BackgroundThe prevalence of hyperuricemia and gout has increased in recent decades. The role of dietary fructose in the development of these conditions remains unclear.ObjectiveTo conduct a systematic review and meta-analysis of prospective cohort studies investigating the association fructose consumption with incident gout and hyperuricemia.DesignMEDLINE, EMBASE and the Cochrane Library were searched (through September 2015). We included prospective cohort studies that assessed fructose consumption and incident gout or hyperuricemia. 2 independent reviewers extracted relevant data and assessed study quality using the Newcastle-Ottawa Scale. We pooled natural-log transformed risk ratios (RRs) using the generic inverse variance method. Interstudy heterogeneity was assessed (Cochran Q statistic) and quantified (I2 statistic). The overall quality of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.Results2 studies involving 125 299 participants and 1533 cases of incident gout assessed the association between fructose consumption and incident gout over an average of 17 years of follow-up. No eligible studies assessed incident hyperuricemia as an outcome. Fructose consumption was associated with an increase in the risk of gout (RR=1.62, 95% CI 1.28 to 2.03, p<0.0001) with no evidence of interstudy heterogeneity (I2=0%, p=0.33) when comparing the highest (>11.8% to >11.9% total energy) and lowest (<6.9% to <7.5% total energy) quantiles of consumption.LimitationsDespite a dose–response gradient, the overall quality of evidence as assessed by GRADE was low, due to indirectness. There were only two prospective cohort studies involving predominantly white health professionals that assessed incident gout, and none assessed hyperuricemia.ConclusionsFructose consumption was associated with an increased risk of developing gout in predominantly white health professionals. More prospective studies are necessary to understand better the role of fructose and its food sources in the development of gout and hyperuricemia.Protocol registration numberNCT01608620.

BackgroundVariation in the fat mass and obesity-associated gene (FTO) has been associated with susceptibility to obesity, but the association appears to be modified by diet. We investigated whether dietary protein intake modifies the association between FTO variant rs1558902 and body mass index (BMI) and waist circumference in young adults (n = 1491) from the cross-sectional Toronto Nutrigenomics and Health Study.ResultsLifestyle, genetic, anthropometric, and biochemical data were collected and diet was assessed using a Toronto-modified Willett Food Frequency Questionnaire. General linear models stratified by ethnicity and adjusted for age, sex, and total energy intake were used to examine the association between FTO genotypes and measures of body weight, and whether protein intake modified any of the associations. East Asians who were homozygous for the rs1558902 risk allele (A) had a greater BMI (p = 0.004) and waist circumference (p = 0.03) than T allele carriers. This association was not observed in individuals of Caucasian or South Asian ancestry. Among East Asians, a significant FTO-protein interaction was observed for BMI (p = 0.01) and waist circumference (p = 0.007). Those with low protein intake (≤ 18% total energy intake) who were homozygous for the rs1558902 risk allele (A) had significantly higher BMI (p <  0.0001) and waist circumference (p = 0.0006) compared to carriers of the T allele. These associations were absent in the high protein intake group (> 18% total energy intake). Compared to Caucasians and South Asians, East Asians consumed a significantly higher ratio of animal-to-plant protein (p <  0.05).ConclusionsThese findings suggest that high dietary protein intake may protect against the effects of risk variants in the FTO gene on BMI and waist circumference.

While Brassica oleracea vegetables have been linked to cancer prevention, the exact mechanism remains unknown. Regulation of gene expression by cross-species microRNAs has been previously reported; however, its link to cancer suppression remains unexplored. In this study we address both issues. We confirm plant microRNAs in human blood in a large nutrigenomics study cohort and in a randomized dose-controlled trial, finding a significant positive correlation between the daily amount of broccoli consumed and the amount of microRNA in the blood. We also demonstrate that Brassica microRNAs regulate expression of human genes and proteins in vitro, and that microRNAs cooperate with other Brassica-specific compounds in a possible cancer-preventive mechanism. Combined, we provide strong evidence and a possible multimodal mechanism for broccoli in cancer prevention.

Gluten consumption is associated with increased plasma α2-macroglobulin in young adults, which appears to be independent of celiac disease, suggesting possible effects of gluten on inflammation.

BackgroundHormonal contraceptive use may be associated with a reduction in some premenstrual symptoms, however, the evidence remains equivocal. The objectives of the present study were to investigate the associations between ethnicity and hormonal contraceptive use with premenstrual symptoms.MethodsOne thousand one hundred two women participating in the Toronto Nutrigenomics and Health Study provided data on their premenstrual symptoms and hormonal contraceptive use. Severity of symptoms was classified as none, mild, moderate, or severe. Prevalence of premenstrual symptoms was determined in the total population and among major ethnic groups. Logistic regressions were used to determine the association between ethnicity and prevalence of premenstrual symptoms. Logistic regressions were used to determine the associations between hormonal contraceptive use, and premenstrual symptoms, adjusting for ethnicity and other covariates.ResultsPrevalence of individual symptoms varied, and the most commonly reported were cramps (75%), bloating (75%), mood swings (73%), increased appetite (64%), and acne (62%). Prevalence of cramps differed between ethnic groups with East Asians reporting a lower prevalence than Caucasians and South Asians (p < 0.05). Use of hormonal contraceptives was associated with a lower RR (95% CI) of experiencing moderate/severe: cramps (0.82, 0.72-0.93), clumsiness (0.22, 0.07-0.73), confusion (0.22, 0.09-0.54) and desire to be alone (0.45, 0.28-0.73). Hormonal contraceptive use was not associated with the risk of premenstrual symptoms at mild severity. Hormonal contraceptive use was not associated with symptoms of anxiety, bloating, mood swings, increased appetite, acne, fatigue, sexual desire, depression, nausea, headache and insomnia.ConclusionThis study demonstrates that East Asians may be at a lower risk of experiencing premenstrual cramps and that hormonal contraceptive use is associated with a lower risk of experiencing many, but not all, premenstrual symptoms at moderate/severe severity.