Associations between genetically determined dietary factors and risk of autism spectrum disorder: a Mendelian randomization study.

Background: Existing studies confirm the importance of dietary factors in developing autism spectrum disorder (ASD) and disease progression. Still, these studies are primarily observational, and their causal relationship is unknown. Moreover, due to the extensive diversity of food types, the existing research remains somewhat limited in comprehensiveness. The inconsistency of the results of some studies is very disruptive to the clinic. This study infers a causal relationship between dietary factors on the risk of developing ASD from a genetic perspective, which may lead to significant low-cost benefits for children with ASD once the specificity of dietary factors interfering with ASD is confirmed. Methods: We performed a two-sample Mendelian randomization (MR) analysis by selecting single nucleotide polymorphisms (SNPs) for 18 common dietary factors from the genome-wide association study (GWAS) database as instrumental variables (IVs) and obtaining pooled data for ASD (Sample size = 46,351) from the iPSYCH-PGC institution. Inverse variance weighted (IVW) was used as the primary analytical method to estimate causality, Cochran's Q test to assess heterogeneity, the Egger-intercept test to test for pleiotropy and sensitivity analysis to verify the reliability of causal association results. Results: The MR analysis identified four dietary factors with potential causal relationships: poultry intake (fixed-effects IVW: OR = 0.245, 95% CI: 0.084-0.718, P < 0.05), beef intake (fixed-effects IVW: OR = 0.380, 95% CI: 0.165-0.874, P < 0.05), cheese intake (random-effects IVW: OR = 1.526, 95% CI: 1.003-2.321, P < 0.05), and dried fruit intake (fixed-effects IVW: OR = 2.167, 95% CI: 1.342-3.501, P < 0.05). There was no causal relationship between the remaining 14 dietary factors and ASD (P > 0.05). Conclusion: This study revealed potential causal relationships between poultry intake, beef intake, cheese intake, dried fruit intake, and ASD. Poultry and beef intake were associated with a reduced risk of ASD, while cheese and dried fruit intake were associated with an increased risk. Other dietary factors included in this study were not associated with ASD.

Demographic and Socioeconomic Correlates of Disproportionate Beef Consumption among US Adults in an Age of Global Warming.

Concern for the environment when making dietary choices has grown as the contribution of the food sector to global greenhouse gas emissions becomes more widely known. Understanding the correlates of beef eating could assist in the targeting of campaigns to reduce the consumption of high-impact foods. The objective of this study was to identify the demographic, socioeconomic, and behavioral correlates of disproportionate beef consumption in the United States. We analyzed 24-h dietary recall data from adults (n = 10,248) in the 2015-2018 National Health and Nutrition Examination Survey (NHANES). Disproportionate beef consumption was defined as an intake greater than four ounce-equivalents per 2200 kcal. Associations of this indicator variable with gender, age, race/ethnicity, education, family income, diet knowledge, and away-from-home meals were assessed using logistic regression, incorporating survey design and weighting. Disproportionate beef diets were consumed by 12% of individuals, but accounted for half of all beef consumed. Males were more likely than females (p < 0.001) to consume these diets. This relationship was seen in all bivariate and multivariable models. Older adults, college graduates, and those who looked up the MyPlate educational campaign online were less likely (p < 0.01) to consume a disproportionate beef diet. While almost one-third of reported consumption came from cuts of beef (e.g., steak or brisket), six of the top ten beef sources were mixed dishes: burgers, meat mixed dishes, burritos and tacos, frankfurters, soups, and pasta. Efforts to address climate change through diet modification could benefit from targeting campaigns to the highest consumers of beef, as their consumption accounts for half of all beef consumed.

Multivariate analysis of heavy metals content of beef from Soroti, Uganda.

Information about food hygiene and quality in the sub-Saharan African countries remains scarce at a time when many of their citizenry are beginning to acquire the much coveted middle income status. Confounding this are challenges linked to monitoring on a continuous basis the safety of food produced by such lucrative industries as the beef industry. The objective of the current study was to initiate a process of encouraging changes in the status quo, by showing how a first step in that direction might look like. Using heavy metal contents of representative beef samples from butcheries in Soroti, Uganda, typical of a sub-Saharan country, we demonstrate how relationships and common sources of metals in food could be identified in a multivariate space. Beef samples from 40 sites were analyzed by atomic absorption spectrometry for iron (Fe), zinc (Zn), nickel (Ni), chromium (Cr), lead (Pb), copper (Cu), cobalt (Co) and cadmium (Cd). The study showed that all beef samples contained these metals, the extent of which were in the order: Fe > Zn >> Ni, Cr > Pb > Cu, Co > Cd. By correlation analysis, the pairs Ni and Cr, Cd and Co, Ni and Fe or Cr and Fe were found to be most likely coming from similar sources. At least three distinct characteristics of beef consumed in Soroti were also found, a distinction perhaps arising from three major categories of feedlots used to raise donor cattle. The incremental risk of children or adults developing cancer over a lifetime was estimated and found to fall into three categories, two of which are separately explained by the presence of Cr or Ni. The sources of these metals remain a matter of speculation on our part. More studies are needed to determine these sources and to understand the nature of cancer risk in the three categories of beef identified here.

Causal influence of dietary habits on the risk of major depressive disorder: A diet-wide Mendelian randomization analysis.

BACKGROUND: Extensive observational evidence links diet quality to the risk for major depressive disorder (MDD), while clinical trials show that dietary improvement can improve depressive symptoms. However, due to issues with blinding dietary trials, confirming a causal relationship for diet's influence on MDD requires further research. Thus, we systemically investigated the bi-directional causal relationships between dietary habits and MDD by using two-sample Mendelian randomization (MR). METHODS: We collected publicly available genome-wide association studies' summary statistics for dietary habits from UK Biobank (n = 449,210) and MDD from the Psychiatric Genomics Consortium (n = 142,646). We used a weighted median approach to synthesize MR estimates across genetic instruments. For the robustness of our results, we compared weighted median results with results from the inverse-variance weighted, the weighted mode, and MR-PRESSO. RESULTS: There was moderate evidence that beef intake has a protective effect on MDD. There was weak but detectable evidence that cereal intake has a protective effect on MDD, while non-oily fish intake might increase the risk of MDD. We did not observe any causal effect of MDD on dietary habits. LIMITATIONS: Our study may suffer from the violation of assumptions of MR due to horizontal pleiotropy; therefore, we did several sensitivity analyses to detect and minimize the bias. CONCLUSIONS: In this two-sample MR analysis, we observed that higher beef intake may be protective against MDD. However, MDD did not appear to affect dietary habits. Potential mechanisms need to be further investigated to support our novel findings.

A Case-Control Study of Meat Mutagens and Colorectal Cancers in Viet Nam.

OBJECTIVE: The aim was to examine the association between heterocyclic amines 2-amino-1-methyl-6-phenylimidazo pyridine (PhIP) and the risk of colorectal cancer (CRC) in Viet Nam. METHODS: We performed a case-control study for 512 colorectal cancer patients with the histopathological confirmation and 1,096 hospital controls. We collected information on lifestyle, diet, and cooking methods from participants by trained interviewers using the validated questionnaires. We used data of PhIP concentration in cooked beef analyzed by the LC/MS/MS and cooking questionnaire to estimate the daily intake of PhIP. We divided the estimated amount of PhIP (ng/person/day) into three levels of non-intake (the reference), medium, and high to estimate the Odds ratio and 95% confidence interval (OR, 95%CI). RESULTS: The median intake of PhIP (ng/person/day) was 18ng and 102.8ng for medium and high PhIP intake, respectively. There was a significant association between PhIP intake and the risk of colorectal cancer. The adjusted OR (95%C), high intake vs. non-intake, were 4.89 (3.03, 7.89), p_trend.