Establishing What Constitutes a Healthy Human Gut Microbiome: State of the Science, Regulatory Considerations, and Future Directions.

On December 17, 2018, the North American branch of the International Life Sciences Institute (ILSI North America) convened a workshop "Can We Begin to Define a Healthy Gut Microbiome Through Quantifiable Characteristics?" with >40 invited academic, government, and industry experts in Washington, DC. The workshop objectives were to 1) develop a collective expert assessment of the state of the evidence on the human gut microbiome and associated human health benefits, 2) see if there was sufficient evidence to establish measurable gut microbiome characteristics that could serve as indicators of "health," 3) identify short- and long-term research needs to fully characterize healthy gut microbiome-host relationships, and 4) publish the findings. Conclusions were as follows: 1) mechanistic links of specific changes in gut microbiome structure with function or markers of human health are not yet established; 2) it is not established if dysbiosis is a cause, consequence, or both of changes in human gut epithelial function and disease; 3) microbiome communities are highly individualized, show a high degree of interindividual variation to perturbation, and tend to be stable over years; 4) the complexity of microbiome-host interactions requires a comprehensive, multidisciplinary research agenda to elucidate relationships between gut microbiome and host health; 5) biomarkers and/or surrogate indicators of host function and pathogenic processes based on the microbiome need to be determined and validated, along with normal ranges, using approaches similar to those used to establish biomarkers and/or surrogate indicators based on host metabolic phenotypes; 6) future studies measuring responses to an exposure or intervention need to combine validated microbiome-related biomarkers and/or surrogate indicators with multiomics characterization of the microbiome; and 7) because static genetic sampling misses important short- and long-term microbiome-related dynamic changes to host health, future studies must be powered to account for inter- and intraindividual variation and should use repeated measures within individuals

A meta-analysis of individual participant data reveals an association between circulating levels of IGF-I and prostate cancer risk

The role of insulin-like growth factors (IGF) in prostate cancer development is not fully understood. To investigate the association between circulating concentrations of IGFs (IGF-I, IGF-II, IGFBP-1, IGFBP-2, and IGFBP-3) and prostate cancer risk, we pooled individual participant data from 17 prospective and two cross-sectional studies, including up to 10,554 prostate cancer cases and 13,618 control participants. Conditional logistic regression was used to estimate the ORs for prostate cancer based on the study-specific fifth of each analyte. Overall, IGF-I, IGF-II, IGFBP-2, and IGFBP-3 concentrations were positively associated with prostate cancer risk (Ptrend all ≤ 0.005), and IGFBP-1 was inversely associated weakly with risk (Ptrend = 0.05). However, heterogeneity between the prospective and cross-sectional studies was evident (Pheterogeneity = 0.03), unless the analyses were restricted to prospective studies (with the exception of IGF-II, Pheterogeneity = 0.02). For prospective studies, the OR for men in the highest versus the lowest fifth of each analyte was 1.29 (95% confidence interval, 1.16-1.43) for IGF-I, 0.81 (0.68-0.96) for IGFBP-1, and 1.25 (1.12-1.40) for IGFBP-3. These associations did not differ significantly by time-to-diagnosis or tumor stage or grade. Aftermutual adjustment for each of the other analytes, only IGF-I remained associated with risk. Our collaborative study represents the largest pooled analysis of the relationship between prostate cancer risk and circulating concentrations of IGF-I, providing strong evidence that IGF-I is highly likely to be involved in prostate cancer development.</p

Nutritional quality of food as represented by the FSAm-NPS nutrient profiling system underlying the Nutri-Score label and cancer risk in Europe: results from the EPIC prospective cohort study

Background: Helping consumers make healthier food choices is a key issue for the prevention of cancer and other diseases. In many countries, political authorities are considering the implementation of a simplified labelling system to reflect the nutritional quality of food products. The Nutri-Score, a five-colour nutrition label, is derived from the Nutrient Profiling System of the British Food Standards Agency (modified version) (FSAm-NPS). How the consumption of foods with high/low FSAm-NPS relates to cancer risk has been studied in national/regional cohorts but has not been characterized in diverse European populations. Methods and Findings: This prospective analysis included 471,495 adults from the European Prospective Investigation into Cancer and Nutrition (EPIC, 1992–2014, median follow-up: 15.3 y), among whom there were 49,794 incident cancer cases (main locations: breast, n = 12,063; prostate, n = 6,745; colon-rectum, n = 5,806). Usual food intakes were assessed with standardized country-specific diet assessment methods. The FSAm-NPS was calculated for each food/beverage using their 100-g content in energy, sugar, saturated fatty acid, sodium, fibres, proteins, and fruits/vegetables/legumes/nuts. The FSAm-NPS scores of all food items usually consumed by a participant were averaged to obtain the individual FSAm-NPS Dietary Index (DI) scores. Multi-adjusted Cox proportional hazards models were computed. A higher FSAm-NPS DI score, reflecting a lower nutritional quality of the food consumed, was associated with a higher risk of total cancer (HRQ5 versus Q1 = 1.07; 95% CI 1.03–1.10, P-trend < 0.001). Absolute cancer rates in those with high and low (quintiles 5 and 1) FSAm-NPS DI scores were 81.4 and 69.5 cases/10,000 person-years, respectively. Higher FSAm-NPS DI scores were specifically associated with higher risks of cancers of the colon-rectum, upper aerodigestive tract and stomach, lung for men, and liver and postmenopausal breast for women (all P < 0.05). The main study limitation is that it was based on an observational cohort using self-reported dietary data obtained through a single baseline food frequency questionnaire; thus, exposure misclassification and residual confounding cannot be ruled out. Conclusions: In this large multinational European cohort, the consumption of food products with a higher FSAm-NPS score (lower nutritional quality) was associated with a higher risk of cancer. This supports the relevance of the FSAm-NPS as underlying nutrient profiling system for front-of-pack nutrition labels, as well as for other public health nutritional measures

Nutri-Score and NutrInform Battery: Effects on Performance and Preference in Italian Consumers

In May 2020, the European Commission announced a proposal for a mandatory front-of-pack label (FoPL) for all European Union (EU) countries. Indeed, FoPLs have been recognized by several public institutions as a cost-effective measure to guide consumers toward nutritionally favorable food products. The aim of this study was to compare the performance and consumer preference of two FoPLs currently proposed or implemented in EU countries, the interpretive format Nutri-Score and the non-interpretive format NutrInform Battery, among Italian consumers. The experimental study was conducted in 2021 on a representative sample of 1064 Italian adults (mean age = 46.5 +/- 14.1 years; 48% men). Participants were randomized to either Nutri-Score or NutrInform and had to fill out an online questionnaire testing their objective understanding of the FoPL on three food categories (breakfast products, breakfast cereals and added fats) as well as purchase intention, subjective understanding and perception. Multivariable logistic regressions and t-tests were used to analyze the answers. In terms of the capacity of participants to identify the most nutritionally favorable products, Nutri-Score outperformed NutrInform in all food categories, with the highest odds ratio being observed for added fats (OR = 21.7 [15.3-31.1], p &lt; 0.0001). Overall, with Nutri-Score, Italian participants were more likely to intend to purchase nutritionally favorable products than with NutrInform (OR = 5.29 [4.02-6.97], p &lt; 0.0001). Focusing on olive oil, participants of the Nutri-Score group had higher purchase intention of olive oil compared to those in the NutrInform group (OR = 1.92 [1.42-2.60], p &lt; 0.0001) after manipulating the label. The interpretive format Nutri-Score appears to be a more efficient tool than NutrInform for orienting Italian consumers towards more nutritionally favorable food choices

Is the number of ideal cardiovascular health metrics in midlife associated with lower risk of cancer? Evidence from 3 European prospective cohorts

BACKGROUND: Primordial prevention may be a relevant strategy for the prevention of cancer. Given the commonality of risk factors and mechanisms between cancer and cardiovascular disease, we examined the associations between the number of ideal cardiovascular health metrics in midlife and incident cancer. METHODS: In 3 European cohorts (NutriNet-Santé and GAZEL, France; Whitehall II, United Kingdom), the number of ideal cardiovascular health metrics was determined at baseline (range 0-7). Follow-up for cancer events was until October 2020 (NutriNet-Santé), March 2017 (Whitehall II) and December 2015 (GAZEL). Cox regression was conducted in each cohort, and results were thereafter pooled using a random-effects model. RESULTS: Data were available on 39 718 participants. A total of 16 237 were from NutriNet-Santé (mean age 51.3 yr; 28% men), 9418 were from Whitehall II (mean age 44.8 yr; 68% men) and 14 063 were from GAZEL (mean age 45.2 yr; 75% men). The median follow-up was 8.1 years in NutriNet-Santé, 29.6 years in Whitehall II and 24.8 years in GAZEL, and yielded a total of 4889 cancer events. A greater number of ideal cardiovascular health metrics was associated with a lower overall cancer risk in each cohort, with an aggregate hazard ratio (HR) per 1 increment in number of ideal metrics of 0.91 (95% confidence interval [CI] 0.88-0.93). This association remained after removal of the smoking metric (aggregate HR per unit increment in number of ideal metrics: 0.94, 95% CI 0.90-0.97), and site-specific analysis demonstrated a significant association with lung cancer. INTERPRETATION: A greater number of ideal cardiovascular health metrics in midlife was associated with lower cancer risk, notably lung cancer. Primordial prevention of cardiovascular risk factors in midlife may be a complementary strategy to prevent the onset of cancer

Nutritional quality of diet characterized by the Nutri-Score profiling system and cardiovascular disease risk: a prospective study in 7 European countries

BackgroundNutri-Score is a scientifically validated 5-color front-of-pack nutrition label reflecting the nutrient profile of foods. It has been implemented in several European countries on a voluntary basis, pending the revision of the European labeling regulation. Hence, scientific evidence is needed regarding the ability of the nutrient profile underlying the Nutri-Score (uNS-NPS, 2023-updated version) to characterize healthier foods. Our objective was therefore to study the prospective association between the nutritional quality of diet characterized by the uNS-NPS and the risk of cardiovascular diseases in a large European population.MethodsOur analyses included 345,533 participants from the European Prospective Investigation into Cancer and Nutrition study (EPIC, 1992-2010, 7 European countries). Food intakes were assessed at baseline using country-specific dietary questionnaires. The uNS-NPS was calculated as a continuous scale for each food, based on its 100 g content of energy, sugars, saturated fatty acids, salt, fibre, and protein and percentage content of fruit, vegetables, and pulses. A dietary index was derived at the individual level (uNS-NPS DI: energy-weighted mean of uNS-NPS scores of all foods consumed by a participant). Cardiovascular events during follow-up were retrieved using country-specific methods (self-report, registry data). Multi-adjusted Cox models were computed.FindingsOverall, 16,214 first cardiovascular events were reported (median follow-up: 12.3 years; 4,103,133 person-years). The consumption of foods with a higher uNS-NPS score (reflecting a lower overall nutritional quality of diet) was associated with higher risks of total cardiovascular events (Hazards Ratio (HR) for an increment of 1 standard deviation: 1.03 (95% Confidence Interval 1.01-1.05)), especially myocardial infarction (HR = 1.03 (1.01-1.07)), and stroke (HR = 1.04 (1.01-1.07)).InterpretationIn this large prospective study among European adults, a higher risk of cardiovascular diseases (total and several subtypes) was observed in individuals consuming a diet with a lower nutritional value, as graded by the uNS-NPS score. This brings new evidence on the relevance of the updated nutrient profile underlying the Nutri-Score to characterize foods with a healthier nutrient profile.FundingEPIC-CVD was supported by EU FP7, ERC, UK MRC, British Heart Foundation, and UK NIHR

Consumption of dairy products and cardiovascular disease risk: results from the French prospective cohort NutriNet-Santé

In France, dairy products contribute to dietary saturated fat intake, of which reduced consumption is often recommended for cardiovascular disease (CVD) prevention. Epidemiological evidence on the association between dairy consumption and CVD risk remains unclear, suggesting either null or inverse associations. This study aimed to investigate the associations between dairy consumption (overall and specific foods) and CVD risk in a large cohort of French adults. This prospective analysis included participants aged ≥ 18 years from the NutriNet-Santé cohort (2009–2019). Daily dietary intakes were collected using 24h-dietary records. Total dairy, milk, cheese, yogurts, fermented and reduced-fat dairy intakes were investigated. CVD cases (n=1,952) included cerebrovascular (n=878 cases) and coronary heart diseases (CHD, n=1,219 cases). Multivariable Cox models were performed to investigate associations. This analysis included n=104,805 French adults (mean age at baseline 42.8 years (SD 14.6), mean follow-up 5.5 years (SD 3.0, i.e. 579,155 persons years). There were no significant associations between dairy intakes and total CVD or CHD risks. However, the consumption of at least 160 g/d of fermented dairy (e.g. cheese and yogurts) was associated with a reduced risk of cerebrovascular diseases compared to intakes below 57 g/d (HR=0.81 [0.66-0.98], p-trend=0.01). Despite being a major dietary source of saturated fats, dairy consumption was not associated with CVD or CHD risks in this study. However, fermented dairy was associated with a lower cerebrovascular disease risk. Robust randomized controlled trials are needed to further assess the impact of consuming different dairy foods on CVD risk and potential underlying mechanisms

Co-benefits from sustainable dietary shifts for population and environmental health: an assessment from a large European cohort study

Background: Unhealthy diets, the rise of non-communicable diseases, and the declining health of the planet are highly intertwined, where food production and consumption are major drivers of increases in greenhouse gas (GHG) emissions, substantial land use, (LU) and adverse health outcomes such as cancer and mortality. Methods: In the European Prospective Investigation into Cancer and Nutrition (EPIC), a multi-centre prospective cohort study (n=443,991), we estimated associations between dietary contributions to GHG emissions and LU and all-cause and cause-specific mortality and incident cancers using Cox proportional-hazard regression models. Co-benefits, encompassing the potential effects of alternative diets on all-cause mortality and cancer and potential reduction in GHG emissions and LU, were estimated using counterfactual attributable fraction (AF) intervention models, simulating potential effects from dietary shifts based on the EAT-Lancet reference diet. Findings: There was an association between levels of dietary-based GHG emissions and LU and all-cause mortality, with a Hazard Ratio and 95% Confidence Interval (CI) of 1.13 (1.10, 1.16) and 1.18 (95% CI: 1.15, 1.21), respectively, comparing the fourth quartile to the first (HRQ4 vs Q1). Similar associations were observed for cause-specific mortality. There were also associations between overall cancer rates and GHG emissions (HRQ4 vs Q1: 1.11, 95% CI: 1.09, 1.14) and LU (HRQ4 vs Q1: 1.13, 95% CI: 1.10, 1.15); however, estimates differed by cancer type. Through counterfactual AF modelling of shifts in diets, we find that between 19 to 63% of deaths and 10 to 39% of cancers could be prevented, over a 20-year risk period, from adhering to different scores of the EAT-Lancet reference diet. Additionally, switching from a lower score of the EAT-Lancet reference diet to a higher score could reduce food-associated GHG and LU levels by 50% and 62%, respectively. Interpretation: Our results support shifts in diets that could lead to co-benefits, minimizing dietary related GHG emissions and LU, to reduce environmental footprints, aiding in climate change mitigation, and improving population health