Higher dietary acid load is associated with the risk of hyperuricemia.

PURPOSE: Dietary acid load plays a key role in regulating serum uric acid levels. We hypothesized that dietary acid load indices would be positively associated with the odds of hyperuricemia. We aimed to test this hypothesis in a representative sample of Iranian adult population. METHODS: In this cross-sectional study, a total of 6145 participants aged 35-65 years were recruited from MASHAD cohort study. Dietary intakes were assessed using a 24-h dietary recall. Diet-based acid load was assessed as the potential renal acid load (PRAL), net endogenous acid production (NEAP), and dietary acid load (DAL). Hyperuricemia was defined as serum uric acid greater than the 75th percentile. Multivariable logistic regression models were applied to determine the association between diet-based acid load scores and hyperuricemia. RESULTS: The mean age of participants was 48.89 ± 8.09 years. Overall, 25.7% had hyperuricemia. According to the full-adjusted model, there was a significant association between higher tertile of PRAL, and DAL and hyperuricemia (Q3 PRAL; OR (95% CI): 1.23 (1.05-1.43), Q3 DAL; OR (95% CI): 1.22 (1.05-1.42)). Regarding NEAP, there was no significant association with hyperuricemia. We also found that dietary intake of total sugars, fiber, calcium, and magnesium was associated with the odds of hyperuricemia in our population. CONCLUSION: This study showed a significant positive association between two indicators of dietary acid load (PRAL, and DAL) and odds of hyperuricemia among Iranian adults.

Higher dietary acid load is associated with an increased risk of metabolic syndrome.

There have been inconsistent reports regarding the association between dietary acid load and Metabolic Syndrome (MetS). We aimed to investigate the association between dietary acid load and MetS in an Iranian adult population. In this cross-sectional study, 1945 participants aged 35-65 years were recruited from MASHAD cohort study. Dietary intakes were assessed using a 24-h dietary recall. Diet-based acidity was assessed as the net endogenous acid production (NEAP), potential renal acid load (PRAL), and dietary acid load (DAL). To define MetS, the International Diabetes Federation (IDF) criteria were used. Multivariable logistic regression models were applied to determine the association between diet-based acid load scores and MetS. Participants' mean age and BMI were 47.13 ± 7.78 years and 27.57 ± 4.48 kg/m2, respectively. Around 57% of the population was female. Overall, 31.9% had MetS. According to the full-adjusted model, there was a significant association between higher quartiles of PRAL, NEAP, and DAL and MetS (Q4 PRAL; OR (95%CI) 1.42(1.05-1.91), Q4 NEAP; OR (95%CI) 1.48(1.11-1.98), Q4 DAL; OR (95%CI) 1.44(1.05-1.91)). This study showed a significant positive association between different dietary acid load indicators (PRAL, NEAP, and DAL) and odds of MetS among Iranian adults.

Dietary Intakes of Choline and Betaine and Incidence of Type 2 Diabetes: Tehran Lipid and Glucose Study.

Background: Our knowledge for the possible link between choline and betaine and the risk of type 2 diabetes (T2D) is very limited and contradictory. This study aimed to investigate the prospective association of dietary choline and betaine intakes with the risk of T2D in a group of Tehranian adults. Methods: In this prospective study, 6022 eligible subjects aged ≥18 years were chosen from the participants of the Tehran Lipid and Glucose Study in a secondary analysis. Diet was assessed based on a valid and reliable semiquantitative food frequency questionnaire. At baseline and follow-up examinations, biochemical and anthropometric variables were assessed. Multivariable Cox proportional hazard regression models was used to estimate the new onset of T2D concerning choline and betaine intake. Results: The mean age ± SD of 2707 men and 3315 women were, respectively, 41.4 ± 14.2 and 39.1 ± 13.1. During a median follow-up of 6.63 years, 528 cases of T2D incidence were diagnosed. Participants with a higher intake of choline had a higher intake of protein, fiber, and B12 and a lower intake of energy and carbohydrates. After controlling of confounders a significant positive association was observed between choline intake and the hazard ratio (HR) of T2D across quartiles of choline intake [HR (CI) in the fourth quartile: 1.25 (1.14-1.38), P trend = 0.01], but this significant finding was not reported for betaine intake. For every 100 milligram increase in choline consumption, the HR of T2D increased significantly in all age, sex, and BMI subgroups. Conclusions: Choline consumption increased the risk of T2D in total population and subgroups. No statistically significant association was found between dietary betaine intake and the risk of T2D in total population and subgroups.

Dietary approach to stop hypertension and healthy eating index 2015, modify the association between FTO polymorphisms and obesity phenotypes.

This study aimed to investigate the interaction of the healthy eating index (HEI) and the dietary approach to stop hypertension (DASH) diet scores with FTO polymorphisms in relation to change in obesity traits. A total of 4480 subjects aged ≥ 18 years were selected from participants of the Tehran lipid and glucose study and followed-up 3 years. Selected polymorphisms (rs1421085, rs1121980, rs8050136) were genotyped and genetic risk score (GRS) was computed. HEI and DASH scores were computed based on dietary data. Changes in body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and visceral adiposity index (VAI) were measured. Higher adherence to both DASH and HEI scores were increased with higher ages. Individuals with high GRS had a lower change in BMI when they had higher adherence to HEI, compared to subjects with lower HEI score (P trend = 0.01). Change in WC in participants in the fourth quartile of HEI score in minor allele carriers of FTO variants was lower compared to the first quartile; conversely, higher adherence to the DASH score by this genotypic group was related to increase in WC. No significant interaction was seen between FTO polymorphisms and both diet scores regarding changes in any of obesity traits. In conclusion, in individuals with high GRS higher adherence to HEI score was associated with lower change in BMI and WC, while higher adherence to DASH diet was associated with higher change in WC, compared to individuals with lower adherence to both scores.

Diet quality and anthropometric indices of patients undergone bariatric surgery: the prospective Tehran obesity treatment study.

BACKGROUND: Patients undergone bariatric surgery (BS) has long-term risks including decrease in diet quality, nutritional deficiencies and weight regain. This study focus on assessing dietary quality and food group components in patients one year after BS, the relationship between dietary quality score and anthropometric indices, and also evaluating the trend of body mass index (BMI) of these patients three years after BS. METHODS: A total of 160 obese patients (BMI ≥ 35 kg/m2) were undergone sleeve gastrectomy (SG) (n = 108) or gastric bypass (GB) (n = 52), participated in this study. They were assessed for dietary intakes using three 24-hour dietary recalls one year after surgery. Dietary quality was assessed using food pyramid for post BS patients and healthy eating index (HEI). Anthropometric measurements were taken pre-surgery and 1, 2 and 3 years after operation. RESULTS: The mean age of patients was 39.9 ± 11 years (79% female). The mean ± SD percentage of excess weight loss was 76.6 ± 21.0 one year after surgery. Intake patterns are generally (up to 60%) not consistent with the food pyramid. The mean total HEI score was 64 ± 12 out of 100. More than %60 of participants is exceeding the recommendations for saturated fat and sodium. The HEI score did not show significant relationship with anthropometric indices. The mean of BMI in SG group increased over three years of follow up, while in GB group, there were no significant differences in BMI during three years of follow up. CONCLUSIONS: These findings showed that patients had not healthy pattern intake one year after BS. Diet quality did not show significant relationship with anthropometric indices. The trend of BMI three years after surgery was different based on surgery types.

The association between dietary acrylamide intake and the risk of type 2 diabetes incidence in the Tehran lipid and glucose study.

This study aimed at investigating the association of acrylamide consumption with the incidence of type 2 diabetes (T2D) in adults. The 6022 subjects of the Tehran lipid and glucose study participants were selected. The acrylamide content of food items were summed and computed cumulatively across follow up surveys. Multivariable Cox proportional hazard regression analyses were performed to estimate the hazards ratio (HR) and 95% confidence interval (CI) of incident T2D. This study was done on men and women, respectively aged 41.5 ± 14.1 and 39.2 ± 13.0 years. The mean ± SD of dietary acrylamide intake was 57.0 ± 46.8 µg/day. Acrylamide intake was not associated with the incidence of T2D after adjusting for confounding variables. In women, a higher acrylamide intake was positively associated with T2D [HR (CI) for Q4: 1.13 (1.01-1.27), P trend: 0.03] after adjusting for confounding factors. Our results demonstrated that dietary intake of acrylamide was associated with an increased risk of T2D in women.

Meat Food Group Intakes and the Risk of Type 2 Diabetes Incidence.

Aim: This study aimed to evaluate the association of meats and their substitute food group intakes, including nuts, eggs, and legumes, with type 2 diabetes (T2D). Methods: For this secondary analysis, we selected eligible adults (n = 6,112) from the Tehran Lipid and Glucose Study participants with a median follow-up of 6.63 years. Expert nutritionists assessed dietary intakes using a valid and reliable semiquantitative food frequency questionnaire. Biochemical and anthropometric variables were assessed at baseline and follow-up examinations. We used multivariable Cox proportional hazard regression models to estimate the new onset of T2D concerning meats and their substitute food groups. Results: We performed this study on 2,749 men and 3,363 women, aged 41.4 ± 14.2 and 39.1 ± 13.1 years, respectively. The number of participants with incident T2D was 549. After adjusting for confounders, legume [HR: 1, 0.74 (0.58-0.94), 0.69 (0.54-0.90), 0.65 (0.50-0.84), P-trend = 0.01)] was inversely associated with incident T2D. Fish intake [HR: 1, 1.0 (0.79-1.27), 1.17 (0.91-1.50), 1.14 (0.89-1.45), P-trend = 0.01)] was positively associated with incident T2D. In subjects who reported poultry consumption of 36.4-72.8 g/day, a positive association [HR: 1.33 (1.03-1.71)] between poultry intake and T2D risk was observed. Conclusion: Our findings revealed that a diet rich in legumes significantly reduced the risk of T2D incidence, while a diet high in poultry increased the risk of T2D incidence, probably due to high-temperature cooking methods and environmental contaminants.

Effective food hygiene principles and dietary intakes to reinforce the immune system for prevention of COVID-19: a systematic review.

BACKGROUND: This study aimed at reviewing effective food hygiene principles and dietary intakes to reinforce the immune system for prevention of corona virus disease 2019 (COVID-19). METHODS: The systematic literature search was performed in three databases from Jan. 2020 up to 10th July 2020. English articles that focused on nutrition, food, immunity and corona virus were searched. Systematic and narrative reviews were included. RESULTS: After evaluation of search papers, 27 relevant articles were used in this review. The importance of nutrients, phytochemicals, probiotics and some spices were highlighted for enhancing immunity during the COVID-19 pandemic. A healthy dietary pattern with proper energy intake provides sufficient nutrients. The unhealthy dietary pattern is linked with inflammation and risk factors related to high mortality in patients with severe COVID-19 infection. Different thermal procedures have been used for the inactivation of viruses. It is recommended not to consume raw or undercooked animal products. CONCLUSIONS: It is critical to ensure that the nutritional needs of the population are met and sustained based on standards during a COVID-19 pandemic. Clear advice on adequate calorie intake and an optimal healthy diet to support the immune function should be provided. Good hygiene practices must be performed by everyone and done in the food industry.

Association of Coffee and Caffeine Intake With Irritable Bowel Syndrome in Adults.

The aim of this study was to investigate the association between coffee and caffeine intake and odds of IBS and its severity in adult population. In this cross-sectional study, dietary intakes of 3,362 Iranian adults were examined using a validated dish-based 106-item Semi-quantitative Food Frequency Questionnaire (DS-FFQ). Coffee and caffeine intake was assessed using the DS-FFQ. IBS was assessed using a modified Persian version of Rome III questionnaire. After adjustment for potential confounders, we found that individuals who were taking coffee weekly or more had greater odds of IBS (OR:1.44; 95% CI: 1.02-2.04) than those who never drinking coffee. In addition, participants in the top tertile of caffeine intake (≥106.5 mg/d) had 47% greater odds of IBS compared to those in the bottom tertile (<69.4 mg/d) (OR: 1.47; 95% CI: 1.14-1.87). By gender, a significant association was observed between caffeine intake and odds of IBS among women (OR for those in the highest tertile vs. lowest tertile: 1.48; 95% CI: 1.10-2.00), but not in men (OR: 1.47; 95% CI: 0.94-2.30). In addition, a significant positive association was seen between caffeine intake and odds of IBS among subjects with BMI ≥ 25 kg/m2 (OR for those in the highest tertile vs. lowest tertile: 1.72; 95% CI: 1.20-2.48). There was a significant association between caffeine intake and IBS severity among subjects with BMI ≥ 25 kg/m2 (OR: 1.04; 95% CI: 1.01-2.62). In conclusion, coffee and caffeine consumption was associated with increased odds of IBS in the whole study population. The association between caffeine and odds of IBS was also significantly positive among women and overweight or obese subjects (BMI ≥ 25 kg/m2). In addition, we found a significant relationship between caffeine intake and severity of IBS symptoms among overweight or obese subjects (BMI ≥ 25 kg/m2).

Dietary intake of branched-chain amino acids in relation to depression, anxiety and psychological distress.

BACKGROUND: There is no previous study that examined the association between branched-chain amino acids (BCAAs) intake and odds of psychological disorders. The aim of this study was to investigate the association between dietary BCAAs and odds of psychological disorders including depression, anxiety, and psychological distress in a large sample of Iranian adults. METHODS: In this cross-sectional study on 3175 Iranian adults aged 18-55 years, a validated food frequency questionnaire was used to assess dietary intakes. BCAAs intake was computed by summing up the amount of valine, leucine, and isoleucine intake from all food items in the questionnaire. Psychological health was examined through the use of Iranian validated version of the Hospital Anxiety and Depression Scale (HADS). Psychological distress was assessed using General Health Questionnaire (GHQ). For depression and anxiety, scores of 8 or more on either subscale were considered as psychological disorders and scores of 0-7 were defined as "normal". In terms of psychological distress, the score of 4 or more was defined as psychological distress. RESULTS: Mean age of study participants was 36.2 ± 7.8 years. Overall, 26.4% (n = 837) of study subjects had depression, 11.9% (n = 378) had anxiety and 20.9% (n = 665) were affected by psychological distress. After controlling for potential confounders, participants in the highest tertile of total BCAAs intake had lower odds of depression (OR: 0.76; 95% CI: 0.60-0.96) and anxiety (OR: 0.66; 95% CI: 0.47-0.91) compared with those in the lowest tertile. Participants in the top tertile of valine intake had a lower odds of depression (OR: 0.76; 95% CI: 0.60-0.96) and anxiety (OR: 0.65; 95% CI: 0.47-0.90) compared with those in the bottom tertile. A significant inverse association was also seen between leucine intake and depression (OR: 0.77; 95% CI: 0.61-0.98) and anxiety (OR: 0.66; 95% CI: 0.47-0.91). In addition, a significant inverse association was observed between isoleucine intake and odds of depression (OR: 0.75; 95% CI: 0.59-0.95) and anxiety (OR: 0.62; 95% CI: 0.45-0.86). There was no significant association between isoleucine intake and odds of psychological distress. CONCLUSION: Evidence indicating an inverse association between dietary intake of BCAAs and odds of depression and anxiety was found. Prospective studies are required to confirm these findings.

The association of dietary macronutrients composition with the incidence of cardiovascular disease, using iso-energetic substitution models: Tehran lipid and glucose study.

BACKGROUND AND AIMS: Dietary macronutrient composition plays an important role in the prevention of cardiovascular disease (CVD). This study aimed at assessing the iso-energetic substitution of dietary macronutrients in relation to the incidence of CVD. MATERIALS AND RESULTS: This prospective study was conducted on 5102 individuals of Tehran lipid and glucose study participants, aged 20-70 years who were followed for 5.3 years. A valid and reliable semi-quantitative food frequency questionnaire was used to assess dietary intakes. The hazard ratio of CVD for each 5% of energy from macronutrients at the expense of another macronutrient was calculated using the substitution model. During follow-up, a total of 206 CVD outcomes were identified. Mean age of participants (44.2% men) was 47.0 ± 12 and 45.6 ± 11 for men and women, respectively. Substituting 5% of energy from all types of macronutrients by 5% percentage of energy from combined saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) was associated with a decrease in the risk of CVD by almost 20%. Higher energy intake from total-, starchy-, and nonstarchy carbohydrates replaced by other macronutrients was not significantly associated with the risk of CVD. Each 5% of energy from animal protein (HR: 1.09 and CI: 1.02-1.16) independently increased the risk of CVD in the adjusted Cox proportional hazard regression analyses. CONCLUSION: Higher percentage of energy from animal protein independently increased the risk of CVD, replacement of SFA and MUFA together with other macronutrients was inversely associated with CVD risk.

The association of dietary macronutrients with anthropometric changes, using iso-energetic substitution models: Tehran lipid and glucose study.

BACKGROUND: The consequences of optimal dietary macronutrient compositions especially quality of proteins on weight gain still remain controversial. The aim of the current study was to evaluate the iso-energetic substitution of dietary macronutrients in relation to anthropometric changes. METHODS: This prospective study was conducted on 2999 men and 4001 women aged 20-70 years who were followed for 3.6 years. A valid and reliable 168-item semi-quantitative food frequency questionnaire was used to assess usual dietary intakes. Weight (kg) and waist circumference (WC) (cm) changes were calculated by subtracting the weight and WC at baseline from their measurements at follow up. Participants were divided into two groups; those with no change or decrease in weight or WC and those with increase in weight or WC. Dietary macronutrients (percentage of energy) divided by 5 to calculate one unit. RESULTS: A one unit higher proportion of carbohydrates at the expense of all types of fatty acids was associated with weight loss in men (P < 0.05). A one unit higher proportion of plant proteins at the expense of animal protein (ß = - 0.84), non-starch carbohydrates (ß = - 0.86), saturated fat (ß = - 0.76), mono-unsaturated fat (ß = - 0.76) and poly-unsaturated fat (ß = - 0.86) was associated with weight loss (P < 0.05). A one unit higher proportion of plant proteins at the expense of animal proteins (OR: 0.49), non-starch carbohydrates (OR: 0.49), saturated fat (OR: 0.49), mono-unsaturated fat (OR: 0.49), and poly-unsaturated fat (OR: 0.48) was associated with a lower risk of increase in WC (P < 0.05). CONCLUSIONS: A higher proportion of dietary plant protein in replacement of simple carbohydrates, fats and animal proteins was associated with a lower increase in weight or WC.

Dietary patterns modify the association between fat mass and obesity-associated genetic variants and changes in obesity phenotypes.

The present study investigated whether dietary patterns could interact with fat mass and obesity-associated (FTO) polymorphisms in relation to changes in BMI and waist circumference (WC) over 3⋅6 years of follow-up. Subjects were selected from participants of the Tehran Lipid and Glucose Study (n 4292, 43⋅2 % male). Dietary data were collected using a valid and reliable FFQ. Dietary patterns were determined using factor analysis. The genotypes of polymorphisms (rs1421085, rs1121980, rs17817449, rs8050136, rs9939973 and rs3751812) were determined. Genetic risk score (GRS) was calculated using the weighted method. Mean ages of men and women were 42·6 (sd 14) and 40⋅4 (sd 13) years, respectively. The healthy (e.g. vegetables and fruits) and the Western dietary patterns (WDP; e.g. soft drinks and fast foods) were extracted. In carriers of the risk alleles rs1121980, rs1421085, rs8050136, rs1781799 and rs3751812, BMI was approximately 2-fold higher in individuals in the higher quartile of WDP score, compared with the first quartile (P < 0⋅05). WC increased with increasing WDP score in carriers of the risk alleles rs1121980 and rs3751812, but not in individuals who did not carry any risk alleles. BMI and WC increased to a greater extent in the high GRS group while increasing quartiles of the WDP score, compared with the low GRS group (BMI change; Q1: 1⋅04 (se 0⋅34) v. Q4: 2⋅26 (se 0⋅36)) (WC change; Q1: 0⋅47 (se 0⋅32) v. Q4: 0⋅95 (se 0⋅34)) (P interaction < 0⋅05). These results suggest that adults with higher genetic predisposition to obesity are more susceptible to the harmful effects of adherence to the WDP, which emphasised the need to reduce the consumption of unhealthy foods for the prevention of obesity.