BACKGROUND:Chlorination is a widespread method for drinking water disinfection that has the drawback of introducing potentially carcinogenic chemical by-products to drinking water. OBJECTIVE:We systematically evaluated the epidemiologic evidence of exposure to trihalomethane (THM) disinfection by-products and risk of cancer. METHODS:We conducted a systematic review and meta-analysis of epidemiologic studies that assessed the association of exposure to residential concentrations of THMs with risk of cancer in adults. A protocol was preregistered in PROSPERO (CRD42023435491). PubMed, Embase, Web of Science, and Cochrane were searched for publications up to April 2024. Study selection and risk of bias appraisal using the National Toxicology Program Office of Health Assessment and Translation (NTP OHAT) tool was done in duplicate. Summary risk estimates were assessed using random effects meta-analysis and one-stage dose-response meta-analysis. RESULTS:The literature search resulted in 2,022 records, of which 29 publications assessing 14 different cancers were eligible for inclusion. Summary relative risks (RRs) were estimated for bladder cancer and colorectal cancer based on 5,860 and 9,262 cases and 84,371 and 90,272 participants, respectively. The summary RR of bladder cancer for the highest exposed compared with the lowest was 1.33 (95% CI: 1.04, 1.71), and in the dose-response analysis, RRs were statistically significant above THM concentrations of 41μg/L. For colorectal cancer, the summary RR was 1.15 (95% CI: 1.07, 1.24). CONCLUSION:According to the World Cancer Research Fund criteria, we found limited-suggestive evidence that THM in drinking water increases the risk of bladder and colorectal cancer at levels below current regulatory limits in the US and EU, indicating that these fail to protect against cancer in the general population. https://doi.org/10.1289/EHP14505.
Background:Antibodies against phosphorylcholine (anti-PC) have been reported as associated with protection against atherosclerosis, cardiovascular disease (CVD), and other chronic inflammatory diseases. Underlying potential mechanisms have been demonstrated and include anti-inflammatory, clearance of dead cells, and inhibition of oxidized low-density lipoprotein effects. Objectives:This study examined the role of IgM anti-PC and incident CVD among women, where less is known than among men in the general population. Methods:In a total of 932 women, age 66 ± 6 years at baseline, from the population-based Swedish Mammography Cohort, IgM anti-PC levels of sera were measured using Enzyme Linked Immunosorbent assay. Prospective associations with any first CVD, ischemic heart disease (IHD), myocardial infarction (MI), and ischemic stroke were assessed using Cox proportional hazard regression, generating HRs and 95% CIs. The model was adjusted for potential confounding factors. Results:Over the course of 16 years (13,033 person-years), we identified 113 cases of composite CVD, 69 cases of IHD, 44 cases of MI, and 50 cases of ischemic stroke. IgM anti-PC was statistically significantly inversely associated with risk of CVD, IHD, and MI, but not with ischemic stroke. Comparing the highest tertile with lowest, we observed multivariable-adjusted HR of 0.27 (95% CI: 0.11-0.68; P trend <0.01) for MI. Conclusions:IgM anti-PC may play an active role in inhibition of CVD development in women, especially MI. Furthermore, IgM anti-PC levels may play a role in identifying those at risk.
Background A high total phosphorus (P) intake has been proposed to promote endothelial dysfunction and atherosclerosis. A diet rich in foods containing P additives could contribute to an excessive intake, potentially reflected as increased concentration of P in urine. Objectives This study aimed to assess the intake of total dietary P, P additives, and its sources and examine their correlation with urinary P in a cross-sectional national study in Swedish adolescents. Methods We constructed a database of P additives and applied it to the foods consumed by 3099 participants in the representative school-based dietary survey Riksmaten Adolescents 2016–17. Intake of total dietary P and P additives were assessed using two 24-h recalls. Urinary P was analyzed in a subsample of 756 participants using inductively coupled plasma mass spectrometry. Spearman rank correlation (ρ) was used to assess the association between dietary P intake and urinary P excretion. Results The mean (SD) intake of total P was 1538 (±667) mg/d. Food containing P additives were consumed by 92% of adolescents and the median (IQR) intake was 49 (22–97; range: 0.01–947) mg/d, corresponding to 5% (1%–6%; range: 0%–50%) of total P. The main contributing food to P additives was cola drinks, while the main contributing food group was sausage dishes. Total P intake was weakly correlated with urinary P (ρ = 0.12; P < 0.01) but not with intake of P additives. Conclusions Nearly, all participants consumed P additives, contributing to an average of 5% of total P intake but ranging up to 50%. The intake of total P, but not P additives, was weakly reflected in the urinary P. Access to more comprehensive information on P additives in foods would improve further evaluation of potential health consequences.
Objectives This study aimed to systematically review the evidence for associations between consumption of legumes and cardiovascular disease (CVD), type 2 diabetes (T2D) and their risk factors among healthy adults. Methods We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Scopus up to 16 May 2022 for ≥4 weeks long randomized (RCT) and non-randomized controlled trials and prospective cohort studies with follow-up ≥12 months, assessing legume intake (beans/lentils/peas/soybeans, excluding peanuts and legume-products/protein/powder/flour) as the intervention or exposure. Outcomes were CVD, coronary heart disease (CHD), stroke, T2D and in intervention trials only: changes in blood lipids, glycemic markers, and blood pressure. Risk of bias (RoB) was evaluated with Cochrane’s RoB2, ROBINS-I, and US Department of Agriculture (USDA)’s RoB-NObS. Effect sizes were pooled using random-effects meta-analyses and expressed as relative risk or weighed mean differences with 95% confidence intervals, heterogeneity quantified as I2. The evidence was appraised according to World Cancer Research Fund’s criteria. Results Of the 181 full-text articles assessed for eligibility, 47 were included: 31 cohort studies (2,081,432 participants with generally low legume consumption), 14 crossover RCTs (448 participants), one parallel RCT and one non-randomized trial. Meta-analyses of cohort studies were suggestive of null associations for CVD, CHD, stroke and T2D. Meta-analyses of RCTs suggested a protective effect on total cholesterol (mean difference −0.22 mmol/L), low density lipoprotein (LDL)-cholesterol (−0.19 mmol/L), fasting glucose (−0.19 mmol/L), and HOMA-IR (−0.30). Heterogeneity was high (I2 = 52% for LDL-cholesterol, >75% for others). The overall evidence for associations between consumption of legumes and risk of CVD and T2D was considered limited – no conclusion. Conclusion Legume consumption was not found to influence risk of CVD and T2D in healthy adult populations with generally low legume consumption. However, protective effects on risk factors, seen in RCTs, lend some support for recommending legume consumption as part of diverse and healthy dietary patterns for prevention of CVD and T2D.
Objective: To systematically review the evidence for whether habitual or different levels of experimental intake of vitamin B12 from diet and supplements is sufficient to ensure adequate B12 status in groups most susceptible to vitamin B12 deficiency. Methods: We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials and Scopus up to 21 May 2021, for intervention studies, prospective cohort studies and case-control studies assessing B12 intake from diet and/or supplements in relation to B12 status (s/p-B12, holotranscobalamin, methylmalonic acid, homocysteine or breastmilk B12). Cross-sectional studies were eligible for studies conducted during pregnancy and lactation. Included populations were children (0–18 years), young adults (18–35 years), pregnant or lactating women, older adults (≥65 years) and vegans or vegetarians. Study selection, data extraction and risk of bias assessment were conducted by two assessors independently. The evidence was synthesized qualitatively and classified according to the World Cancer Research Fund. Results: The searches yielded 4855 articles of which 89 were assessed in full text and 18 included. Three studies were conducted during pregnancy and three during lactation or infancy – all observational. Eight studies were conducted among older adults; most were interventions among B12-deficient participants. Four studies were eligible for vegetarian and vegans, all interventions. The strength of evidence that habitual B12 intake or an intake in line with the current Nordic recommended intake (RI) is sufficient to ensure adequate status was considered Limited – no conclusion for all included populations. Conclusion: Evidence is insufficient to assess if or which level of B12 intake is sufficient to maintain adequate status for all included populations. Population-based cohort studies and low-to-moderate dose interventions that address this question are highly warranted.
Background: While dietary fiber intake is low in many children, the current trend to plant-based diets is associated with higher fiber intake in children raised on these diets. As older reports indicate that diets providing high fiber intake in children 0–5 years may affect growth, iron status and bowel function, we summarized the available evidence in this systematic review. Objective: To identify, critically appraise, and synthesize evidence on the effect of high fiber intake on growth, iron and bowel function in children 0–5 years, with relevance to the Nordic and Baltic countries. Methods: Following a pre-registered protocol, we searched MEDLINE, EMBASE, Cochrane Central of Controlled Trials, and Scopus for clinical trials and prospective cohort studies published until November 2021. Two reviewers independently screened retrieved literature, extracted relevant data, and performed risk of bias assessment. Outcomes were growth, iron metabolism and bowel function in children 0–5 years. We narratively described findings from studies that met inclusion criteria. Results: From 5,644 identified records, five articles met the inclusion criteria. Two RCTs had an overall moderate risk of bias, while the three observational studies had serious risk. Overall, we found no robust association between high intake of dietary fiber and growth. In the RCTs, higher intake of fiber had a positive effect on bowel movements and constipation. No studies on fiber intake and iron status were identified. The certainty of the overall evidence was inconclusive for growth and bowel function, while no assessment was made for iron status. Conclusion: We found no clear association between high intake of dietary fiber and growth or bowel function in young children living in affluent countries, albeit with only a limited number of studies. There is a lack of studies investigating health effects of high fiber intake in small children.
Objectives: To systematically review the evidence on the effect of replacing the intake of animal protein with plant protein on cardiovascular disease (CVD) and type 2 diabetes (T2D) and their intermediate risk factors. Methods: We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Scopus up to 12th May 2022 for randomized controlled trials (RCTs) or prospective cohort studies that investigated replacement of animal protein with plant protein from foods. Outcomes were CVDs, T2D, and in RCTs also the effects on blood lipids, glycemic markers, and blood pressure. Risk of bias was evaluated with the Cochrane's RoB2, ROBINS-I, and USDA's RoB-NObS tools. Random-effects meta-analyses assessed the effects of plant vs. animal proteins on blood lipids in RCTs. The evidence was appraised according to the World Cancer Research Fund's criteria. Results: After screening 15,090 titles/abstracts, full text of 124 papers was scrutinized in detail, from which 13 RCTs and seven cohort studies were included. Eight of the RCTs had either some concern or high risk of bias, while the corresponding evaluation of cohort studies resulted in moderate risk of bias for all seven. Meta-analyses of RCTs suggested a protective effect on total cholesterol (mean difference-0.11 mmol/L; 95% CI-0.22,-0.01) and low-density lipoprotein cholesterol (-0.14 mmol/L; 95% CI-0.25,-0.02) by replacing ani-mal protein with plant protein. The substitution of animal protein with plant protein (percentage of energy intake) in cohort studies was associated with lower CVD mortality (n = 4) and lower T2D incidence (n = 2). The evidence was considered limited-suggestive for both outcomes. Conclusion: Evidence that the substitution of animal protein with plant protein reduces risk of both CVD mortality and T2D incidence is limited-suggestive. Replacing animal protein with plant protein for aspects of sustainability may also be a public health strategy to lower the risk of CVD mortality and T2D.
Objectives: We aimed to systematically review studies and evaluate the strength of the evidence on nuts/seeds consumption and cardiometabolic diseases and their risk factors among adults. Methods: A protocol was pre-registered in PROSPERO (CRD42021270554). We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials and Scopus up to September 20, 2021 for prospective cohort studies and ≥12-week randomized controlled trials (RCTs). Main outcomes were cardiovascular disease (CVD), coronary heart disease (CHD), stroke and type 2 diabetes (T2D), secondary total-/low density lipoprotein (LDL)-cholesterol, blood pressure and glycaemic markers. Data extraction and risk of bias (RoB) assessments (using RoB 2.0 and RoB-NObS) were performed in duplicate. Effect sizes were pooled using random-effects meta-analyses and expressed as relative risk (RR) or weighted mean differences with 95% confidence intervals (CI); heterogeneity quantified as I2. One-stage dose-response analyses assessed the linear and non-linear associations with CVD, CHD, stroke and T2D. The strength of evidence was classified per the World Cancer Research Fund criteria. Results: After screening 23,244 references, we included 42 papers from cohort studies (28 unique cohorts, 1,890,573 participants) and 18 RCTs (2,266 participants). In the cohorts, mainly populations with low consumption, high versus low total nuts/seeds consumption was inversely associated with total CVD (RR 0.81; 95% CI 0.75, 0.86; I2 = 67%), CVD mortality (0.77; 0.72, 0.82; I2 = 59.3%), CHD (0.82; 0.76, 0.89; I2 = 64%), CHD mortality (0.75; 0.65, 0.87; I2 = 66.9%) and non-fatal CHD (0.85; 0.75, 0.96; I2 = 62.2%). According to the non-linear dose-response analyses, consumption of 30 g/day of total nuts/seeds was associated with RRs of similar magnitude. For stroke and T2D the summary RR for high versus low intake was 0.91 (95% CI 0.85, 0.97; I2 = 24.8%) and 0.95 (0.75, 1.21; I2 = 82.2%). Intake of nuts (median ~50 g/day) lowered total (−0.15 mmol/L; −0.22, −0.08; I2 = 31.2%) and LDL-cholesterol (−0.13 mmol/L; −0.21, −0.05; I2 = 68.6%), but not blood pressure. Findings on fasting glucose, HbA1c and insulin resistance were conflicting. The results were robust to sensitivity and subgroup analyses. We rated the associations between nuts/seeds and both CVD and CHD as probable. There was limited but suggestive evidence for no association with stroke. No conclusion could be made for T2D. Conclusion: There is a probable relationship between consumption of nuts/seeds and lower risk of CVD, mostly driven by CHD, possibly in part through effects on blood lipids. More research on stroke and T2D may affect the conclusions. The evidence of specific nuts should be further investigated.
Objective: To identify, critically appraise, and synthesize evidence on the effect of quality of dietary fat intake and different classes of fatty acids on the risk of Alzheimer’s disease (AD) and dementia in adults aged ≥50 years. Methods: We searched MEDLINE, EMBASE, Cochrane Central of Controlled Trials, and Scopus for clinical trials and prospective cohort studies published until May 2021. Two reviewers independently screened retrieved literature, extracted relevant data, and performed risk of bias assessment. Classes of fatty acids included were saturated fatty acids (SFAs), trans fatty acids (TFAs), monounsaturated fatty acids (MUFAs), poly-unsaturated fatty acids (PUFAs), and their subtypes and sources. Given between-study heterogeneity, we did not perform meta-analyses but narratively described findings from the studies. Results: From 4,491 identified records, five articles (based on four prospective cohort studies) met the inclusion criteria. Three studies had an overall serious risk of bias, while one study had a moderate risk. Overall, we found no robust association between intake of any fatty acids type and the development of AD and dementia. For example, for SFA and TFA, there was contradictory associations reported on AD: one study found that each unit increase in energy-adjusted intake of SFA (risk ratio [RR] 0.83, 95%CI 0.70–0.98) and TFA (RR 0.80, 95%CI 0.65–0.97) was associated with a decreased risk of AD, but not dementia. For PUFA, one study found that higher quintile intake of marine-based n-3 PUFA was associated with a decreased risk of AD. The intake of other fatty acids was not associated with the outcomes. The certainty of the overall evidence was inconclusive. Conclusion: We found no clear association between the intake of various classes of fatty acids and the risk of AD and dementia in adults. More well-designed prospective studies are required to clarify these findings.
Objective: To assess whether supplementation with long chain n-3 fatty acids during pregnancy, lactation, or infancy reduces the risk of developing asthma or atopic disease during childhood. Methods: Searches were performed in MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Scopus up to 2021-09-20, for randomized controlled trials (RCTs) that investigated the effect of supplemental long chain n-3 fatty acids during pregnancy, lactation, or infancy for the prevention of childhood asthma or allergy. Article selection, data extraction, and risk of bias assessment (Cochrane’s Risk of Bias 2.0) were independently conducted by two assessors. The evidence was synthesized qualitatively according to the criteria of the World Cancer Research Fund and meta-analyzed. Results: A total of nine RCTs met inclusion criteria; six were conducted during pregnancy, two during infancy, and one during both pregnancy and infancy. Meta-analysis showed that long chain n-3 fatty acid supplementation during pregnancy significantly reduced the risk of asthma/wheeze in the child (RR 0.62 [95% confidence interval 0.34–0.91], P = 0.005, I2 = 67.4%), but not other outcomes. Supplementation during lactation of infancy showed no effects on any outcome. The strength of evidence that long chain n-3 fatty acid supplementation during pregnancy reduces risk of asthma/wheeze in the offspring was considered limited – suggestive. No conclusion could be made for the effects of long chain n-3 fatty acid supplementation during pregnancy for other atopic diseases, or for supplementation during lactation or infancy for any outcome. Conclusion: The intake of long chain n-3 fatty acid supplements during pregnancy may reduce the risk of asthma and/or wheeze in the offspring, but the strength of evidence is low. There is inconclusive evidence for the effects of long chain n-3 fatty acid supplements during pregnancy for other outcomes, as well as for supplementation during lactation or infancy.
OBJECTIVE:The Health Star Rating (HSR) is a voluntary front-of-pack nutrition labelling system that rates products from ½ to 5 stars (five being healthiest). The Chilean Warning Label system displays warnings on foods high in sugar, saturated fat, sodium, or energy. We aimed to evaluate alignment between the systems. METHODS:New Zealand packaged products (n=13,868) were classified according to the two systems. Alignment was assessed by cross-checking the number of products meeting the criteria for warnings against star ratings. Products with no warnings but an HSR <2, or with >1 warning but an HSR of ≥3.5 were considered outliers. RESULTS:Two-thirds of products met the criteria for at least one warning. There was a significant positive relationship between the number of warnings and mean HSR: 0 warnings = HSR 3.77±.0166 (p<0.001), 1 warning = HSR 2.70±.0206 (p<0.001) and >1 warning = HSR 2.00±.0160 (p<0.001). The systems were non-aligned for 1,117 products (8%). CONCLUSION:HSR and the Chilean Warning Label systems are broadly aligned. Non-alignment is due to the Chilean system restricting warnings to foods containing added ingredients and HSR awarding points for positive components. Implications for public health: These results could be helpful in informing improvements to the HSR system.
Background: Unhealthy diet is the leading preventable risk for poor health in New Zealand. [...]