The Potential Impact of Blood System on Dietary Habits and Smoking

The ‘Blood-Type’ diet advises individuals to eat according to their ABO blood group to improve their health and decrease the risk of chronic diseases. However, the food preferences of individuals with different blood groups have not been examined. The aim of our study was to investigate, in healthy regular blood donors (rBDs), the associations of smoke, alcohol, caffeine, vitamin and fat intake with their different blood groups and if ABO groups could be a potential predictor tool for disease prevention. A total of 329 volunteers were divided into four groups according to their ABO types: Group 1 (A) comprised 141 rBDs; Group 2 (B), 65 rBDs; Group 3 (O), 96 rBDs; and Group 4, 27 rBDs. Additionally, they were divided into two groups according to their rhesus types and their preferences for smoke, too. Dietary intake was assessed using 3-day food recall and the Food Processor computer program for nutrient analysis. Alcohol, caffeine, sugar and Vitamin D consumption were significantly (p < 0.05) higher in the O group. The A group presented statistically significantly (p < 0.05) greater preferences for cholesterol intake and a higher trend for smoking (25%) habits compared with all the other groups, whereas Group B preferred more fatty foods. The blood group AB appeared to be the most controlled food intake group. Regarding the rhesus comparisons, alcohol; caffeine; and Vitamin C, D, E and K consumptions were significantly (p < 0.05) higher in rhesus-positive individuals than their rhesus-negative counterparts. For the non-smoker group, compared with the smokers, a higher consumption of Vitamin D and fibers was found. In conclusion, in the present study, statistically significant correlations of the ABO and rhesus system with some dietary parameters were found, indicating a consequent influence of these preferences on the progression of different diseases.

Plant-Based Diet as a Strategy for Weight Control

According to the World Health Organization, obesity has nearly tripled since the 1970s. Obesity and overweight are major risk factors for cardiovascular diseases, diabetes, inflammatory-mediated diseases, and other serious medical conditions. Moreover, recent data suggest that obesity, overweight, diabetes, and cardiovascular diseases are risk factors for COVID-19-related mortality. Different strategies for weight control have been introduced over the last two decades. Unfortunately, these strategies have shown little effect. At the same time, many studies show that plants might be the key to a successful strategy for weight control. Following the PRISMA guidelines for conducting systematic reviews, a search was conducted in PubMed, Web of Science, Scopus, and Embase using the following keywords: obesity, globesity, vegan, plant-based diet, etc. Our results show that vegan diets are associated with improved gut microbiota symbiosis, increased insulin sensitivity, activation of peroxisome proliferator-activated receptors, and over-expression of mitochondrial uncoupling proteins. The key features of this diet are reduced calorie density and reduced cholesterol intake. The combination of these two factors is the essence of the efficiency of this approach to weight control. Our data suggest that plant-based/vegan diets might play a significant role in future strategies for reducing body weight.

Egg and Dietary Cholesterol Consumption and Mortality Among Hypertensive Patients: Results From a Population-Based Nationwide Study

Background: Hypertensive patients are sensitive to the amount of dietary cholesterol intake, especially cholesterol from the whole eggs. Whether whole egg and dietary cholesterol consumption are suitable for hypertensive patients is still controversial.Aim: The objective of the study was to examine the associations of intake of eggs as well as the dietary cholesterol with total mortality in a Chinese nationwide cohort.Methods: We utilized data from the China Health and Nutrition Survey (CHNS) from the year of 1991 to 2015. Cumulative averages of egg and cholesterol intake were calculated to represent the consumption of the long-term diet of the participants in each available round of the survey. Cox regression models were employed to estimate the effects of eggs and dietary cholesterol from the different sources on mortality among hypertensive patients.Results: A total of 8,095 participants were included in the final analysis and followed up for a mean of 11.4 years. Finally, 927 cases of death were detected. After adjustment for the multivariate factors, consuming more than seven eggs per week was related to 29% lower mortality among the hypertensive patients compared with the consumers with not more than two eggs per week [hazard ratio (HR): 0.71; 95% CI: 0.59–0.85; P &lt; 0.001]. Similarly, the egg-sourced cholesterol intake was inversely associated with mortality (P = 0.002) whereas intake of the dietary cholesterol from the non-egg sources was significantly related to the higher mortality (P &lt; 0.001). However, total cholesterol intake was not related to mortality among hypertensive patients. Substituting eggs for an equivalent amount of non-egg-sourced protein-abundant foods was also associated with lower mortality.Conclusion: Higher consumption of eggs and egg-sourced dietary cholesterol was associated with lower mortality among the enrolled Chinese hypertensive patients but non-egg-sourced cholesterol intake was related to higher mortality. Therefore, our findings do not support the view that hypertensive patients should avoid whole egg consumption for the purpose of restricting dietary cholesterol intake.

Association of Dietary Cholesterol Intake With Risk of Gastric Cancer: A Systematic Review and Meta-Analysis of Observational Studies

Background: Many case–control studies have investigated the association between dietary cholesterol and gastric cancer, yielding inconsistent findings. We carried out a systematic review and meta-analysis of observational studies to assess the relationship between dietary cholesterol intake and gastric cancer among adults.Methods: PubMed, Scopus, and Google Scholar were systematically searched to identify articles that evaluated the association of dietary cholesterol with gastric cancer up to May 2021. Pooled odds ratio (ORs) and 95% confidence intervals (CIs) were computed using random-effects models. Dose–response analysis was used to explore the shape and strength of the association.Results: Fourteen case–control studies with 6,490 gastric cancer patients and 17,793 controls met our inclusion criteria. In the meta-analysis of the highest vs. the lowest dietary cholesterol categories, a significantly higher (~35%) risk of gastric cancer was observed in association with high cholesterol consumption (pooled OR: 1.35, 95% CI: 1.29–1.62, I2 = 68%; 95%CI: 45–81%). Subgroup analysis also showed this positive relationship in population-based case–control studies, those conducted on non-US countries, those with a higher number of cases and high-quality studies, those that collected dietary data via interviews, studies not adjusted for Helicobacter pylori infection, and studies where the body mass index was controlled. Besides, a non-linear dose–response association was also identified (P = 0.03).Conclusion: This study demonstrated that dietary cholesterol intake could significantly augment the risk of gastric cancer in case–control studies. Prospective cohort studies with large sample sizes and long durations of follow-up are required to verify our results.

Cholesterol and Egg Intakes with Cardiometabolic and All-Cause Mortality among Chinese and Low-Income Black and White Americans

We examined the associations of dietary cholesterol and egg intakes with cardiometabolic and all-cause mortality among Chinese and low-income Black and White Americans. Included were 47,789 Blacks, 20,360 Whites, and 134,280 Chinese aged 40–79 years at enrollment. Multivariable Cox models with restricted cubic splines were applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality outcomes using intakes of 150 mg cholesterol/day and 1 egg/week as the references. Cholesterol intake showed a nonlinear association with increased all-cause mortality and a linear association with increased cardiometabolic mortality among Black Americans: HRs (95% CIs) associated with 300 and 600 mg/day vs. 150 mg/day were 1.07 (1.03–1.11) and 1.13 (1.05–1.21) for all-cause mortality (P-linearity = 0.04, P-nonlinearity = 0.002, and P-overall < 0.001) and 1.10 (1.03–1.16) and 1.21 (1.08–1.36) for cardiometabolic mortality (P-linearity = 0.007, P-nonlinearity = 0.07, and P-overall = 0.005). Null associations with all-cause or cardiometabolic mortality were noted for White Americans (P-linearity ≥ 0.13, P-nonlinearity ≥ 0.06, and P-overall ≥ 0.05 for both). Nonlinear inverse associations were observed among Chinese: HR (95% CI) for 300 vs. 150 mg/day was 0.94 (0.92–0.97) for all-cause mortality and 0.91 (0.87–0.95) for cardiometabolic mortality, but the inverse associations disappeared with cholesterol intake > 500 mg/day (P-linearity ≥ 0.12; P-nonlinearity ≤ 0.001; P-overall < 0.001 for both). Similarly, we observed a positive association of egg intake with all-cause mortality in Black Americans, but a null association in White Americans and a nonlinear inverse association in Chinese. In conclusion, the associations of cholesterol and egg intakes with cardiometabolic and all-cause mortality may differ across ethnicities who have different dietary patterns and cardiometabolic risk profiles. However, residual confounding remains possible.

Associations of Changes in Blood Lipid Concentrations with Changes in Dietary Cholesterol Intake in the Context of a Healthy Low-Carbohydrate Weight Loss Diet: A Secondary Analysis of the DIETFITS Trial

In 2015, the Dietary Guidelines for Americans (DGA) eliminated the historical upper limit of 300 mg of dietary cholesterol/day and shifted to a more general recommendation that cholesterol intake should be limited. The primary aim of this secondary analysis of the Diet Intervention Examining the Factors Interacting With Treatment Success (DIETFITS) weight loss diet trial was to evaluate the associations between 12-month changes in dietary cholesterol intake (mg/day) and changes in plasma lipids, particularly low-density lipoprotein (LDL) cholesterol for those following a healthy low-carbohydrate (HLC) diet. Secondary aims included examining high-density lipoprotein (HDL) cholesterol and triglycerides and changes in refined grains and added sugars. The DIETFITS trial randomized 609 healthy adults aged 18–50 years with body mass indices of 28–40 kg/m2 to an HLC or healthy low-fat (HLF) diet for 12 months. Linear regressions examined the association between 12-month change in dietary cholesterol intake and plasma lipids in 208 HLC participants with complete diet and lipid data, adjusting for potential confounding variables. Baseline dietary cholesterol intake was 322 ± 173 (mean ± SD). At 12 months, participants consumed an average of 460 ± 227 mg/day of dietary cholesterol; 76% consumed over the previously recommended limit of 300 mg/day. Twelve-month changes in cholesterol intake were not significantly associated with 12-month changes in LDL-C, HDL-C, or triglycerides. Diet recall data suggested participants’ increase in dietary cholesterol was partly due to replacing refined grains and sugars with eggs. An increase in daily dietary cholesterol intake to levels substantially above the previous 300 mg upper limit was not associated with a negative impact on lipid profiles in the setting of a healthy, low-carbohydrate weight loss diet.

Phagocytic and pinocytic uptake of cholesterol in Tetrahymena thermophila impact differently on gene regulation for sterol homeostasis

The ciliate Tetrahymena thermophila can either synthesize tetrahymanol or when available, assimilate and modify sterols from its diet. This metabolic shift is mainly driven by transcriptional regulation of genes for tetrahymanol synthesis (TS) and sterol bioconversion (SB). The mechanistic details of sterol uptake, intracellular trafficking and the associated gene expression changes are unknown. By following cholesterol incorporation over time in a conditional phagocytosis-deficient mutant, we found that although phagocytosis is the main sterol intake route, a secondary endocytic pathway exists. Different expression patterns for TS and SB genes were associated with these entry mechanisms. Squalene synthase was down-regulated by a massive cholesterol intake only attainable by phagocytosis-proficient cells, whereas C22-sterol desaturase required ten times less cholesterol and was up-regulated in both wild-type and mutant cells. These patterns are suggestive of at least two different signaling pathways. Sterol trafficking beyond phagosomes and esterification was impaired by the NPC1 inhibitor U18666A. NPC1 is a protein that mediates cholesterol export from late endosomes/lysosomes in mammalian cells. U18666A also produced a delay in the transcriptional response to cholesterol, suggesting that the regulatory signals are triggered between lysosomes and the endoplasmic reticulum. These findings could hint at partial conservation of sterol homeostasis between eukaryote lineages.