Citizen science in environmental health research: A comparison with conventional approaches and creation of a guidance tool issued from the LILAS initiative.

CONTEXT: Public interest for citizen science (CS) in environmental health is growing. The goals of environmental health research projects are diverse, as are the methods used to reach these goals. Opportunities for greater implication of the civil society and related challenges differ at each step of such projects. These methodological aspects need to be widely shared and understood by all stakeholders. The LILAS initiative (acronym for "application of citizen science approaches such as LIving LAbS to research on environmental exposures and chronic risks") aimed to 1) favor a mutual understanding of the main issues and research methods in environmental health, of their stakes for different actors, but also of the requirements, strengths and limitations of these methods and to 2) identify expected benefits and points of attention related to stronger degrees of participation as part of environmental health research projects. METHODS: The LILAS initiative gathered institutional researchers, academics and civil society representatives interested in environmental exposures. Five meetings allowed to collectively identify different types of environmental health research studies and reflect about the benefits, limitations, and methodological issues related to the introduction of growing citizen participation as part of such studies. An analytic table matrix summarizing these aspects was co-created and filled by participants, as a tool devoted to help stakeholders with the definition of future CS research projects in environmental health. RESULTS: For different fields of research (e.g.: studies for assessment of environmental exposures, interventions on these exposures, quantitative risk assessment, epidemiological studies), the matrix lists expected benefits for various stakeholders, the fundamental principles of research methods and related practical constraints, but also advantages and limitations related to the use of CS or conventional research approaches. CONCLUSION: The LILAS initiative allowed to develop a tool which provides consolidated grounds for the co-creation of research projects on environmental exposures involving CS.

The Mediterranean diet: health, science and society.

The Mediterranean diet (MD) emerged as a healthy food regimen long before it could be recognised which nutrients or foods were responsible for its observed benefits, and it was only in the middle of the last century that the first scientific approach 'The Seven Countries Study' appeared. Epidemiological and anthropological studies of the MD converged, first by investigating at single nutrients or foods, then by adopting the more holistic approach of dietary patterns (DP), and now with a molecular approach. These studies resulted in convincing evidence that a MD decreases the risk of all-cause mortality and cardiovascular mortality and incidence. A risk reduction of developing type 2 diabetes is probable. Evidence is less stringent for other metabolic diseases and all cancers but from possible to probable for some cancer sites. Although DP showed that the MD has to be considered in its totality, olive oil could have a specific role. Lifestyle factors such as physical activity for energy balance, outdoor life for vitamin D synthesis and conviviality are also probably partly responsible for the health benefits. The MD is a lifestyle well suited for coping not only with personal health but also with wider societal concerns in relation to environment, public health and economy.

Can rapeseed oil replace olive oil as part of a Mediterranean-style diet?

The present narrative review compares evidence from experimental, epidemiological and clinical studies of the health benefits of rapeseed oil (RO) (known as canola oil) and olive oil (OO) in order to assess whether rapeseed oil is suitable as a sustainable alternative to OO as part of a Mediterranean-style diet in countries where olive trees do not grow. From epidemiological studies, the evidence for cardiovascular protection afforded by extra-virgin OO is 'convincing', and for cancers 'limited-suggestive', especially oestrogen receptor-negative breast cancer, but more studies are required in relation to cognitive impairment. Evidence for RO is limited to short-term studies on the biomarkers of risk factors for CVD. Any benefits of RO are likely to be due to α-linolenic acid; however, it is prone to oxidation during frying. We conclude that due to a lack of evidence from observational or intervention studies indicating that RO has comparable health benefits to extra-virgin OO, RO cannot currently be recommended as a suitable substitute for extra-virgin OO as part of a Mediterranean-style diet.

Omega-3 fatty acids and cancers: a systematic update review of epidemiological studies.

Experimental models showed consistently a modulation of carcinogenesis by omega 3 polyunsaturated fatty acids (ω3 PUFA). Fish intake is often described as part of a beneficial dietary pattern. However, observational epidemiological studies on the relationship between ω3 PUFA reported conflicting results. The objective of this systematic review is to determine whether there exists any progress in the evaluation of the causal relationship between dietary ω3 PUFA and cancers since the previous FAO/OMS expert consultation and whether it is possible to propose preventive and/or adjuvant therapeutic recommendations. Prospective and case-control observational studies published since 2007 and meeting validity criteria were considered together with RCT. Experimental studies are mentioned to provide for biological plausibility. When evaluating the level of evidence, a portfolio approach was used, weighted by a hierarchy giving higher importance to prospective studies followed by RCT if any. There is a probable level of evidence that ALA per se is neither a risk factor nor a beneficial factor with regards to cancers. Observational studies on colorectal, prostate and breast cancers only provided limited evidence suggesting a possible role of LC-ω3PUFA in cancer prevention because insufficient homogeneity of the observations. Explanation for heterogeneity might be the inherent difficulties associated with epidemiology (confounding and dietary pattern context, measurement error, level of intake, genetic polymorphism). The role of LC-ω3PUFA as adjuvant, might be considered of possible use, in view of the latest RCT on lung cancers even if RCT on other cancers still need to be undertaken.

Alcohol and genetic polymorphisms: effect on risk of alcohol-related cancer.

Public health guidelines aim to limit the consumption of alcoholic beverages worldwide and the subsequent health burden. In particular, alcohol consumption is an avoidable risk factor for cancer. In human beings, ethanol in alcoholic drinks is mainly oxidised in the liver by alcohol dehydrogenases to acetaldehyde, and is further detoxified to acetate by aldehyde dehydrogenases. Functional variants in genes involved in alcohol metabolism result in differences between individuals in exposure to carcinogenic acetaldehyde, suggesting a possible interaction of genetic susceptibility and alcohol exposure in cancer. We reviewed available studies of the combined effects of alcohol drinking and genetic polymorphisms on alcohol-related cancer risk. Most available data were for polymorphisms in alcohol and folate metabolism. We give an overview of published studies on the combined effects of alcohol drinking and polymorphisms in genes for alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), cytochrome P450 2E1, and methylene-tetrahydrofolate reductase on the risk of alcohol-related cancer. Current data lend support to a role of polymorphisms ADH1B and ALDH2 combined with alcohol consumption in cancer. Other available data are insufficient or inconclusive, highlighting the need for additional studies.

Dietary intakes of omega-6 and omega-3 polyunsaturated fatty acids and the risk of breast cancer.

Experimental studies suggest detrimental effects of omega-6 polyunsaturated fatty acids (PUFA), and beneficial effects of omega-3 PUFAs on mammary carcinogenesis, possibly in interaction with antioxidants. However, PUFA food sources are diverse in human diets and few epidemiologic studies have examined whether associations between dietary PUFAs and breast cancer risk vary according to food sources or antioxidant intakes. The relationship between individual PUFA intakes estimated from diet history questionnaires and breast cancer risk was examined among 56,007 French women. During 8 years of follow-up, 1,650 women developed invasive breast cancer. Breast cancer risk was not related to any dietary PUFA overall; however, opposite associations were seen according to food sources, suggesting other potential effects than PUFA per se. Breast cancer risk was inversely associated with alpha-linolenic acid (ALA) intake from fruit and vegetables [highest vs. lowest quintile, hazard ratio (HR) 0.74; 95% confidence interval (CI) 0.63, 0.88; p trend < 0.0001], and from vegetable oils (HR 0.83; 95% CI 0.71, 0.97; p trend 0.017). Conversely, breast cancer risk was positively related to ALA intake from nut mixes (p trend 0.004) and processed foods (p trend 0.068), as was total ALA intake among women in the highest quintile of dietary vitamin E (p trend 0.036). A significant interaction was also found between omega-6 and long-chain omega-3 PUFAs, with breast cancer risk inversely related to long-chain omega-3 PUFAs in women belonging to the highest quintile of omega-6 PUFAs (p interaction 0.042). These results emphasize the need to consider food sources, as well as interactions between fatty acids and with antioxidants, when evaluating associations between PUFA intakes and breast cancer risk.

French Recommendations for Sugar Intake in Adults: A Novel Approach Chosen by ANSES.

This article presents a systematic review of the scientific evidence linking sugar consumption and health in the adult population performed by a group of experts, mandated by the French Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement, et du travail (ANSES). A literature search was performed by crossing search terms for overweight/obesity, diabetes/insulin resistance, dyslipidemia/cardiovascular diseases, non-alcoholic fatty liver diseases (NAFLD), and uric acid concentrations on one hand and for intake of sugars on the other. Controlled mechanistic studies, prospective cohort studies, and randomized clinical trials were extracted and assessed. A literature analysis supported links between sugar intake and both total energy intake and body weight gain, and between sugar intake and blood triglycerides independently of total energy intake. The effects of sugar on blood triglycerides were shown to be mediated by the fructose component of sucrose and were observed with an intake of fructose >50 g/day. In addition, prospective cohort studies showed associations between sugar intake and the risk of diabetes/insulin resistance, cardiovascular diseases, NAFLD, and hyperuricemia. Based on these observations, ANSES proposed to set a maximum limit to the intake of total sugars containing fructose (sucrose, glucose⁻fructose syrups, honey or other syrups, and natural concentrates, etc.) of 100 g/day.

Nutrient intake in an elderly population in southern France (POLANUT): deficiency in some vitamins, minerals and omega-3 PUFA.

OBJECTIVE: Evaluation of the nutritional status of an elderly cohort from a French Mediterranean area. DESIGN: Cross-sectional nutritional assessment in the framework of the population-based POLA cohort. SUBJECTS AND METHODS: 832 subjects aged 70 years or older answered a 165-item, semi-quantitative food frequency questionnaire. Mean Nutritional Need (MNN) was defined as 77% of the French Recommended Daily Allowance (RDA). The risk for clinical deficiency (CD) was defined as intakes lower than the Limit Threshold Intake (70% of the MNN). RESULTS: Consumption was characterized by an excess of saturated fatty acids (SFA) (95.4% of subjects above the RDA) and a deficit of omega-3 polyunsaturated fatty acids (PUFA) (60.1% and 46.9% of subjects at risk for CD for alpha-linolenic (ALA) and long-chain omega-3 PUFA, respectively). Median intakes of fiber, vitamins B6, B9, and D, calcium, and magnesium were below the RDA. Dairy products were the first providers of SFA, nuts of ALA, and fish of long-chain omega-3 PUFA and vitamin D. CONCLUSION: The study identified an unbalanced food intake, with an excess of mammal animal products, mainly of dairy products, and a deficit of fish and vegetal foods. This resulted in a deficiency in some vitamins, minerals, and omega-3 PUFA.

The Medi-RIVAGE study: reduction of cardiovascular disease risk factors after a 3-mo intervention with a Mediterranean-type diet or a low-fat diet.

BACKGROUND: Epidemiologic studies link Mediterranean-type diets to a low incidence of cardiovascular disease; however, few dietary intervention studies have been undertaken, especially in primary prevention. OBJECTIVES: In the Mediterranean Diet, Cardiovascular Risks and Gene Polymorphisms (Medi-RIVAGE) study, the effects of a Mediterranean-type diet (Med group) or a low-fat diet (low-fat group) on risk factors were evaluated in 212 volunteers (men and women) with moderate risk factors for cardiovascular disease. DESIGN: After the 3-mo dietary intervention, changes in many risk factors were evaluated. Dietary questionnaires and plasma nutritional markers were used to test compliance. RESULTS: Although the dietary goals were only partially reached, changes in dietary habits were observed in both groups (n = 169): protein, carbohydrate, and fiber intakes increased and fat quality (decreased saturated fat and increased monounsaturated or polyunsaturated fat) improved. BMI, total and triacylglycerol-rich lipoprotein (TRL) cholesterol, triacylglycerols, TRL triacylglycerols, apolipoproteins A-I and B, insulinemia, glycemia, and the homeostasis model assessment score were significantly lower after 3 mo. The reductions in total cholesterol, triacylglycerols, and insulinemia remained significant after adjustment for BMI. There was a trend for a diet-by-time interaction for LDL cholesterol (P = 0.09). Our data predicted a 9% reduction in cardiovascular disease risk with the low-fat diet and a 15% reduction with this particular Mediterranean diet. CONCLUSION: After a 3-mo intervention, both diets significantly reduced cardiovascular disease risk factors to an overall comparable extent.

Food Processing and the Mediterranean Diet.

The benefits of the Mediterranean diet (MD) for protecting against chronic disorders such as cardiovascular disease are usually attributed to high consumption of certain food groups such as vegetables, and low consumption of other food groups such as meat. The influence of food processing techniques such as food preparation and cooking on the nutrient composition and nutritional value of these foods is not generally taken into consideration. In this narrative review, we consider the mechanistic and epidemiological evidence that food processing influences phytochemicals in selected food groups in the MD (olives, olive oil, vegetables and nuts), and that this influences the protective effects of these foods against chronic diseases associated with inflammation. We also examine how the pro-inflammatory properties of meat consumption can be modified by Mediterranean cuisine. We conclude by discussing whether food processing should be given greater consideration, both when recommending a MD to the consumer and when evaluating its health properties.