Red and processed meat consumption and gastric cancer risk: a systematic review and meta-analysis

Unveiling the Younger Face of Gastric Cancer: A Comprehensive Review of Epidemiology, Risk Factors, and Prevention Strategies

Gastric cancer poses a significant global health challenge, with high incidence and mortality rates each year. Despite advancements in screening and treatment, late detection remains a critical issue. Efforts to address this include raising public awareness and implementing targeted screening programs for high-risk populations. The increasing incidence of gastric cancer among younger individuals underscores the need for lifestyle adjustments and targeted interventions to mitigate risks and improve outcomes. Understanding the various factors contributing to gastric cancer risk is essential for effective prevention strategies, including Helicobacter pylori eradication, lifestyle modifications, and regular screening for high-risk groups. A comprehensive approach addressing both individual behaviors and broader societal factors is crucial in the fight against gastric cancer. This review provides an in-depth examination of gastric cancer epidemiology, risk factors, preventive measures, and screening initiatives, with a particular focus on the rising incidence among younger demographics. Emphasizing the importance of early detection and intervention, the review highlights the need for proactive screening to improve patient outcomes and reduce mortality rates. By addressing these aspects comprehensively, this paper aims to enhance the understanding of gastric cancer dynamics, particularly its incidence among younger individuals, and to inform future strategies for prevention and control.

Review of dietary patterns and gastric cancer risk: epidemiology and biological evidence

Due to rapid research expansion on dietary factors and development of cancer prevention guidelines, the field of dietary pattern and its relationship to cancer risk has gained more focus. Numerous epidemiology studies have reported associations between Gastric Cancer (GC) and both data-driven posteriori dietary pattern and priori dietary pattern defined by predetermined dietary indexes. As dietary patterns have evolved, a series of patterns based on biological markers has advanced, offering deeper insights into the relationship between diet and the risk of cancer. Although researches on dietary patterns and cancer risk are booming, there is limited body of literature focusing specifically on GC. In this study, we compare the similarities and differences among the specific components of dietary patterns and indices, summarize current state of knowledge regarding dietary patterns related to GC and illustrate their potential mechanisms for GC prevention. In conclusion, we offer suggestions for future research based on the emerging themes within this rapidly evolving field.

LDHA and LDHB overexpression promoted the Warburg effect in malignantly transformed GES-1 cells induced by N-nitroso compounds

N-nitroso compounds (NOCs) exposure is a major risk factor for the development of gastric cancer. However, the carcinogenic mechanisms by which NOCs induce gastric and other cancers, especially the NOCs-induced Warburg effect, have not been comprehensively studied. Lactate dehydrogenase (LDH), which has two subunits (LDHA and LDHB), plays an important role in the Warburg effect of tumor cells. Therefore, we hypothesized that LDHA and LDHB could promote Warburg effect in malignant transformed GES-1 cells induced by Nmethyl-N'-nitro-N-nitrosoguanidine (MNNG). GES-1 cells were exposed to 1 μmol/L MNNG and cultured for 40 passages. During the culturing process, cell proliferation, migration, and soft agar colony formation significantly increased after 30 passages. Following MNNG exposure, lactate, LDH, glucose uptake, and the expression levels of key enzymes in glycolysis were significantly increased. Knocking down LDHA or LDHB alone reduced lactate secretion, inhibited cell viability, and impaired migratory capacities. Knocking down LDHA and LDHB together fully suppressed lactate secretion and effectively suppressed the malignant phenotype of cells transformed by long-term MNNG exposure. Finally, we demonstrated that overexpression of LDHA and LDHB promotes the malignant transformation of GES-1 cells by enhancing the Warburg effect during long-term exposure to NOCs.

Sex-specific effects of fruit, vegetable, and red meat intake on the risk of gastric and esophageal cancer in a large cohort

BACKGROUND

Dietary effects on gastric and esophageal cancer by sex and smoking has rarely been investigated.

METHODS

Individuals who had undergone national gastric cancer screening during 2008 and had no any cancer at baseline were enrolled and followed up to 2017. The gastric and esophageal cancer risk was measured using adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs).

RESULTS

Among 3.645 million (44.1% men), 45,741 gastric cancers (67.7% men) and 3,550 esophageal cancers (89.5% men) developed during 9 years follow-up. In adjusted analysis, a frequent intake of fruit (≥ 7 servings per week) reduced the gastric cancer risk (aHR=0.91; 95% CI, 0.83-0.99) comparing to nearly no intake in women but slightly increased male gastric cancer risk (aHR=1.06; 95% CI, 1.00-1.13). A frequent intake of dietary fruit reduced the esophageal cancer risk only in men (aHR=0.75; 95% CI, 0.62-0.92). Frequent intake of red meat (3-4/week) slightly increased the gastric cancer risk only in men (aHR=1.04; 95% CI, 1.01-1.09). The favorable effect of fruit on the gastric and esophageal cancer risk was observed only in never smoker.

CONCLUSIONS

The effect of fruit and red meat intake on the gastric and esophageal cancer risk differed according to sex and smoking status.

Comprehensive Review of Red Meat Consumption and the Risk of Cancer

Red and processed meat consumption rates are increasing in the United States. In this review, we present the current evidence that links red meat consumption and cancer development. A literature search was conducted in the PubMed and Google Scholar databases to review red meat consumption and its association with breast cancer and gastrointestinal cancer. Due to the presence of heme iron, which triggers oxidative reactions that eventually result in tumor formation, red meat consumption is strongly associated with the development of breast cancer. Ingestion of red meat increases Helicobacter pylori infections, resulting in enhanced expression of the CagA gene and the secretion of pro-inflammatory cytokines. This is the leading cause of gastric cancer. There is a strong correlation between heterocyclic amines and polycyclic aromatic hydrocarbons in red meat and the development of pancreatic cancer. However, additional research is necessary to confirm this finding. Adult colorectal cancer is caused by the formation of heterocyclic amines and DNA adducts due to the intake of red and processed meats cooked at higher temperatures. The consumption of poultry is associated with a reduced risk of breast and gastrointestinal cancers, but the results are inconsistent. The evidence is strong for the association between red meat and breast cancer and most gastric cancers. The presence of aromatic hydrocarbons, heterocyclic amines, and heme iron in red meat has been found to be behind tumorigenesis. Poultry has been shown to have a low association with cancer, but additional research is needed.

Meat and dairy products intake is associated with gastric cancer: Case-control study findings

Countries experiencing a significant shift toward Western lifestyle are facing an increased risk of gastric cancer (GC). While many studies have explored the link between diet and GC, the role of meat and dairy consumption remains uncertain. To delve deeper into this association, we conducted a case-control study in Jordan involving 173 GC cases and 314 controls, matched by age and marital status. Using a validated food frequency questionnaire, we assessed the intake of different dairy and meat products. The adjusted odds ratios and corresponding 95% confidence intervals indicated a strong correlation between high intake of red meat, milk, and buttermilk and GC. Our multinomial logistic regression analysis revealed that daily consumption of red meat (≥1 serving/day; OR, 3.34 [95% CI 1.85-6.03, p value of trend <.001], ≥1 serving/day) and weekly intake of milk (2-3 servings/week; OR, 2.04 [95% CI 1.14-3.64, p value of trend = .041]) and buttermilk (2-3 servings/week; OR, 2.07 [95% CI 1.12-3.83, p value of trend = .018], per 2-3 servings/week) were significantly associated with an increased risk of GC. Furthermore, consuming cooked eggs daily (OR = 2.44, 95% CI 1.24-4.79, p trend <.001) or weekly (OR, 3.34, 95% CI 1.58-7.10, p value of trend <.001) was also associated with an increased risk of GC. These findings highlight the potential health risks associated with excessive meat and some dairy products consumption and suggest that a balanced intake of these products, along with eggs, may help prevent GC.

Gastric microbiota: an emerging player in gastric cancer

Gastric cancer (GC) is a common cancer worldwide with a high mortality rate. Many microbial factors influence GC, of which the most widely accepted one is Helicobacter pylori (H. pylori) infection. H. pylori causes inflammation, immune reactions and activation of multiple signaling pathways, leading to acid deficiency, epithelial atrophy, dysplasia and ultimately GC. It has been proved that complex microbial populations exist in the human stomach. H. pylori can affect the abundance and diversity of other bacteria. The interactions among gastric microbiota are collectively implicated in the onset of GC. Certain intervention strategies may regulate gastric homeostasis and mitigate gastric disorders. Probiotics, dietary fiber, and microbiota transplantation can potentially restore healthy microbiota. In this review, we elucidate the specific role of the gastric microbiota in GC and hope these data can facilitate the development of effective prevention and therapeutic approaches for GC.

Global burden of gastric cancer: epidemiological trends, risk factors, screening and prevention

Gastric cancer remains a major cause of cancer-related mortality worldwide. The temporal trends for this malignancy, however, are dynamic, and reports from the past decade indicate important declines in some regions and demographic groups, as well as a few notable exceptions in which gastric cancer rates are either stable or increasing. Two main anatomical subtypes of gastric cancer exist, non-cardia and cardia, with different temporal trends and risk factors (such as obesity and reflux for cardia gastric cancer and Helicobacter pylori infection for non-cardia gastric cancer). Shifts in the distribution of anatomical locations have been detected in several high-incidence regions. H. pylori is an important aetiological factor for gastric cancer; importantly, the anticipated long-term findings from studies examining the effect of H. pylori eradication on the risk of (re)developing gastric cancer have emerged in the past few years. In this Review, we highlight the latest trends in incidence and mortality using an evidence-based approach. We make the best possible inferences, including clinical and public health inference, on the basis of the quality of the evidence available, and highlight burning questions as well as gaps in knowledge and public health practice that need to be addressed to reduce gastric cancer burden worldwide.

Dietary patterns and risk for gastric cancer: A case-control study in residents of the Huaihe River Basin, China

Aim

Evidence linking dietary patterns and the risk of gastric cancer was limited, especially in Chinese populations. This study aimed to explore the association between dietary patterns and the risk of gastric cancer in residents of the Huaihe River Basin, China.

Methods

The association between dietary patterns and the risk of gastric cancer was investigated through a case-control study. Dietary patterns were identified with factor analysis based on responses to a food frequency questionnaire (FFQ). Gastric cancer was diagnosed according to the International Classification of Diseases, 10th Revision (ICD 10). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated across the tertiles of dietary pattern scores using unconditional logistic regression models.

Results

A total of 2,468 participants were included in this study. Six main dietary patterns were extracted, and those patterns explained 57.09% of the total variation in food intake. After adjusting for demographic characteristics, lifestyle factors, individual disease history, family history of cancer and Helicobacter. Pylori (H. pylori) infection, comparing the highest with the lowest tertiles of dietary pattern scores, the multivariable ORs (95% CIs) were 0.786 (0.488, 1.265; P _trend < 0.001) for the flavors, garlic and protein pattern, 2.133 (1.299, 3.502; P _trend < 0.001) for the fast food pattern, 1.050 (0.682, 1.617; P _trend < 0.001) for the vegetable and fruit pattern, 0.919 (0.659, 1.282; P _trend < 0.001) for the pickled food, processed meat products and soy products pattern, 1.149 (0.804, 1.642; P _trend < 0.001) for the non-staple food pattern and 0.690 (0.481, 0.989; P _trend < 0.001) for the coffee and dairy pattern.

Conclusions

The specific dietary patterns were associated with the risk of gastric cancer. This study has implications for the prevention of gastric cancer.

Meat Intake, Cooking Methods, Doneness Preferences and Risk of Gastric Adenocarcinoma in the MCC-Spain Study

BACKGROUND

The association of meat intake with gastric adenocarcinoma is controversial. We examined the relation between white, red, and processed meat intake and gastric adenocarcinoma, considering doneness preference and cooking methods, by histological subtype and anatomical subsite.

METHODS

MCC-Spain is a multicase-control study that included 286 incident gastric adenocarcinoma cases and 2993 controls who answered a food-frequency questionnaire. The association of gastric adenocarcinoma with meat intake, doneness preference and cooking methods was assessed using binary multivariate logistic regression mixed models and a possible interaction with sex was considered. Multinomial logistic regression models were used to estimate risk by tumor subsite (cardia vs. non-cardia) and subtype (intestinal vs. diffuse). Sensitivity analyses were conducted comparing models with and without data on Helicobacter pylori infection.

RESULTS

The intake of red and processed meat increased gastric adenocarcinoma risk (OR for one serving/week increase (95% CI) = 1.11 (1.02;1.20) and 1.04 (1.00;1.08), respectively), specifically among men and for non-cardia and intestinal gastric adenocarcinoma. Those who consume well done white or red meat showed higher risk of non-cardia (white: RRR = 1.57 (1.14;2.16); red: RRR = 1.42 (1.00;2.02)) and intestinal tumors (white: RRR = 1.69 (1.10;2.59); red: RRR = 1.61 (1.02;2.53)) than those with a preference for rare/medium doneness. Stewing and griddling/barbequing red and white meat, and oven baking white meat, seemed to be the cooking methods with the greatest effect over gastric adenocarcinoma. The reported associations remained similar after considering Helicobacter pylori seropositivity.

CONCLUSIONS

Reducing red and processed meat intake could decrease gastric adenocarcinoma risk, especially for intestinal and non-cardia tumors. Meat cooking practices could modify the risk of some gastric cancer subtypes.

Sialic acid and food allergies: The link between nutrition and immunology

Food allergies (FA), a major public health problem recognized by the World Health Organization, affect an estimated 3%-10% of adults and 8% of children worldwide. However, effective treatments for FA are still lacking. Recent advances in glycoimmunology have demonstrated the great potential of sialic acids (SAs) in the treatment of FA. SAs are a group of nine-carbon α-ketoacids usually linked to glycoproteins and glycolipids as terminal glycans. They play an essential role in modulating immune responses and may be an effective target for FA intervention. As exogenous food components, sialylated polysaccharides have anti-FA effects. In contrast, as endogenous components, SAs on immunoglobulin E and immune cell surfaces contribute to the pathogenesis of FA. Given the lack of comprehensive information on the effects of SAs on FA, we reviewed the roles of endogenous and exogenous SAs in the pathogenesis and treatment of FA. In addition, we considered the structure-function relationship of SAs to provide a theoretical basis for the development of SA-based FA treatments.

On the Role of Dietary Nitrate in the Maintenance of Systemic and Oral Health

The assessment of the significance of nitrates ingested with food has undergone a fundamental change in recent years after many controversial discussions. While for a long time, a diet as low in nitrates as possible was advocated on the basis of epidemiological data suggesting a cancer-promoting effect of nitrate-rich diets, more recent findings show that dietary nitrate, after its conversion to nitrite by nitrate-reducing bacteria of the oral microbiota, is an indispensable alternative source for the formation of nitric oxide (NO), which comprises a key element in the physiology of a variety of central body functions such as blood pressure control, defense against invading bacteria and maintenance of a eubiotic microbiota in the gut and oral cavity. This compact narrative review aims to present the evidence supported by clinical and in vitro studies on the ambivalent nature of dietary nitrates for general and oral health and to explain how the targeted adjuvant use of nitrate-rich diets could open new opportunities for a more cause-related control of caries and periodontal disease.

Diet and Risk of Gastric Cancer: An Umbrella Review

Several dietary exposures have been associated with gastric cancer (GC), but the associations are often heterogenous and may be afflicted by inherent biases. In the context of an Umbrella Review (UR), we provide an overview and a critical evaluation of the strength and quality, and evidence classification of the associations of diet-related exposures in relation to the risk of GC. We searched PubMed and Scopus for eligible meta-analyses of observational studies published in English from inception to 12 December 2021, and for any identified association, we applied robust epidemiological validity evaluation criteria and individual study quality assessment using AMSTAR. We screened 3846 titles/abstracts and assessed 501 full articles for eligibility, of which 49 were included in the analysis, investigating 147 unique exposures in relation to GC, cardia (GCC) or non-cardia (GNCC) cancer. Supported by suggestive evidence, positive associations were found comparing the highest vs. lowest categories for: heavy (>42 g/day) alcohol consumption (Relative Risk (RR) = 1.42, 95% Confidence Interval (CI): 1.20−1.67), salted fish consumption (RR = 1.56, 95% CI:1.30−1.87) and waist circumference (RR = 1.48, 95% CI:1.24−1.78) and an inverse association for the healthy lifestyle index (RR = 0.60, 95% CI:0.48−0.74) in relation to GC. Additionally, a positive association was found comparing obese individuals (Body Mass Index (BMI) ≥ 30) to normal-weight individuals (BMI: 18.5−25) (RR = 1.82, 95% CI:1.32−2.49) in relation to GCC. Most of the meta-analyses were of medium-to-high quality (median items: 7.0, interquartile range: 6−9). Maintaining a normal body weight and adopting healthy dietary choices, in particular, limiting the consumption of salt-preserved foods and alcohol, can reduce the risk of gastric cancer.

The Impact of Herbal Additives for Poultry Feed on the Fatty Acid Profile of Meat

Researchers often found that herbal additives to chicken feed can favorably alter the fatty acid profile of the meat. The most desirable effects of diet modification comprise an increased content of polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFA) and a reduced content of saturated fatty acids (SFA) in the breast and thigh muscles. A modified fatty acid profile contributes to improvement in the quality of poultry meat, which is reflected in its increased consumption. However, it may be problematic that PUFAs are oxidized easier than other lipids, which can have a negative impact on the sensory traits of meat. By contrast, herbs and herbal products contain antioxidants that can prevent the oxidation of unsaturated fatty acids and cholesterol present in animal-origin products and increase the antioxidant potential of the consumer’s body. This paper aims to review the influence of herbal additives for broiler chicken diets on the fatty acid profile of poultry meat. Special attention was paid to changes in the content of SFAs, MUFAs, and PUFAs, but also alterations in the omega-6:omega-3 ratio. The presented reference literature supports the statement that herbs and bioactive components of herbs added to chicken diets can improve the quality of broiler chicken meat by altering the content of fatty acids.

Consumption of Thermally Processed Meat Containing Carcinogenic Compounds (Polycyclic Aromatic Hydrocarbons and Heterocyclic Aromatic Amines) versus a Risk of Some Cancers in Humans and the Possibility of Reducing Their Formation by Natural Food Additives-A Literature Review

(1) Background: Thermal treatment of high-protein food may lead to the formation of mutagenic and carcinogenic compounds, e.g., polycyclic aromatic hydrocarbons and heterocyclic aromatic amines. Frequent consumption of processed meat was classified by the International Agency for Research on Cancer as directly carcinogenic for humans. (2) Methods: A literature review was carried out based on a search of online databases for articles on consuming thermally processed meat containing carcinogenic compounds versus a risk of cancers in humans published between 2001 and 2021. (3) Results: A review of the current literature on the participation of PAHs and HAA in the formation of certain neoplasms indicates a positive relationship between diet and the incidences of many cancers, especially colon cancer. A simple way to obtain dishes with reduced contents of harmful compounds is the use of spices and vegetables as meat additives. These seasonings are usually rich in antioxidants that influence the mechanism of HAA and PAH synthesis in food. (4) Conclusions: As there is a growing risk of a cancer tendency because of exposing humans to PAHs and HAAs, it is extremely vital to find a simple way to limit carcinogenic compound synthesis in a processed proteinaceous food. Disseminating the knowledge about the conditions for preparing dishes with a reduced content of carcinogenic compounds could become a vital element of cancer prevention programs.

Spicy and Aromatic Plants for Meat and Meat Analogues Applications

Aromatic and spicy plants are an important factor that contributes not only to improving the taste of meat, meat products, and meat analogues, but also to increasing the nutritional value of the products to which they are added. The aim of this paper is to present the latest information on the bioactive antioxidant and antimicrobial properties of the most commonly used herbs and spices (parsley, dill, basil, oregano, sage, coriander, rosemary, marjoram, tarragon, bay, thyme, and mint) used in the meat and meat analogues industry, or proposed to be used for meat analogues.

Meat consumption and gastric cancer risk: the Japan Public Health Center-based Prospective Study

BACKGROUND

The association of meat consumption with gastric cancer is inconclusive.

OBJECTIVES

We examined the association of meat consumption with gastric cancer risk among Japanese men and women.

METHODS

This cohort study included 42,328 male and 48,176 female participants of the Japan Public Health Center-based Prospective Study, who were aged 45 to 74 y at recruitment. Dietary intake data were collected from 1 January 1995 to 31 December 1999 using a validated food-frequency questionnaire. HRs and 95% CIs for gastric cancer were estimated using Cox proportional hazards regression models.

RESULTS

During a mean follow-up of 15 y, 1868 male and 833 female incident gastric cancer cases were identified. Intake of total and subtypes of meat was not associated with total gastric cancer. However, higher chicken consumption was associated with reduced distal gastric cancer risk in women (HR for quintile 5 vs. quintile 1: 0.75; 95% CI: 0.56, 0.99; P-trend = 0.027), with a similar but nonsignificant risk reduction among women with Helicobacter pylori (HR: 0.59; 95% CI: 0.29, 1.20; P-trend = 0.06) in subgroup analysis.

CONCLUSIONS

Meat consumption was not associated with total gastric cancer risk.

Life Cycle Environmental Impacts and Health Effects of Protein-Rich Food as Meat Alternatives: A Review

The food sector is responsible for a considerable impact on the environment in most environmental contexts: the food supply chain causes greenhouse gas emissions, water consumption, reduction in cultivable land, and other environmental impacts. Thus, a change in food supply is required to reduce the environmental impacts caused by the food supply chain and to meet the increasing demand for sufficient and qualitative nutrition. Large herds of livestock are inappropriate to achieve these goals due to the relevant impact of meat supply chain on the environment, e.g., the land used to grow feed for animals is eight times more than that for human nutrition. The search for meat alternatives, especially for the intake of critical nutrients such as protein, is a consequent step. In the above context, this paper summarizes the health aspects of protein-rich food alternatives to meat and carries out a literature review on the life-cycle environmental impacts of this alternative food.

The relationship between processed meat, red meat, and risk of types of cancer: A Mendelian randomization study

Background

Observational studies have suggested processed and red meat may increase the risk of cancer. However, the causal effects and direction between them were still unclear. We conducted two-sample Mendelian randomization (MR) analysis to evaluate the causal effect of processed meat and red meat on the risk of nine common types of cancer, namely, lung, ovarian, endometrial, breast, kidney, gastric, prostate, skin, and oropharyngeal cancer.

Methods

Genome-wide association studies (GWAS) for processed meat and red meat (pork, beef, and mutton) were obtained from the UK Biobank. GWAS of types of cancer in this study were extracted from the genetic consortia and the FinnGen consortium. The inverse variance weighted (IVW) was carried out as the main method for two-sample MR analysis. Sensitivity analyses were used to assess the robustness of the results.

Results

Genetically predicted processed meat intake was causally associated with increased risk of lung cancer (OR [odds ratio] = 1.923, 95% CI = 1.084-3.409, P = 0.025). There is no convincing evidence for the associations between genetically determined processed meat, red meat, and the risk of other cancers we studied.

Conclusion

Our results suggested that intake of processed meat may increase the risk of lung cancer. These findings provided no evidence to support that consumption of processed and red meat has a large effect on the risk of other cancers we studied. Further research is needed to clarify the results.

Processed Meat Consumption and the Risk of Cancer: A Critical Evaluation of the Constraints of Current Evidence from Epidemiological Studies

Based on a large volume of observational scientific studies and many summary papers, a high consumption of meat and processed meat products has been suggested to have a harmful effect on human health. These results have led guideline panels worldwide to recommend to the general population a reduced consumption of processed meat and meat products, with the overarching aim of lowering disease risk, especially of cancer. We revisited and updated the evidence base, evaluating the methodological quality and the certainty of estimates in the published systematic reviews and meta-analyses that examined the association between processed meat consumption and the risk of cancer at different sites across the body, as well as the overall risk of cancer mortality. We further explored if discrepancies in study designs and risks of bias could explain the heterogeneity observed in meta-analyses. In summary, there are severe methodological limitations to the majority of the previously published systematic reviews and meta-analyses that examined the consumption of processed meat and the risk of cancer. Many lacked the proper assessment of the methodological quality of the primary studies they included, or the literature searches did not fulfill the methodological standards needed in order to be systematic and transparent. The primary studies included in the reviews had a potential risk for the misclassification of exposure, a serious risk of bias due to confounding, a moderate to serious risk of bias due to missing data, and/or a moderate to serious risk of selection of the reported results. All these factors may have potentially led to the overestimation of the risk related to processed meat intake across all cancer outcomes. Thus, with the aim of lowering the risk of cancer, the recommendation to reduce the consumption of processed meat and meat products in the general population seems to be based on evidence that is not methodologically strong.

The Mediterranean Diet as a Source of Natural Compounds: Does It Represent a Protective Choice against Cancer?

The Mediterranean diet (MD), characterized by a high intake of fruits, vegetables, legumes, nuts and grains, a moderate intake of red wine and a reduced consumption of meat, has been considered one of the healthiest dietary patterns worldwide. Growing evidence suggests an inverse relationship between high adherence to the MD and cancer, as well as other chronic degenerative diseases. The beneficial effects elicited by the MD pattern on cancer are due to the high contents of bioactive compounds contained in many foods of MD, which protect cells by oxidative and inflammatory processes and inhibit carcinogenesis by targeting the various hallmarks of cancer with different mechanisms of action. Although over the past decades numerous dietary and phytochemical compounds from Mediterranean food that have anticancer potential have been identified, a clear association between the MD eating pattern and cancer needs to be established. While we wait for answers to this question from well-conducted research, the empowering of the MD as a protective choice against cancer should represent the priority for public health policies.

Gastric Cancer Epidemiology

In the United States, the incidence of gastric cancer has decreased over the past five decades. However, despite overall decreasing trends in incidence rates of gastric cancer, rates of noncardia gastric cancer among adults aged less than 50 years in the United States are increasing, and most cases of gastric cancer still present with advanced disease and poor resultant survival. Epidemiologic studies have identified the main risk factors for gastric cancer, including increasing age, male sex, non-White race, Helicobacter pylori infection, and smoking. This article summarizes the current epidemiologic evidence with implications for primary and secondary prevention of gastric cancer.

Indicators and Recommendations for Assessing Sustainable Healthy Diets

Research coupling human nutrition and sustainability concerns is a rapidly developing field, which is essential to guide governments' policies. This critical and comprehensive review analyzes indicators and approaches to "sustainable healthy diets" published in the literature since this discipline's emergence a few years ago, identifying robust gauges and highlighting the flaws of the most commonly used models. The reviewed studies largely focus on one or two domains such as greenhouse gas emissions or water use, while overlooking potential impact shifts to other sectors or resources. The present study covers a comprehensive set of indicators from the health, environmental and socio-economic viewpoints. This assessment concludes that in order to identify the best food option in sustainability assessments and nutrition analysis of diets, some aspects such as the classification and disaggregation of food groups, the impacts of the rates of local food consumption and seasonality, preservation methods, agrobiodiversity and organic food and different production systems, together with consequences for low-income countries, require further analysis and consideration.

Healthfulness Assessment of Recipes Shared on Pinterest: Natural Language Processing and Content Analysis

Background

Although Pinterest has become a popular platform for distributing influential information that shapes users’ behaviors, the role of recipes pinned on Pinterest in these behaviors is not well understood.

Objective

This study aims to explore the patterns of food ingredients and the nutritional content of recipes posted on Pinterest and to examine the factors associated with recipes that engage more users.

Methods

Data were collected from Pinterest between June 28 and July 12, 2020 (207 recipes and 2818 comments). All samples were collected via 2 new user accounts with no search history. A codebook was developed with a raw agreement rate of 0.97 across all variables. Content analysis and natural language processing sentiment analysis techniques were employed.

Results

Recipes using seafood or vegetables as the main ingredient had, on average, fewer calories and less sodium, sugar, and cholesterol than meat- or poultry-based recipes. For recipes using meat as the main ingredient, more than half of the energy was obtained from fat (277/490, 56.6%). Although the most followed pinners tended to post recipes containing more poultry or seafood and less meat, recipes with higher fat content or providing more calories per serving were more popular, having more shared photos or videos and comments. The natural language processing–based sentiment analysis suggested that Pinterest users weighted taste more heavily than complexity (225/2818, 8.0%) and health (84/2828, 2.9%).

Conclusions

Although popular pinners tended to post recipes with more seafood or poultry or vegetables and less meat, recipes with higher fat and sugar content were more user-engaging, with more photo or video shares and comments. Data on Pinterest behaviors can inform the development and implementation of nutrition health interventions to promote healthy recipe sharing on social media platforms.

Towards refining World Cancer Research Fund/American Institute for Cancer Research cancer prevention recommendations for red and processed meat intake: insights from Alberta's Tomorrow Project cohort

Current cancer prevention recommendations advise limiting red meat intake to <500 g/week and avoiding consumption of processed meat, but do not differentiate the source of processed meat. We examined the associations of processed meat derived from red v. non-red meats with cancer risk in a prospective cohort of 26 218 adults who reported dietary intake using the Canadian Diet History Questionnaire. Incidence of cancer was obtained through data linkage with Alberta Cancer Registry with median follow-up of 13·3 (interquartile range (IQR) 5·1) years. Multivariable Cox proportional hazards regression models were adjusted for covariates and stratified by age and sex. The median consumption (g/week) of red meat, processed meat from red meat and processed meat from non-red meat was 267·9 (IQR 269·9), 53·6 (IQR 83·3) and 11·9 (IQR 31·8), respectively. High intakes (4th Quartile) of processed meat from red meat were associated with increased risk of gastrointestinal cancer adjusted hazard ratio (AHR): 1·68 (95 % CI 1·09, 2·57) and colorectal cancers AHR: 1·90 (95 % CI 1·12, 3·22), respectively, in women. No statistically significant associations were observed for intakes of red meat or processed meat from non-red meat. Results suggest that the carcinogenic effect associated with processed meat intake may be limited to processed meat derived from red meats. The findings provide preliminary evidence towards refining cancer prevention recommendations for red and processed meat intake.

On recent meta-analyses of exposure to glyphosate and risk of non-Hodgkin's lymphoma in humans

PURPOSE

A recent meta-analysis of five case-control studies and one cohort study reported that exposure to glyphosate was associated with increased risk of non-Hodgkin's lymphoma (NHL). The meta-analysis was based on estimates of risk from the included studies at the highest reported exposure level obtained from analyses with the longest lag period. The extent to which the summary estimate depends upon the exposure definitions and assumed latency period is uncertain.

METHODS

We carried out sensitivity analyses to determine how the definition of exposure and the choice of latency period affect the summary estimate from meta-analyses of the 6 studies included in the recent meta-analysis. We also conducted a meta-analysis of ever-exposure to glyphosate incorporating the most updated results from the case-control studies.

RESULTS

The summary estimates of risk varied considerably depending on both the assumptions about exposure level and latency. Using the highest reported exposure levels, evidence of an association between glyphosate and NHL was strongest when estimates from analyses in the cohort study with a 20-year lag [RR = 1.41 (95% CI 1.13-1.76)] and a 15-year lag [RR = 1.25 (95% CI 1.01-1.25)] were included. In our meta-analysis of ever-exposure with no lag period, the summary relative risk with updated estimates was 1.05 (95% CI 0.87-1.28).

CONCLUSION

The results of meta-analyses of glyphosate exposure and NHL risk depend on assumptions made about both exposure level and latency period. Our results for ever-exposure are consistent with those of two recent meta-analyses conducted using somewhat different study inclusion criteria.

The complexity of cancer origins at the gastro-oesophageal junction

Chronic acid-biliary reflux and Helicobacter pylori infection are instrumental environmental drivers of cancer initiation and progression in the upper gastrointestinal tract. Remarkably, although these environmental carcinogens are quite dissimilar, the tumour progression cascade these carcinogens engender is highly comparable. For this reason, studies of malignant progression occurring at the anatomic borderland between the oesophagus and the stomach have traditionally lumped junctional adenocarcinomas with either oesophageal adenocarcinoma or gastric adenocarcinoma. Whilst studies have revealed remarkable epidemiological and genetic similarities of these cancers and their associated premalignant conditions, these works have also revealed some key differences. This highlights that further scientific effort demands a dedicated focus on the understanding of the cell-cell interaction between the epithelium and the local microenvironment in this anatomic region. We here review available evidence with regards to tumour progression occurring at the gastro-oesophageal junction and contrast it with available data on cancer evolution in the metaplastic oesophagus and distal stomach.

Adherence to "dietary approaches to stop hypertension" eating plan in relation to gastric cancer

Background

Although adherence to “Dietary Approaches to Stop Hypertension” (DASH) dietary pattern has been linked with reduced risk of several cancers. To our knowledge no studies have examined the association between the DASH dietary pattern and risk of gastric cancer. This study was performed to investigate the association between adherence to the DASH dietary pattern and odds of gastric cancer in Iran.

Methods

This hospital-based case-control study was conducted on 178 histo-pathologically confirmed patients with gastric cancer and 276 sex-matched healthy controls. A validated 146-item Diet History Questionnaire (DHQ) was used to assess participants’ usual dietary intakes. The DASH dietary pattern scores were calculated using the method introduced by Fung. Unconditional logistic regression, in which potential confounders were taken into account, was applied to determine the association of adherence to the DASH dietary pattern and odds of gastric cancer.

Results

Mean age of cases and controls were 60.8 and 53.2 y, respectively. After controlling for age, sex and energy intakes, participants in the highest tertile were 62% less likely to have gastric cancer than those in the lowest tertile (OR 0.38; 95% CI 0.22,0.65; P_trend < 0.004). Further adjustment for other potential confounders, including education, marital status, residential place, alcohol intake and smoking, did not change the association dramatically (OR 0.44; 95% CI 0.25, 0.78; P_trend = 0.005). Even after additional controlling for H-Pylori infection and BMI, greatest adherence to the DASH dietary pattern was associated with a 54% decreased risk of gastric cancer (OR 0.46; 95% CI 0.26, 0.83; P_trend = 0.01).

Conclusions

Adherence to the DASH dietary pattern was associated with lower gastric cancer risk in this case-control study.

The Potential for Plant-Based Diets to Promote Health Among Blacks Living in the United States

Plant-based diets are associated with reduced risks of various chronic diseases in the general population. However, it is unclear how these benefits translate to Blacks living in the United States, who are disproportionately burdened with heart disease, cancer, diabetes, obesity, and chronic kidney disease. The objectives of this study were to: (1) review the general evidence of plant-based diets and health outcomes; (2) discuss how this evidence translates to Blacks following a plant-based diet; and (3) provide recommendations and considerations for future studies in this area. Interestingly, although the evidence supporting plant-based diets in the general population is robust, little research has been done on Blacks specifically. However, the available data suggests that following a plant-based diet may reduce the risk of heart disease and possibly cancer in this population. More research is needed on cardiovascular disease risk factors, cancer subtypes, and other chronic diseases. Further, attention must be given to the unique individual, familial, communal, and environmental needs that Blacks who follow plant-based diets may have. Interventions must be culturally appropriate in order to achieve long-term success, and providing low-cost, flavorful, and nutritious options will be important.

Reduction of Red and Processed Meat Intake and Cancer Mortality and Incidence: A Systematic Review and Meta-analysis of Cohort Studies

This article has been corrected. The original version (PDF) is appended to this article as a Supplement.

BACKGROUND

Cancer incidence has continuously increased over the past few centuries and represents a major health burden worldwide.

PURPOSE

To evaluate the possible causal relationship between intake of red and processed meat and cancer mortality and incidence.

DATA SOURCES

Embase, Cochrane Central Register of Controlled Trials, Web of Science, CINAHL, and ProQuest from inception until July 2018 and MEDLINE from inception until April 2019 without language restrictions.

STUDY SELECTION

Cohort studies that included more than 1000 adults and reported the association between consumption of unprocessed red and processed meat and cancer mortality and incidence.

DATA EXTRACTION

Teams of 2 reviewers independently extracted data and assessed risk of bias; 1 reviewer evaluated the certainty of evidence, which was confirmed or revised by the senior reviewer.

DATA SYNTHESIS

Of 118 articles (56 cohorts) with more than 6 million participants, 73 articles were eligible for the dose-response meta-analyses, 30 addressed cancer mortality, and 80 reported cancer incidence. Low-certainty evidence suggested that an intake reduction of 3 servings of unprocessed meat per week was associated with a very small reduction in overall cancer mortality over a lifetime. Evidence of low to very low certainty suggested that each intake reduction of 3 servings of processed meat per week was associated with very small decreases in overall cancer mortality over a lifetime; prostate cancer mortality; and incidence of esophageal, colorectal, and breast cancer.

LIMITATION

Limited causal inferences due to residual confounding in observational studies, risk of bias due to limitations in diet assessment and adjustment for confounders, recall bias in dietary assessment, and insufficient data for planned subgroup analyses.

CONCLUSION

The possible absolute effects of red and processed meat consumption on cancer mortality and incidence are very small, and the certainty of evidence is low to very low.

PRIMARY FUNDING SOURCE

None. (PROSPERO: CRD42017074074).

Processed meat intake and chronic disease morbidity and mortality: An overview of systematic reviews and meta-analyses

Despite the nutritional value of meat, a large volume of reviews and meta-analyses suggests that processed meat intake is associated with an increased risk of chronic diseases. However, assessments of the quality of these published reviews internal validity are generally lacking. We systematically reviewed and assessed the quality alongside summarizing the results of previously published systematic reviews and meta-analyses that examined the association between processed meat intake and cancers, type II diabetes (T2D), and cardiovascular diseases (CVD). Reviews and meta-analyses published until May 2018 were identified through a systematic literature search in the databases MEDLINE and EMBASE, and reference lists of included reviews. The quality of the systematic reviews and meta-analyses was assessed using A Measurement Tool to Assess Systematic Reviews (AMSTAR). All eligible reviews had to comply with two quality requirements: providing sufficient information on quality assessment of the primary studies and a comprehensive search. The results were summarized for T2D, CVD, and each of the different cancer types. The certainty in the estimates of the individual outcomes was rated using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) method. In total, 22 systematic reviews were eligible and thus included in this review. More than 100 reviews were excluded because quality assessment of the primary studies had not been performed. The AMSTAR score of the included reviews ranged from 5 to 8 indicating moderate quality. Overall, the quality assessments of primary studies of the reviews are generally lacking; the scientific quality of the systematic reviews reporting positive associations between processed meat intake and risk of various cancers, T2D and CVD is moderate, and the results from case-control studies suggest more often a positive association than the results from cohort studies. The overall certainty in the evidence was very low across all individual outcomes, due to serious risk of bias and imprecision.

The Influence of Red Meat on Colorectal Cancer Occurrence Is Dependent on the Genetic Polymorphisms of S-Glutathione Transferase Genes

BACKGROUND

It is postulated that both individual genotype and environmental factors such as diet may modify the risk of developing colorectal cancer (CRC). The influences of GST gene polymorphism and red meat intake on CRC occurrence in the Polish population were analyzed in this study.

METHODS

Genotyping was performed with the qPCR method.

RESULTS

A high frequency of meat consumption was associated with an over 2-fold increase in the risk of colorectal cancer odds ratio (OR) adjusted for sex and age = 2.4, 95% confidence interval (CI); 1.3-4.4). However, after analyzing the genetic profiles, in the absence of polymorphisms of all three analyzed genes, there was no association between a high frequency of meat consumption and the occurrence of CRC. In the case of GSTM1 gene polymorphism, the high frequency of meat consumption increased the risk of CRC by almost more than 4 times (OR adjusted for sex and age = 3.8, 95% CI: 1.6-9.1). For GSTP1 gene polymorphism, a 3-fold increase in CRC risk was observed with a high frequency of meat consumption (OR adjusted for sex and age = 3.4, 95% CI: 1.4-8.1). In the case of GSTT1 gene polymorphism, the increase in risk of CRC was not statistically significant (OR adjusted for sex and age = 1.9, 95% CI: 0.4-8.5).

CONCLUSIONS

The frequency of red meat intake in non-smokers increases the risk of colon cancer in the case of GST gene polymorphisms.

Effect of Red, Processed, and White Meat Consumption on the Risk of Gastric Cancer: An Overall and Dose⁻Response Meta-Analysis

Whether the risk of gastric cancer varies by the types of meat consumption still remains disputable. The purpose of this meta-analysis was to identify the exact associations that red, processed, and white meat have with gastric cancer. We searched relevant studies in Medline, EMBASE, and the Cochrane Library before November 2018, including cohort and case-control studies. We used random-effect models to estimate the adjusted relative risk (RR), and Egger’s tests to evaluate publication bias. Through stepwise screening, 43 studies were included in this analysis (11 cohort studies and 32 case-control studies with 16,572 cases). In a meta-analysis for the highest versus lowest categories of meat consumption, both red (RR: 1.41, 95% confidence interval (CI): 1.21–1.66) and processed (RR: 1.57, 95% CI: 1.37–1.81) meat consumption were positively associated with gastric cancer risk, while white meat consumption was negatively associated with gastric cancer risk (RR: 0.80, 95% CI: 0.69–0.92). In a dose–response meta-analysis, the RRs of gastric cancer were 1.26 (95% CI: 1.11–1.42) for every 100 g/day increment in red meat consumption, 1.72 (95% CI: 1.36–2.18) for every 50 g/day increment in processed meat consumption, and 0.86 (95% CI: 0.64–1.15) for every 100 g/day increment in white meat consumption. The increase of white meat consumption may reduce the risk of gastric cancer, while red or processed meat may increase the risk of gastric cancer. Further studies are required to identify these associations, especially between white meat and gastric cancer.

Nicotinamide N-methyltransferase promotes epithelial-mesenchymal transition in gastric cancer cells by activating transforming growth factor-β1 expression

Previous studies have demonstrated that nicotinamide N-methyltransferase (NNMT) is aberrantly expressed in a number of tumors. In the present study, it was demonstrated that the gene and protein levels of NNMT were significantly increased in gastric cancer cells. Furthermore, upregulation of NNMT significantly increased the expression of mesenchymal markers, including α-smooth muscle actin (SMA), vimentin and fibronectin, but decreased the levels of epithelial cadherin. Since transforming growth factor (TGF)-β1 may serve a key function in epithelial-mesenchymal transition (EMT), the effects of NNMT on the expression of TGF-β1 were investigated in BGC-823 cells. The results demonstrated that overexpression of NNMT significantly induced the expression of TGF-β1. However, knockdown of NNMT inhibited the expression of TGF-β1, mothers against decapentaplegic homolog (Smad)2 and α-SMA. Additionally, pre-incubation with TGF-β1 partially eliminated NNMT-mediated changes in EMT. Collectively, the results demonstrated that upregulation of NNMT in gastric cancer cells may increase the expression of TGF-β1, therefore activating TGF-β1/Smad signaling, which in turn promotes EMT.

The Role of Red Meat and Flavonoid Consumption on Cancer Prevention: The Korean Cancer Screening Examination Cohort

Markedly increased red meat consumption is a cancer risk factor, while dietary flavonoids may help prevent the disease. The purpose of this study was to investigate the associations of red meat and flavonoid consumption with cancer risk, based on data from 8024 subjects, drawn from the 2004–2008 Cancer Screening Examination Cohort of the Korean National Cancer Center. Hazard ratios (HRs) were obtained by using a Cox proportional hazard model. During the mean follow-up period of 10.1 years, 443 cases were newly diagnosed with cancer. After adjusting for age, there was a significant correlation between cancer risk and the daily intake of ≥43 g of red meat per day (HR 1.31; 95% CI 1.01, 1.71; p = 0.045), and total flavonoid intake tended to decrease cancer risk (HR 0.70; 95% CI 0.49, 0.99; highest vs. lowest quartile; p-trend = 0.073) in men. Following multivariable adjustment, there were no statistically significant associations between flavonoid intake and overall cancer risk in individuals with high levels of red meat intake. Men with low daily red meat intake exhibited an inverse association between flavonoid consumption and cancer incidence (HR 0.41; 95% CI 0.21, 0.80; highest vs. lowest; p-trend = 0.017). Additional research is necessary to clarify the effects of flavonoid consumption on specific cancer incidence, relative to daily red meat intake.