Associations between diet and nutritional supplements and colorectal cancer: A systematic review.

Background and Aim: Colorectal cancer (CRC) is one of the most prevalent cancers around the world. The link between nutrients and the likelihood of developing CRC remains uncertain. The primary objective of the present study was to investigate the potential connection between dietary intake/dietary supplements and the occurrence of CRC through a literature review. Methods: A comprehensive online search was conducted in PubMed, Scopus, Web of Science, and the Cochrane Library from January 1990 to March 2023 using appropriate keywords. A systematic search was conducted for clinical trials and cohort studies in order to determine the relationship between dietary components/supplements and CRC. Results: The intake of long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFAs), consisting of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has the potential to decrease the likelihood of developing CRC (eight studies found positive effects and four studies found no association). Some other dietary components such as probiotics, prebiotics, and synbiotics may contribute to suppressing CRC development (three studies found positive effects, whereas three studies did not find any association). There is inconclusive evidence that supplementation with certain micronutrients including vitamin D (one trial found positive effects and another trial reported no association), folate, zinc, and selenium may reduce the risk of CRC. Conclusion: Some dietary supplements such as n-3 LCPUFAs and probiotics have the potential to reduce the risk of developing CRC. Further studies are necessary to validate these results and understand the underlying mechanisms.

A systematic review of the beneficial effects of prebiotics, probiotics, and synbiotics on ADHD.

BACKGROUND: Children with attention deficit hyperactivity disorder (ADHD) may benefit from probiotics and prebiotics, but the effects are unclear. To determine whether probiotics and prebiotics affect children with ADHD, a systematic review was conducted. METHODS: The present systematic review analyzed cohort studies and randomized controlled trials that examined whether prebiotics and probiotics are associated with ADHD. Seven randomized controlled trials and two cohort studies met our inclusion criteria. RESULTS: Research on Lactobacillus rhamnosus GG (LGG) probiotic supplementation showed that children with ADHD had better emotional, physical, social, and school functioning, and a higher health-related quality of life compared to the placebo group. The studies also showed that Synbiotic 2000 reduces markers of intestinal and vascular inflammation in children with ADHD, in part through increasing SCFA levels. CONCLUSION: The use of probiotics and prebiotics as adjuvants therapy in patients with ADHD is beneficial. Further studies with longer duration, including more participants and a variety of age groups, and using various evaluation techniques such as in vivo observation are required to examine the effects of prebiotics and probiotics on ADHD.

The effects of omega-3 fatty acids supplementation on hemoglobin, hematocrit, and platelet levels of patients with ESRD condition undergoing dialysis.

Background: Concomitant inflammation may boost the cardiovascular complications in end-stage renal disease (ESRD) patients undergoing hemodialysis (HD). Omega-3 fatty acids may have certain health benefits in HD patients. The aim of this study was to investigate the effects of omega-3 fatty acids supplementation on hematocrit (HCT), hemoglobin (HB) level and platelet (PLT) counts of HD patients. Methods: A randomized controlled trial was conducted on HD patients at a private dialysis center in Rasht, Iran. Three omega-3 fatty acid supplement capsules (3 g/d) were administered daily for two months to patients in the intervention group (n = 55). The control group (n = 60) were given three placebo capsules containing medium chain triglyceride (MCT) oil, similar to the supplemental dose of the intervention group at the same period. Three parameters of HCT, HB and PLT were measured at baseline and after the intervention. Results: The PLT count decreased in the intervention group compared to the control group (173.38 ± 74.76 vs. 227.68 ± 86.58 103/mm3, F = 4.83, P = 0.03). No significant change was found on the levels of HCT and HB parameters between the two groups after the intervention. Conclusion: Omega-3 supplementation in HD patients may decrease the risk of forming blood clots in the blood vessels. Further studies are warranted.

Effectiveness of omega-3 fatty acid supplementation for pruritus in patients undergoing hemodialysis.

Background: Patients undergoing hemodialysis (HD) frequently experience the chronic kidney disease-associated pruritus (CKD-aP). Objective: The aim of this study was to investigate the effectiveness of omega-3 supplementation in the management of CKD-aP in patients undergoing hemodialysis. Methods: In this triple blind, randomized clinical trial, the effect of the omega-3 supplement on uremic CKD-aP was assessed in 112 chronic hemodialysis patients at Caspian Hemodialysis Center in Rasht, Iran. Patients were randomly divided into the intervention group receiving omega-3 supplements (3 g/day) and the control group receiving placebo containing MCT oil for 2 months. Results: Omega-3 supplementation had no effect on CKD-aP. The results did not change after adjusting for age and sex, additional adjustments for weight, height, physical activity, smoking, and alcohol use, additional adjustments for underlying diseases and weight, height, physical activity, smoking, and drinking alcohol, and further adjustments for underlying diseases and biochemical indices. Discussion: Omega-3 supplementation for 2 months had no effect on CKD-aP in patients with CKD. Further studies with longer duration are warranted. Clinical Trial Registration: https://www.irct.ir/trial/66638, IRCT20151226025699N6.

Association between type 2 diabetes and different types of dietary fats: A case-control study.

BACKGROUND: The effect of dietary fats on type 2 diabetes (T2D) is not clear. This study aimed to determine the association between T2D and dietary fatty acids among Iranian adults. METHODS: This case-control study was performed on 4241 participants aged 35-70, including 1804 people with T2D and pre-diabetes as the case group and 2437 people without diabetes as the control group. Dietary intake was assessed using a food frequency questionnaire (FFQ). RESULTS: The cases had higher age (48.36 ± 8.62 vs. 54.53 ± 7.75 y, P < 0.001), weight (73.7713.41 vs. 76.18 ± 13.49 kg, P = 0.001), body mass index (BMI) (28.02 ± 4.70 vs. 24 ± 4.74 kg/m2, P = 0.001), right systolic blood pressure (RSBP) (113.33 ± 16.7 vs. 121.61 ± 17.24 mmHg, P = 0.001), right diastolic blood pressure (RDBP) (71.41 ± 10.53 vs. 75.33 ± 9.92 mmHg, P = 0.001), fasting blood sugar (FBS) (96.87 ± 19.39 vs. 169.95 ± 69.28 mg/dl, P = 0.001), blood urine nitrogen (BUN) (13.65 ± 3.74 vs. 14.26 ± 4.03 mg/dl, P = 0.001), triglyceride (TG) (141.61 ± 99.37 vs. 175.96 ± 114.74 mg/dl, P = 0.001), alkaline phosphatase (ALP) (218.24 ± 66.35 vs. 246.97 ± 72.65 IU/L, P = 0.001), low-density lipoprotein cholesterol (LDL) (111.68 ± 33.02 vs. 101.97 ± 36.54 mg/dl, P = 0.001), serum glutamic-pyruvic transaminase (SGPT) (21.88 ± 15.15 vs. 23.55 ± 15.96 IU/L, P = 0.001), gamma-glutamyl transferase (GGT) (24.66 ± 20.42 vs. 30.72 ± 30.43 IU/L P = 0.001), and cholesterol (192.45 ± 39.1190 vs. 187.12 ± 46.19 mg/dl P = 0.001) compared to the control group. T2D was negatively associated with dietary intake of PUFAs (OR = 0.93, CI95%:0.84-1.03, P = 0.01) and positively associated with dietary cholesterol (OR: 1.01, CI95%:1.001-1.01, P = 0.02). CONCLUSION: In summary, cholesterol was positively and PUFAs were negatively associated with diabetes. If the results of the present study on the effect of fat intake on diabetes are proven, future dietary recommendations for people at risk of diabetes may be corrected by providing diets rich in polyunsaturated fatty acids and low in cholesterol.

Female infertility and dietary antioxidant index (DAI); a case-control study.

BACKGROUND: Adequate intake of natural antioxidants may improve female fertility. The aim of this study was to examine the link between female infertility and dietary antioxidant index (DAI). METHODS: This case-control study was conducted on 125 women with recently diagnosis of reduced ovarian reserves (AMH < 1.1) as the case group and 125 women with normal ovarian reserve as the control group in Rasht, Iran. The amount of food intake was assessed using the food frequency questionnaire (FFQ) and the DAI was calculated to estimate the antioxidant capacity of the diet. RESULTS: Regarding dietary intake, the infertile women had a lower intake of potassium (2789.25 ± 777 vs. 2593.68 ± 443 mg/d, P = 0.02), magnesium (204.12 ± 66 vs. 189.73 ± 34 mg/d, P = 0.03), copper (0.93 ± 0.40 vs. 0.82 ± 0.20 mg/d, P < 0.01), vitamin C (133.99 ± 46 vs. 122.62 ± 24 mg/d, P = 0.02), and fiber (14.53 ± 3 vs. 13.44 ± 2 g/d, P < 0.05), and a higher intake of cholesterol (205.61 ± 58 vs. 227.02 ± 46 mg/d, P < 0.01) than the control group (All P < 0.05). The DAI was negatively associated with infertility (OR: 0.94, CI 95%: 0.88-0.97, P = 0.03). The association remained significant after adjustments for age, BMI, the underlying diseases, fertility frequency, IVF failure, and calorie intake. CONCLUSION: Following an antioxidant-rich diet may reduce the risk of infertility. More longitudinal studies are warranted to confirm these results and discover the underlying mechanisms.

Association of nonalcoholic fatty liver disease with the different types of dietary carbohydrates: a cross-sectional study.

Background: Many factors like sedentary lifestyle, metabolic syndrome, and obesity are involved in the increased prevalence of nonalcoholic fatty liver disease (NAFLD). Dietary consumption of carbohydrates may has a role in the risk of NAFLD. This study aimed to investigate the association of NAFLD with the different types of dietary carbohydrates. Methods: This cross-sectional study was carried out on 4200 participants including 660 patients with NAFLD and 3540 helathy individuals without NAFLD ages 35 to 70 in sabzevar, Iran. Data on socio-deomgraphic status, anthropomrtric measurments, blood tests, and dietary intake of different types of dietary carbohydrates was collected. Results: The patients with NAFLD had a significantly higher dietary intake of glucose (29.38 ± 18.29 vs. 27.42 ± 15.96 g/d, P = 0.01) and fructose (33.99 ± 20.19 vs. 31.95 ± 18.34 g/d, P = 0.01) compared to the healthy people. A positive association was observed between NAFLD with the total intake of carbohydrates after adjustment for age, sex, and BMI (OR: 1.001, CI 95%: 1-1.002, P = 0.04) The association remained significant after further adjustments for for education level, marital status, physical activity, smoking, and drinking alcohol (Model 2) and after additional adjustments for calorie intake (Model 3). Conclusions: This study showed a positive association between total dietary carbohydrate and NAFLD. In particular, the amount of dietary of carbohydrates (regardless of the type of carbohydrate) may worsen NAFLD. Further longitudinal studies are warranted.

Association between type 2 diabetes and branched chain amino acids (BCAA); a case-control study.

Background: Several amino acids and their derivatives have been implicated in insulin resistance (IR) and Type 2 Diabetes Mellitus (T2DM). This research sought to establish a relationship between the dietary levels of branched-chain amino acids (BCAA) and the risk of T2DM. Methods: This case-control study was carried out on 4200 participants consisting of 589 people with T2DM and 3611 non-diabetic aged 35 to 70 years residents in Sabzevar, Iran. Data on the economic-social, employment status, medical history, lifestyle, and sleep habits were collected via interview. The food frequency questionnaire (FFQ) was used to check the nutritional status. Participants' dietary BCAA consumption was estimated using Nutritionist IV software. Results: A significant negative association between the incidence of T2DM and the dietary levels of BCAAs after adjustment for age and sex (OR = 0.972, CI 95%:0.648-0.996, P = 0.022). The negative association remained significant after additional adjustments for body mass index (BMI) and physical activity (OR = 0.967, CI 95%: 0.943-0.992, P = 0.010). Interestingly, a positive association was found between T2DM and total BCAAs (OR = 1.067, CI 95%: 1.017-1.119, P = 0.008), Isoleucine (OR = 1.248, CI 95%: 1.043-1.494, P = 0.016), Leucine (OR = 1.165, CI 95%: 1.046-1.299, P = 0.006) and Valine (OR = 1.274, CI 95%: 1.088-1.492, P = 0.003) after further adjustment for calorie intake. Conclusions: Our results demonstrate branched-chain amino acids (BCAAs) including isoleucine, leucine, and valine are negatively associated with the incidence of type 2 diabetes (T2DM) after adjusting for age and sex, BMI, and physical activity. However, adjusting for calorie intake reversed the association between T2DM and BCAAs. These findings suggest that the association between BCAAs and T2DM may be influenced by calorie intake. Future longitudinal studies are warranted. Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-023-01247-9.

Role of rs9939506 polymorphism of FTO gene in resistance to eating in male adolescents.

BACKGROUND: Single Nucleotide Polymorphisms (SNPs) of the Fat mass and obesity-associated (FTO) gene may be associated with obesity by regulating appetite. The present study aimed to investigate the relationship between FTO genotype and resistance to eating in male adolescents. METHODS: The present cross-sectional study included 246 adolescent boys in Tehran, Iran, who were assessed for self-efficacy related to weight control using the Weight Efficacy Lifestyle (WEL), questionnaire, food intake using the Food Frequency Questionnaire (FFQ), physical activity using the International Physical Activity Questionnaire (IPAQ), and anthropometric indices using Bio-Impedance Analyzer (BIA). Moreover, the participants underwent genotyping for the rs9930506 polymorphism of the FTO gene, and the relationship between FTO genotype and resistance to eating was investigated using different models of multiple linear regression. RESULTS: According to our findings, there was a significant reverse relationship between the FTO rs9930506 genotype and resistance to eating (ß: -0.16, P = 0.01). Moreover, the relationship was still significant after adjusting for age, nutritional knowledge, BMI, and mother's BMI, educational level, and occupational status. CONCLUSION: According to our results, the FTO genotype had a significant effect on resistance to eating and food desires. However, there is a need for further studies to evaluate the underlying mechanisms of the effects of the FTO gene on appetite and obesity.

The association of dietary antioxidant index (DAI) with breast cancer among Iranian women.

Recent studies have reported that dietary antioxidants can influence the risk of breast cancer (BC). Therefore, this study aimed to investigate the association of dietary antioxidant index (DAI) with BC among Iranian women. This case-control study was conducted on 180 women with breast cancer and 360 healthy women who were referred to the cancer clinic of Shohadaye Tajrish Hospital in Tehran, Iran. A 168-item validated food frequency questionnaire (FFQ) was used to assess dietary intake. The DAI score was calculated based on the intake of antioxidant vitamins and minerals derived from the FFQ. The control group had a significantly higher intake of vitamin D (1.79±1.56 vs. 1.05±0.84 µg/d; P=0.01) and lower intake of calorie (2315±1066 vs. 2737±925 kcal/d; P=0.01), carbohydrate (311±170 vs. 402±124 g/d; P=0.01), iron (15.4±12.1 vs. 19.7±6.4 mg/d; P=0.01), thiamine (1.5±0.7 vs. 2.3±0.9 mg/d; P=0.01), niacin (18.2±9.2 vs. 24.3±7.9 mg/d; P=0.01), folic acid (465±308.7 vs. 673±205.2 µg/d; P=0.01), and selenium (82.6±41.7 vs. 98.7±40.8 µg/d; P=0.01) compared to the case group. No significant association was found between DAI with breast cancer after adjustments for age. DAI had a negative association with breast cancer after additional adjustments for BMI, the number of pregnancies, duration of breastfeeding, menopause age, and total energy intake (OR: 0.91, 95% CI: 0.90-.93, and all P<0.001). The present study identified a negative association between DAI and the risk of BC, indicating the importance of antioxidants in preventing BC. Longitudinal studies should be conducted to confirm this association.

The status of clinical nutrition in hospitals of Guilan province, Iran - A mixed-method study.

Introduction: Background: nutritional therapy has an important role in the development of medical care services, and quantitative and qualitative assessments of the status of clinical nutrition in hospitals is crucial. This study aimed to explore the current status of clinical nutrition in hospitals of Guilan province, Iran. Methods: this quantitative-qualitative (mixed method) study was performed on public hospitals in Guilan province, Iran (n = 26). The required information was collected by visiting the hospitals and interviewing with hospital dietitians. The data collection tool had two quantitative and qualitative subscales. The quantitative subscale included a 21-item checklist containing information about the referral system, cooperation of hospital staff in clinical nutrition, clinical nutrition staff status, enteral nutrition, and parenteral nutrition. Results: in more than 55 % of hospitals the patients were not adequately referred to a dietitian. In about 31.2 % of hospitals, cooperation of other departments in the field of clinical nutrition was insufficient. In 37 % of hospitals with intensive care unit (ICU), enteral nutrition was not provided properly. Only 27 % of the hospital properly provided parenteral nutrition for their patients. The most important problems mentioned by hospital dietitians included noncompliance of the food services employers with recommended diets, insufficient number of hospital dietitians, and lack of per case payment method for dietitians. Coverage of diet services by health insurance was the most common suggestion of dietitians to promote diet therapy in public hospitals. Conclusion: the situation of providing nutritional services to patients in public hospitals is not favorable in terms of quantity and quality in Guilan province, Iran. Designing the necessary policies and reorient the clinical nutrition system in hospitals to promote patients' health and accelerate patient recovery is warranted.

Introducción: Antecedentes: la terapia nutricional tiene un papel importante en el desarrollo de los servicios de atención médica, y las evaluaciones cuantitativas y cualitativas del estado de la nutrición clínica en los hospitales son cruciales. Este estudio tuvo como objetivo explorar el estado actual de la nutrición clínica en los hospitales de la provincia de Guilan, Irán. Métodos: este estudio cuantitativo-cualitativo (método mixto) se realizó en hospitales públicos de la provincia de Guilan, Irán (n = 26). La información requerida se recopiló visitando los hospitales y entrevistando a los dietistas de los hospitales. La herramienta de recolección de datos tenía dos subescalas, cuantitativa y cualitativa. La subescala cuantitativa incluía una lista de verificación de 21 ítems que contenía información sobre el sistema de derivación, la cooperación del personal del hospital en nutrición clínica, el estado del personal de nutrición clínica, la nutrición enteral y la nutrición parenteral. Resultados: en más del 40 % de los hospitales, los pacientes no fueron derivados adecuadamente a un dietista. En el 35 % de los hospitales, la cooperación de otros departamentos en el campo de la nutrición clínica fue insuficiente. En el 55 % de los hospitales con unidad de cuidados intensivos (UCI), la nutrición enteral no se brindó adecuadamente. Ninguno de los hospitales proporcionó nutrición parenteral adecuada para los pacientes. Los problemas más importantes mencionados por los dietistas hospitalarios incluyeron el incumplimiento de los programas de alimentos por parte del empleador del sector alimentario, un número insuficiente de dietistas hospitalarios y la falta de pago de honorarios de consulta a los dietistas. La cobertura de los servicios de dietética por parte del seguro de salud fue la sugerencia más común de los dietistas para promover la dietoterapia en los hospitales. Conclusión: la situación de la prestación de servicios nutricionales a pacientes en hospitales públicos no es favorable en términos de cantidad y calidad en la provincia de Guilan, Irán. Se justifica diseñar las políticas necesarias para reorientar el sistema de nutrición clínica en los hospitales y, en definitiva, promover la salud y acelerar la recuperación de los pacientes.

The association between obesity with serum levels of liver enzymes, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and gamma-glutamyl transferase in adult women.

BACKGROUND: Obesity-induced inflammation may independently disturb the function of critical organs such as liver. This study aimed to investigate the association of obesity with serum levels of biomarkers of liver function including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) in adult women. METHODS: This cross-sectional study was carried out on 360 adult women in the summer of 2020 in Tehran, Iran. The participants were categorized into two groups based on their body mass index (BMI≤29.9 and BMI > 30). The serum levels of ALT, AST, ALP and GGT were measured. Logistic regression method was used to assess the association between BMI and liver enzymes after adjusting for the confounders. RESULTS: The mean BMI in non-obese and obese groups was 26.32 ± 2.61 and 33.40 ± 2.80 kg/m2 , respectively (p = .01). A significant association was found between BMI with ALT (ß = .16, p = .002) and GGT (ß = .19, p = .01) enzymes after adjustment for age. The association between BMI and GGT remained significant after further adjustments for smoking, alcohol use, physical activity and educational status. There was no significant association between BMI and liver enzymes after adjustment for dietary intake. CONCLUSIONS: Obesity was associated with the level of serum liver enzymes. However, adjustment for dietary intake disappeared the significant results. Further studies are needed to determine the independent effects of obesity on the liver function.

Interactions of Colorectal Cancer, Dietary Fats, and Polymorphisms of Arachidonate Lipoxygenase and Cyclooxygenase Genes: A Literature Review.

Objective: Genetics and dietary factors play important roles in the development of colorectal cancer (CRC). However, the underlying mechanisms of the interactions between CRC, gene polymorphisms, and dietary fat are unclear. This review study investigated the effects of polymorphisms of arachidonate lipoxygenase (ALOX) and cyclooxygenase (COX) genes in the association between CRC and dietary fat. Methods: All the related papers published from 2000 to 2022 were collected from different databases such as PubMed, Science Direct, Scopus, and Cochran using related keywords such as colorectal cancer, ALOX, COX, polymorphism, and dietary fat. Non-English and unrelated documents were excluded. Results: Some single-nucleotide polymorphisms (SNPs) in the ALOX and COX genes, such as rs2228065, rs6413416, and rs4986832 in the ALOX gene, and rs689465 in the COX gene may play significant roles in the association between the risk of CRC and dietary fats. SNPs of ALOX and COX genes may influence the effects of dietary fatty acids on the risk of CRC. Conclusion: Some polymorphisms of the ALOX and COX genes may have important roles in the effects of dietary fat on the risk of CRC. If future studies confirm these results, dietary recommendations for preventing colorectal cancer may be personalized based on the genotype of the ALOX and COX genes.

The Association Between Fasting Blood Sugar and Index of Nutritional Quality in Adult Women.

Aim: It's unclear whether diet quality affects glycemic management. The index of nutritional quality (INQ) can examine diets both quantitatively and qualitatively (INQ). Hence, this study aimed to determine whether INQ and fasting blood sugar (FBS) are related among Iranian women. Methods: This cross-sectional study was conducted on 360 adult Iranian women. Data were collected on the participants' general characteristics, medical history, anthropometric indices, physical activity, and dietary intake. For nutrient intake assessment, a valid food frequency questionnaire (FFQ) was used, and INQ was then calculated using the daily nutrient intake. Results: After adjusting for age, FBS was significantly inverse associated with INQ for vitamins A (B = -0.193, p < 0.01), magnesium (B = -0.137, p < 0.01), phosphor (B = -0.175, p < 0.01), zinc (B = -0.113, p < 0.01), vitamin K (B = -0.197, p < 0.01), manganese (B = -0.111, p < 0.01) and selenium (B = -0.123, p < 0.01). The association between FBS and INQ for Se and Mn was disappeared after further adjustment for gender, body mass index (BMI), menopausal status, and total energy intake. Conclusion: There was a significant inverse relationship between FBS and the INQ of vitamin A, manganese, phosphor, zinc, vitamin K, magnesium, and selenium. Prospective cohort studies should be conducted to establish a causal relationship between FBS and INQ.

Breast cancer and dietary fat quality indices in Iranian women: A case-control study.

Background: The association between breast cancer (BC) and different indices of dietary fats has not been well-studied. Thus, this study aimed to investigate the association between BC and dietary fat quality (DFQ) indices in Iranian women. Methods: This case-control study was conducted on 120 women with breast cancer and 240 healthy women in Tehran, Iran. Food Frequency Questionnaire and nutritionist IV software were used to assess the intake of dietary fats and to calculate the DFQ indices. Results: The patients with BC had a higher total fat (TF) (P < 0.01) and a lower ratio of polyunsaturated fatty acids (PUFAs) omega-3 to PUFAs omega-6 (ω-3/ω-6) compared with the controls (P < 0.001). TF had a significant association with BC risk (OR: 1.16; 95% CI: 1.01-1.33, P < 0.001). No significant association was found between BC and PUFA/saturated fatty acid ratio or the ω-3/ω-6 ratio. Conclusion: The patients with BC had a lower ω-3/ω-6 ratio and a higher total dietary fat intake than the healthy women. Total dietary fat intake was also directly associated with the risk of BC. Thus, low-fat diets may have beneficial effects for BC prevention. Further longitudinal studies are warranted.