutaneous depot trans-FAs.

CONCLUSION

The mesenteric tissue showed the least favorable FA profile compared with the other depots, but differences among adipose regions diminished with age. In rats fed a high-fat diet, aging resulted in a lower saturation degree, with increased values in the cardiometabolic risk factor omega-6/omega-3 ratio in serum and adipose tissue.

Personal and professional correlates of US medical students' vegetarianism

OBJECTIVE

To determine prevalence and correlates of US medical students' self-identification as vegetarians.

DESIGN

Medical students were anonymously surveyed via questionnaire three times: at freshmen orientation, orientation to wards, and during senior year.

SUBJECTS

Medical students in the Class of 2003 (n=1,849) at 15 US medical schools (response rate 80%).

OUTCOME MEASURES

We examined self-reported vegetarianism, abstinence from meat items on a food frequency questionnaire, and associations between students' vegetarianism and their health-related outcomes.

STATISTICAL ANALYSES

Bivariate associations were tested with chi(2) tests.

RESULTS

During medical school, 7.2% of students self-identified as vegetarians; this percentage declined over time. Those who were vegetarians for health reasons (66% of vegetarians) ate more fruits and vegetables than those who were vegetarians for nonhealth reasons (P=0.02). Vegetarians were more likely (P<0.01) than nonvegetarians to eat more fruits and vegetables (P=0.002); be women (P=0.009); be Hindu, Buddhist, or Seventh Day Adventist (P< or =0.0004); be politically liberal (P=0.007); have a body mass index < or =25 (P=0.008); or, as freshmen, to perceive nutrition counseling as highly relevant to their intended practices (P=0.007). Vegetarian students were no more likely to counsel patients about nutrition than were nonvegetarians.

CONCLUSIONS

Prevalence of vegetarianism was higher among US medical students than among other US adults, although the prevalence declined during medical school. Medical students and physicians with healthful personal practices are more likely to encourage such behaviors in their patients, although the specific nutrition habit of vegetarianism among medical students was unassociated with their nutrition counseling practices.

Potential effects of the next 100 billion hamburgers sold by McDonald's

BACKGROUND

McDonald's has sold >100 billion beef-based hamburgers worldwide with a potentially considerable health impact. This paper explores whether there would be any advantages if the next 100 billion burgers were instead plant-based burgers.

METHODS

Nutrient composition of the beef hamburger patty and the McVeggie burger patty were obtained from the McDonald's website; sales data were obtained from the McDonald's customer service.

RESULTS

Consuming 100 billion McDonald's beef burgers versus the same company's McVeggie burgers would provide, approximately, on average, an additional 550 million pounds of saturated fat and 1.2 billion total pounds of fat, as well as 1 billion fewer pounds of fiber, 660 million fewer pounds of protein, and no difference in calories.

CONCLUSIONS

These data suggest that the McDonald's new McVeggie burger represents a less harmful fast-food choice than the beef burger.