This review discusses the inconsistent recommendations on alcohol consumption and its association with chronic disease, highlighting the need for an evidence-based consensus. Alcohol is an addictive substance consumed worldwide, especially in European countries. Recommendations on alcohol consumption are controversial. On one hand, many nonrandomized studies defend that moderate consumption has a beneficial cardiovascular effect or a lower risk of all-cause mortality. On the other hand, alcohol is associated with an increased risk of cancer, neurological diseases, or injuries, among others. For years, efforts have been made to answer the question regarding the safe amount of alcohol intake, but controversies remain. Observational studies advocate moderate alcohol consumption following a Mediterranean pattern (red wine with meals avoiding binge drinking) as the best option for current drinkers. However, agencies such as the IARC recommend abstention from alcohol as it is a potent carcinogen. In this context, more randomized trial with larger sample size and hard clinical endpoints should be conducted to clarify the available evidence and provide clinicians with support for their clinical practice.

To assess the efficacy of three lifestyle interventions on the reduction of liver fat content and metabolic syndrome (MetS), and whether such reductions would influence renal outcomes, we conducted a randomized controlled trial on 128 participants with MetS and non-alcoholic fatty liver disease (NAFLD), as well as available data on estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatine ratio (UACR). Patients were randomized in 1:1:1 ratio to either Conventional Diet, Mediterranean diet (MD)–high meal frequency, and MD–physical activity groups. Each intervention aimed at reducing caloric intake by 25%–30% of baseline intake and increase energy expenditure by 400 kcal/70 kg. Patients attended regular visits and were followed-up for 6 months. Increased albuminuria was present in 13.3% of patients, while 32.8% showed hyperfiltration. UACR reduction was associated with higher levels of UACR at baseline but not with changes in liver fat. eGFR decreased in patients presenting hyperfiltration at baseline and was associated with reduction in liver fat and insulin resistance, as well as with increase in energy expenditure (R² = 0.248, p = 0.006). No significant differences were observed between the three treatment groups. In patients with NAFLD and MetS, energy expenditure significantly reduced hepatic fat accumulation and insulin resistance, which reduced glomerular hyperfiltration. Increased albuminuria was reduced, but it was not associated with reduced liver fat.

Since the 1950s, when Ancel Keys popularized the traditional Mediterranean diet, an immense accrual of large and valid studies, including prospective cohort studies, randomized controlled trials (RCT), and systematic reviews, have been conducted to investigate the potential health benefits related to this dietary pattern. The available evidence shows that the traditional Mediterranean diet represents a sustainable, healthy, and highly palatable pattern with a wide array of associated health benefits. In particular, its protective effects on cardiovascular disease have been supported by several consistent large RCTs, namely, the Lyon Diet-Heart Study, PREDIMED, PREDIMED-Plus and CORDIOPREV. The traditional Mediterranean diet is not a vegetarian diet, but it emphasizes the preferential consumption of minimally processed plant-based foods: fruits, vegetables, whole-grain cereals, legumes, and tree nuts. Its unique components—different from other healthy, plant-based, food patterns—are extra-virgin olive oil as the main source of fat (keeping a high monounsaturated-to-saturated fat ratio), a high consumption of tree nuts, and low-to-moderate consumption of red wine with meals. However, the inclusion of an alcoholic beverage in a healthy diet is becoming increasingly controversial. An ongoing RCT, the University of Navarra Alumni Trialist Initiative (UNATI), aims to answer this question in 10 000 drinkers. In addition to conventional epidemiologic studies, metabolomics techniques have been applied to assess the role of adherence to the Mediterranean diet and to better understand the mechanisms involved in the protection afforded by this interesting dietary pattern. In this review, we update the available scientific evidence.

The aim of this study was to assess the association between alcohol intake and premature mortality (younger than 65 years) and to explore the effect of potential alcohol underreporting by heavy drinkers. We followed-up 20 272 university graduates. Four categories of alcohol intake were considered (abstainer, light, moderate and heavy consumption). Repeated measurements of alcohol intake and updated information on confounders were used in time-dependent Cox models. Potential underreporting of alcohol intake by some heavy drinkers (likely misclassified as light or moderate drinkers) was explicitly addressed in an attempt to correct potential underreporting by using indirect information. During 12·3 years of median follow-up (interquartile range: 6·8–15·0), 226 participants died before their 65th birthday. A higher risk of early mortality was found for the highest category of alcohol intake (≥50 g/d) in comparison with abstention (multivariable-adjusted hazard ratio (HR) = 2·82, 95 % CI 1·38, 5·79). In analyses of alcohol as a continuous variable, the multivariable-adjusted HR was 1·17 (95 % CI 1·08, 1·26), for each 10 g/d of alcohol. This harmful linear association was present both in uncorrected models and in models corrected for potential underreporting. No significant inverse association between light or moderate alcohol intake and premature mortality was observed, even after correcting for potential misclassification. Alcohol intake exhibited a harmful linear dose–response association with premature mortality (<65 years) in this young and highly educated Mediterranean cohort. Our attempts to correct for potential misclassification did not substantially change these results.