20 Nov Moderate Alcohol Ingestion May Not Benefit Everyone
MedicalResearch.com Interview with:
Department of Public Health and Community Medicine,
Sahlgrenska Academy, University of Gothenburg,
Medical Research: What is the background for this study?
Dr. Mehlig: Many studies found that the ‘good’ HDL-cholesterol is associated with lower risk for atherosclerosis, and cardiovascular risk. This finding has not been translated into clinical practice because medical trials with HDL-cholesterol rising medication did rise the HDL-cholesterol but did not prevent CVD. One possible explanation could be that a high level of HDL-cholesterol is but a marker for other factors that truly contribute to reduced cardiovascular risk. One such factor is alcohol consumption, and ethanol intake in grams / day is associated with higher HDL-C in our study, too. Another factor is a certain genotype that has been found to modulate HDL-cholesterol levels. The fact that co-called ‘moderate’ alcohol consumption is beneficial wrt. CVD has been observed and discussed often, and is confirmed in our study. Here, we asked whether the beneficial effect of alcohol was further strengthened by having a favorable CETP genotype wrt. HDL-cholesterol.
Medical Research: What are the main findings?
Dr. Mehlig: The main finding is that participants with intermediate ethanol intake had a reduced risk of CVD, but that this was observed only in subjects with a certain CETP genotype. We do not know at present why the effect of ethanol appears to differ between CETP genotypes, but we could show that this was not due to differences in HDL-cholesterol.
Medical Research: What should clinicians and patients take away from your report?
Dr. Mehlig: The main message is perhaps a warning that the results should not be translated into medical advice, like to increase alcohol consumption, firstly because these results are derived from an observational study with insufficient evidence for clinical practice, secondly because the protective effect of alcohol might be restricted to a subsample of about 20% of the population with a favorable genotype, but this genotype is usually unknown. The common advice to-day is that women should not exceed 1-2 units per day (or 9 a week), whereas men because of body size can take some more. Binge drinking is not associated with any health benefits at all and should be discouraged.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Mehlig: The present study is purely observational, and meant to contribute to the theoretical understanding of the underlying processes. The self-reported amount usual of alcohol consumption cannot be used as the basis for recommendations, and it cannot be excluded that coronary patients reported a changed consumption after the coronary event. For this reason, we are now following healthy cohort participants over time, with the aim to link genotype and alcohol consumption at the start of the study to the probability of subsequent coronary heart disease. Though still not an experimental study, the prospective study design creates a higher level of evidence for causal associations. Future research should also take into account the type of alcohol consumed, to clarify the role of ingredients such as anti-oxidants that differ by type of alcohol.