Dietary exposure to acrylamide and breast cancer risk: results from the NutriNet-Santé cohort

Double-Edged Sword Effect of Diet and Nutrition on Carcinogenic Molecular Pathways in Breast Cancer

Environmental exposure to a mixture of chemical xenobiotics acts as a double-edged sword, promoting or suppressing tumorigenesis and the development of breast cancer (BC). Before anything else, we are what we eat. In this review, we highlight both "the good" and "the bad" sides of the daily human diet and dietary patterns that could influence BC risk (BCR) and incidence. Thus, regularly eating new, diversified, colorful, clean, nutrient-rich, energy-boosting, and raw food, increases apoptosis and autophagy, antioxidation, cell cycle arrest, anti-inflammation, and the immune response against BC cells. Moreover, a healthy diet could lead to a reduction in or the inhibition of genomic instability, BC cell stemness, growth, proliferation, invasion, migration, and distant metastasis. We also emphasize that, in addition to beneficial compounds, our food is more and more contaminated by chemicals with harmful effects, which interact with each other and with endogenous proteins and lipids, resulting in synergistic or antagonistic effects. Thus, a healthy and diverse diet, combined with appropriate nutritional behaviors, can exert anti-carcinogenic effects and improve treatment efficacy, BC patient outcomes, and the overall quality of life of BC patients.

Acrylamide in alternative snacks to potato: A review

The snack food market has been changing to keep up with the growing demand for healthier products and, as a result, alternative products to traditional potato chips have been emerging to provide health-related benefits. Extrusion, frying, and baking are the main techniques used worldwide in the processing of snacks and are among the main reasons for the formation of toxic compounds induced by heat, such as acrylamide. This contaminant is formed during thermal processing in foods heated at high temperatures and rich in carbohydrates. Processed potato-based products have been pointed out as the main contributors to acrylamide dietary exposure. Many studies have been conducted on potato chips since the discovery of this contaminant in foods and research on the formation of acrylamide in snacks from other vegetables has begun to be conducted more recently. Thus, this review aims to present a detailed discussion on the occurrence of acrylamide in alternative vegetable snacks that are consumed as being healthier and to address relevant questions about the effectiveness of mitigation strategies that have been developed for these products. Through this research, it was observed that, depending on the vegetable, the levels of this contaminant can be quite variable. Alternative snacks, such as sweet potato, carrot and beetroot may also contain high levels of acrylamide and need to be monitored even more closely than potatoes snacks, as less information is available on these food products. Furthermore, various pretreatments (e.g. bleaching, immersion in solutions containing chemical substances) and processing conditions (heating methods, time, temperature) can reduce the formation of acrylamide (54-99 %) in alternative vegetable snacks.

Formation and Reduction of Toxic Compounds Derived from the Maillard Reaction During the Thermal Processing of Different Food Matrices

Advanced glycation end products (AGEs), heterocyclic aromatic amines (HAAs), acrylamide (AA), 5-hydroxymethylfurfural (5-HMF), and polycyclic aromatic hydrocarbons (PAHs) are toxic substances that are produced in certain foods during thermal processing by using common high-temperature unit operations such as frying, baking, roasting, grill cooking, extrusion, among others. Understanding the formation pathways of these potential risk factors, which can cause cancer or contribute to the development of many chronic diseases in humans, is crucial for reducing their occurrence in thermally processed foods. During thermal processing, food rich in carbohydrates, proteins, and lipids undergoes a crucial Maillard reaction, leading to the production of highly active carbonyl compounds. These compounds then react with other substances to form harmful substances, which ultimately affect negatively the health of the human body. Although these toxic compounds differ in various forms of formation, they all partake in the common Maillard pathway. This review primarily summarizes the occurrence, formation pathways, and reduction measures of common toxic compounds during the thermal processing of food, based on independent studies for each specific contaminant in its corresponding food matrix. Finally, it provides several approaches for the simultaneous reduction of multiple toxic compounds.

The antioxidant protective effect of resveratrol on long-term exposure to acrylamide-induced skeletal toxicity in female mice

Background

Acrylamide (AA) is a toxic substance formed when cooking starch-based foods at high temperatures. Studies have shown that AA can cause neurotoxicity, reproductive toxicity and so on. However, there remains limited understanding of the potential skeletal toxicity of AA.

Objective

The aim of this study was to investigate the potential skeletal toxicity of AA, as well as the potential bone protective effects of Resveratrol (RVT).

Methods

Based on the daily intake of adult women, adult female mice was treated with AA at 0, 0.01, 0.1, 1 mg/kg/d or AA/RVT (1 mg/kg/d AA +10 mg/kg/d RVT) for 8 weeks, and skeletal toxicity were evaluated by RT-qPCR and histopathological techniques.

Results

The results found that exposure to AA (0.1 or 1 mg/kg/d) after 8 weeks, osteogenesis exhibited pathological damage characteristics such as inhibition of growth plate function, and reduction of fibrous tissue, and cartilage exhibited pathological damage characteristics such as irregular cell morphology and arrangement, and damage to the tidal line. The results of cellular functional gene testing showed a decrease in the expression of functional genes in osteoblasts and chondrocytes. Meanwhile, after further co-treatment with AA (1 mg/kg/d) and resveratrol (RVT) (10 mg/kg/d), we found that RVT restored AA-induced damage to osteogenesis and cartilage, and reduced the high apoptosis and oxidative stress levels in osteogenesis/cartilage after AA exposure.

Conclusion

In summary, this study confirmed the skeletal toxicity of AA on female adult mice, and further clarified the antioxidant protective effect of RVT on this toxicity.

Epicatechin-Promoted Formation of Acrylamide from 3-Aminopropionamide Via Postoxidative Reaction of B-Ring

The role of thermally generated 3-aminopropionamide as an intermediate in acrylamide formation in the Maillard reaction has been well established. Herein, the effect of epicatechin on the conversion of 3-aminopropionamide into acrylamide under oxidative conditions was investigated at 160-220 °C. Epicatechin promoted acrylamide generation and 3-aminopropionamide degradation. The stable isotope-labeling technique combined with UHPLC-Orbitrap-MS/MS analysis showed adduct formation between 3-aminopropionamide and the oxidized B ring of epicatechin to form a Schiff base. This initially formed Schiff base could directly degrade to acrylamide, undergo reduction or dehydration to other intermediates, and subsequently generate acrylamide. Based on accurate mass analysis, five intermediates with intact or dehydrated C rings were tentatively identified. Furthermore, reaction pathways were proposed that were supported by the changes in the levels of adducts formed during heating. To the authors' knowledge, this study is the first to reveal pathways through which flavanols promoted the formation of acrylamide in Maillard reactions.

Lactobacillus reuteri JCM 1112 ameliorates chronic acrylamide-induced glucose metabolism disorder via the bile acid-TGR5-GLP-1 axis and modulates intestinal oxidative stress in mice

Acrylamide (AA) is a toxic food contaminant that has been reported to cause glucose metabolism disorders (GMD) at high doses. However, it is unclear whether chronic low-dose AA can induce GMD and whether probiotics can alleviate AA-induced GMD. Here, C57BL/6N mice were orally administered with 5 mg per kg bw AA for 10 weeks, followed by another 3 weeks of glucagon-like peptide-1 (GLP-1) analogue (dulaglutide) treatment. Chronic low-dose AA exposure increased the blood glucose level and decreased serum insulin and GLP-1 levels, whereas dulaglutide treatment decreased the blood glucose level and increased the serum insulin level in AA-exposed mice. Then, mice were administered with AA or AA + INT-777 (Takeda G-protein-coupled receptor 5 (TGR5) agonist) for 10 weeks. INT-777 treatment reversed AA-induced downregulation of ileal TGR5 and proglucagon (PG) gene expression and decreased the serum GLP-1 level. These findings indicated that chronic low-dose AA induced GMD via inhibiting the TGR5-GLP-1 axis. Finally, mice were administered with AA for 10 weeks, followed by another 3 weeks of Lactobacillus reuteri JCM 1112 supplementation. L. reuteri supplementation significantly increased serum glucose, insulin and GLP-1 levels, upregulated ileal TGR5 and PG gene expression, and effectively restored the imbalance of bile acid (BA) metabolism in AA-exposed mice, demonstrating that L. reuteri ameliorates chronic AA-induced GMD via the BA-TGR5-GLP-1 axis. In addition, L. reuteri significantly enhanced ileal superoxide dismutase and catalase activities and total antioxidant capacity, thereby preventing chronic AA-induced oxidative stress. Our research provides new insights into the GMD toxicity of chronic low-dose AA and confirms the role of probiotics in alleviating AA-induced GMD.

Estimation of intake and quantification of hemoglobin adducts of acrylamide in adolescents in Sweden

Blood samples (n = 600) from participants in the Swedish dietary survey Riksmaten Adolescents 2016-17 were analyzed with respect to hemoglobin (Hb) adducts from acrylamide (AA) and its metabolite glycidamide (GA) as biomarkers of internal dose/exposure. The results are presented from statistical analyses of food consumption data (2-day dietary recall and questionnaires) and measured Hb adduct levels. The estimated exposure as well as consumption data were examined in relation to non-dietary factors such as sex, age (group medians of 12, 15, and 18 years), place of residence (urban/rural), smoking status, and parental education level. The median AA adduct level was estimated to be 34 pmol/g Hb (range 14-225). No significant difference was found for place of residence, parental education, sex, or age. A significant difference was found between the median adduct levels of daily smokers (n = 8) and never smokers (n = 323) in the older age groups, but not between occasional smokers (n = 47) and never smokers. The median differences between daily smokers and never smokers were 76, 40, and 128 pmol/g Hb for AA, GA, and AA + GA, respectively. The median AA intake for the whole group of adolescents, as estimated from dietary recall data combined with reported concentrations in food, was 0.40 μg/kg bw/day. The corresponding median intake estimated from measured Hb adduct levels of AA was 0.20 μg/kg bw/day. A significant, although low, positive Spearman correlation was found between the two intake estimates (p-value = 8 × 10-3; ρ = 0.11). From the estimated intake of AA from food frequency questionnaires, significance was found for the 15-year-old children with higher AA adduct levels observed at higher consumption frequencies of fried potatoes/French fries. AA is considered a genotoxic carcinogen. For the estimated intake of AA for any age group and method (dietary recall or AA adduct), both a calculated margin of exposure as well as lifetime quantitative cancer risk estimates indicate health concern. A future study on food consumption designed with respect to AA exposure would provide a better understanding of the correlation between consumption and exposure and should give a more reliable estimate of the contribution of dietary AA to the overall cancer risk.

The burden of disease due to dietary exposure to acrylamide in Italy: A risk assessment-based approach

The aim of this study was to assess Italian consumers' risk of cancer and burden of disease due to dietary exposure to acrylamide. Our model considered six age groups such as infants, toddlers, other children, adolescents, adults, and the elderly, and the consumption of 31 food items. Using a risk-assessment-based approach, we first characterized the risk of neoplastic effects using the margin of exposure method. Then the risk of kidney, endometrial, breast, ovarian cancer, and total cancer was estimated using adjusted cancer slope factors while the burden of disease was quantified using Disability-adjusted Life Years (DALYs). The highest risk for females was related to breast cancer while the lowest was for kidney cancer. We found a comparable risk of total cancer among Italian males and females, estimated at around 1.59 to 3.57 cases per 100,000 individuals annually with the burden ranging between 12.3 - 25.4 and 11.4 - 24.1 DALYs respectively. Our findings provide insights on the multifaceted impact of acrylamide on public health by offering detailed insights into age-specific exposure levels, diverse cancer risks, and the dietary burden of disease related to acrylamide. Targeted interventions and policies can be developed towards mitigating the health risks associated with acrylamide exposure.

Comparison of bladder carcinogenesis biomarkers in the urine of traditional cigarette users and e-cigarette users

Background

During the use of electronic cigarettes (e-cigarettes), users are still exposed to carcinogens similar to those found in tobacco products. Since these carcinogens are metabolized and excreted in urine, they may have carcinogenic effects on the bladder urinary tract epithelium. This meta-analysis aimed to compare bladder cancer carcinogens in the urine of tobacco users and e-cigarette users using a large number of samples.

Methods

A systematic meta-analysis was performed using data obtained from several scientific databases (up to November 2023). This cumulative analysis was performed following the Preferred Reporting Items for Systematic Evaluation and Meta-Analysis (PRISMA) and Assessing the Methodological Quality of Systematic Evaluations (AMSTAR) guidelines, according to a protocol registered with PROSPERO. This study was registered on PROSPERO and obtained the unique number: CRD42023455600.

Results

The analysis included 10 high-quality studies that considered polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs) and tobacco-specific nitrosamines (TSNAs). Statistical indicators show that there is a difference between the tobacco user group and the e-cigarette user group in terms of 1-Hydroxynaphthalene (1-NAP) [weighted mean difference (WMD)10.14, 95% confidence interval (CI) (8.41 to 11.88), p < 0.05], 1-Hydroxyphenanthrene (1-PHE) [WMD 0.08, 95% CI (-0.14 to 0.31), p > 0.05], 1-Hydroxypyrene (1-PYR) [WMD 0.16, 95% CI (0.12 to 0.20), p < 0.05], 2-Hydroxyfluorene (2-FLU) [WMD 0.69, 95% CI (0.58 to 0.80), p < 0.05], 2-Hydroxynaphthalene (2-NAP) [WMD 7.48, 95% CI (4.15 to 10.80), p < 0.05], 3-Hydroxyfluorene (3-FLU) [WMD 0.57, 95% CI (0.48 to 0.66), p < 0.05], 2-Carbamoylethylmercapturic acid (AAMA) [WMD 66.47, 95% CI (27.49 to 105.46), p < 0.05], 4-Hydroxy-2-buten-1-yl-mercapturic acid (MHBMA) [WMD 287.79, 95% CI (-54.47 to 630.04), p > 0.05], 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNAL) [WMD 189.37, 95% CI (78.45 to 300.29), p < 0.05], or N0-nitrosonornicotine (NNN) [WMD 11.66, 95% CI (7.32 to 16.00), p < 0.05].

Conclusion

Urinary bladder cancer markers were significantly higher in traditional tobacco users than in e-cigarette users.Systematic review registration: PROSPERO (CRD42023455600: https://www.crd.york.ac.uk/PROSPERO/).

Association between dietary intake of acrylamide and increased risk of mortality in women: Evidence from the E3N prospective cohort

Acrylamide is an organic compound classified as probably carcinogenic to humans because of sufficient evidence in animals but not in humans. Other health risks associated with acrylamide intake are still not fully elucidated. We aimed to study the relationship between acrylamide dietary intake and mortality in the E3N (Etude Epidémiologique auprès de femmes de l'Education Nationale) French cohort. We studied 72,585 women of the E3N prospective cohort, which completed a food frequency questionnaire in 1993. The E3N food consumption database and the food contamination database obtained from the second French total diet study were used to estimate participants' average daily acrylamide dietary intake. We estimated the associations between acrylamide dietary intake and all-cause or cause-specific mortality using Cox proportional hazard models. During follow-up (1993-2014), we identified 6441 deaths. The mean acrylamide dietary intake was 32.6 μg/day, with coffee consumption as principal contributor (48.6 %). In the fully adjusted model, we found a non-linear association between acrylamide dietary intake and all-cause mortality and a linear positive association with cardiovascular disease (HR per one STD increment [95%CI]: 1.11 [1.02; 1.21]), all-cancer (HR [95%CI]: 1.05 [1.01; 1.10]) and lung cancer (HR [95%CI]: 1.22 [1.09; 1.38]) mortality, while we observed no association with breast (HR [95%CI]: 0.94 [0.86; 1.03]) and colorectal (HR [95%CI]: 1.12 [0.97; 1.29]) cancer mortality. We highlighted an interaction between acrylamide dietary intake and smoking status in the models for all-cause and all-cancer mortality: when stratifying on smoking status, statistically significant positive associations were observed only in current smokers. This study on a large prospective cohort following more than 70,000 women for over 20 years suggests that higher acrylamide dietary intakes are associated with an increased risk of mortality. Therefore, it is essential to keep reducing acrylamide contamination and prevent dietary intake of acrylamide, especially among smokers.

Causal relationship between dietary factors and breast cancer risk: A Mendelian randomization study

Background

Previous studies have discovered an association between dietary factors and breast cancer. However, few studies have used Mendelian randomization (MR) to assess the potential causal relationship between dietary factors and breast cancer.

Methods

The exposure datasets for fresh fruit intake, dried fruit intake, salad/raw vegetable intake, cooked vegetable intake, oily fish intake, non-oily fish intake, cheese intake, and bread intake were obtained from the UK Biobank. The outcome dataset was extracted from the Breast Cancer Association Consortium (BCAC). We used the inverse variance weighted (IVW) method as the primary approach for the two-sample MR analysis. To ensure the accuracy of the results, we conducted heterogeneity and horizontal pleiotropy analyses. Additionally, multivariable MR analysis was conducted to ensure the stability of the results.

Results

Dried fruit intake was found to be a protective factor for overall breast cancer (outliers excluded: OR: 0.549; 95 % CI: 0.429-0.702; p = 1.75 × 10-6). Subtype analyses showed that dried fruit intake was inversely associated with both estrogen receptor-positive (ER+) breast cancer (outliers excluded: OR: 0.669; 95 % CI: 0.512-0.875; p = 0.003) and ER-negative (ER-) breast cancer (OR: 0.559; 95 % CI: 0.379-0.827; p = 0.004), while fresh fruit intake was inversely associated with ER- breast cancer (excluded outliers: OR: 0.510; 95 % CI: 0.308-0.846; p = 0.009). No significant causal relationship was found between other dietary intakes and breast cancer. After adjusting for the effects of possible confounders, the causal relationships found by the two-sample MR analysis remained.

Conclusion

Our study provides evidence that dried fruit intake may reduce the risk of both ER+ and ER- breast cancer, and fresh fruit intake may reduce the risk of ER- breast cancer. Other factors included in this study were not linked to breast cancer.

Ultra-processed food consumption and exposure to acrylamide in a nationally representative sample of the US population aged 6 years and older

Ultra-processed food (UPF) consumption has been associated with cardiovascular disease and cancer. Acrylamide is a probable human carcinogen commonly found in foods that are processed at high temperatures. The aim of this study was to examine the association between dietary energy contribution of UPF and acrylamide exposure, in the US. Among the 4418 participants from cross-sectional 2013-2016 National Health and Nutrition Examination Survey, aged 6+ years, with hemoglobin biomarkers of acrylamide exposure, 3959 that completed the first 24-h dietary recall and had information on all covariates were included in the study. UPF were identified based on the Nova classification system, a four-group food classification based on the extent and purpose of industrial food processing. Linear regression was used to compare average acrylamide and glycidamide hemoglobin (HbAA+HbGA) concentrations across quintiles of daily energy contribution of UPF. Adjusted geometric means of acrylamide and glycidamide hemoglobin concentrations increased monotonically from the lowest to the highest quintile of UPF consumption in the overall population. Compared to the lowest quintile, the highest quintile had 9.1% higher levels of HbAA+HbGA (94.1 vs. 86.3 pmol/g Hb). These positive associations were statistically significant among males and in the young adult population and were largely driven by UPF which are known potential sources of acrylamide. The main effects remained unchanged when excluding current smokers. As both acrylamides and UPF have been previously associated with cardiovascular disease and cancer, our results suggest that acrylamides in UPF may partially explain previously observed links between UPF consumption and these health outcomes.

Dietary Heat-Treatment Contaminants Exposure and Cancer: A Case Study from Turkey

In this study, the 10-year dietary habits of patients diagnosed with cancer (n = 1155) were retrospectively analyzed, and the relationships between dietary (red meat, white meat, fish meat, French fries, bread, instant coffee, ready-to-drink coffee, Turkish coffee, and black tea) heterocyclic amines, polycyclic aromatic hydrocarbons, acrylamide, and N-nitrosamine-based risk scores and cancer types were statistically evaluated. The foods with the highest and lowest mean dietary heat-treatment contaminant risk scores were red meat and ready-to-drink coffee, respectively. There were statistically significant differences in the dietary heat-treatment contamination risk scores based on the cancer patients' demographic characteristics (sex, age, smoking, and body mass index) (p < 0.05). According to the cancer types, the systems with the highest and lowest dietary heat-treatment contaminant risk scores were determined as other (brain, thyroid, lymphatic malignancies, skin, oro- and hypopharynx, and hematology) and the reproductive (breast, uterus, and ovary) system, respectively. The relationship between instant coffee consumption and respiratory system cancer types, the frequency of consumption of French fries and urinary system cancer types and the consumption of meat products and gastrointestinal system cancer types were determined. It is thought that this study contains important findings regarding the relationship between dietary habits and cancer and will be a good source for other studies to be conducted in this context.