The report on the Alcohol Intake and Health study methodology is relevant to American wine drinkers as it will influence future dietary guidelines and, therefore, public perception and consumption of wine. ICCPUD’s proposed methodology was worrying, given the makeup of anti-alcohol activists and non-U.S. experts, as it would lead to biased guidelines and stringent alcohol limits. The lead author, Timothy S. Naimi, had previously pushed for Extremely Precautionary Guidelines that were rejected in both the U.S. and Canada for insufficient evidence.
Given the fact that this legislation may spark off a chain of events on the wine business and health aspects, we were asked to submit a report on the subject. The National Wine School supplied a detailed white paper to the  U.S. Department of Health and Human Services, questioning the efficacy of proposed methodologies and discussing the benefits of moderate wine consumption. The experience of Wallace and the serious commitment of the school to balanced, rigorous research underlines the demand for guidelines that allow for the subtle health benefits of wine and, indeed, its cardiovascular advantages.
With wine playing such an important economic and cultural role in the United States, it must be certain to have guidelines based upon balanced, scientifically robust research rather than neo-Prohibitionist agendas. Fair representation of a range of scientific opinions in forming realistic dietary guidelines that benefit the American public is paramount and must include those related to the benefits stemming from moderate wine consumption.
The following is a condensed version of the submission.
## Introduction
This paper critically assesses the proposed methodology and protocols outlined by ICCPUD for conducting the Alcohol Intake and Health study. The primary purpose is to establish whether the proposed methodologies are adequate, clear, scientifically sound, and can efficiently reduce biases, while at the same time offering improvements and additional data sources where appropriate.
## Evaluation of Protocol and Methodology
Topic Areas Sufficiency
The proposed topic areas include weekly thresholds, per occasion thresholds, alcohol use among vulnerable populations, and hazardous individual circumstances. Indeed, these are very significant areas in determining the alcohol intake factor and how it combines with other factors to health outcomes. One cannot, however, notice the explicit avoidance of the specific impact of moderate consumption which, in this case, the wine variety has been previously documented to have unlike other alcohol beverages.
### Clarity and Transparency of Methodology
It is a very detailed and rather transparent methodology that includes PRISMA guidelines on the conduct of systematic reviews and meta-analyses, along with evidence assessment done according to the GRADE approach. This lays down a framework for high transparency and reproducibility in the study process.
Methods’ Scientific Validity
In general, the methods that are proposed are scientifically sound and based on well-established protocols for conducting a systematic review with meta-analysis. Nonetheless, assessing alcohol effects by its ethanol content-most especially without regard to types of alcoholic beverages-neglects perhaps such important differences in health outcomes for different types of beverages. Studies have consistently shown, generally, that moderate wine consumption, particularly red wine, might offer protection against cardiovascular diseases in ways that other beverages do not [14,15].
Identification and Minimization of Bias
There is an awareness of the possible bias; namely, there could be confounding variables in the observational studies, and some studies bring in publication bias. Efforts toward the reduction of such bias—through cross-examination using Fleiss’s weighted Kappa for testing inter-rater agreement and the adaptation of robust data extraction protocols—are commendable. However, using lifetime abstainers as a control group has been challenged for being a potential source of bias, since this group may include former drinkers whose health conditions led to abstention from drinking.
##### Alternative Methodological Approaches
This would enhance the robustness of the study in case stratification is done based on types of alcoholic beverages. It may also unravel subtle differences in health effects between different types of alcohol in relation to health outcomes associated with the consumption of alcohol.
Major Limitations and Mitigation Strategies Some major biases are the underreporting of alcohol consumption in population surveys. This could be improved by using biomarkers like phosphatidylethanol rolling paper model (PEth) together with self-reported data in samples, as suggested by Viel et al. (2012). Another limitation includes the longitudinal data that is absent and is required for long-term health effects. A longitudinal cohort would help to decrease this gap.
### Additional Data Sources
Additional inclusion of international studies like the EPIC study (European Prospective Investigation into Cancer and Nutrition) will allow wider inferences and replication of findings from this diverse population.
### Recommended Scientific Papers
1. Rimm, E. B., et al. “Review of moderate alcohol consumption and reduced risk of coronary heart disease: is the effect due to beer, wine, or spirits?” **BMJ**. 1996.
2. Mukamal, K. J., et al., 2003. “Alcohol consumption and risk for coronary heart disease in men with healthy lifestyles.” **Arch Intern Med.**.
3. Shaper, A. G., et al., 1988. “A study of alcohol consumption and coronary heart disease.” **BMJ**. 4. Viel, G., et al., 2012. Phosphatidylethanol in blood as a marker of chronic alcohol use: a systematic review and meta-analysis. **Int J Mol Sci**.
5. Boffetta, P., et al. (2006). Alcohol consumption and risk of cancer: a meta-analysis. **Cancer Causes Control**.
## Conclusion
Although the proposed methods for the Alcohol Intake and Health study were fairly comprehensive and scientifically based, there are some critical areas for improvement. This would involve in-built differentiated analyses for types of beverages with alcohol content, using biomarkers to enhance data accuracy, and accounting for longitudinal data to further enumerated validity and applicability of findings from this study.
Attention to these recommendations by the ICCPUD will go a long way toward more effectively and precisely informative dietary guideline advice by providing nuanced attention to alcohol’s health impacts.
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**Keith Wallace** Senior Researcher, National Wine School **References** Boffetta, P., et al. “Alcohol consumption and risk of cancer: a meta-analysis.” **Cancer Causes Control**. 2006;. – Mukamal, K. J., et al. “Alcohol consumption and risk for coronary heart disease in men with healthy lifestyles.” **Arch Intern Med**. 2003;. – Rimm, E. B., et al. 1996. “Review of moderate alcohol consumption and reduced risk of coronary heart disease: is the effect due to beer, wine, or spirits?” **BMJ**. -Shaper, A. G., et al. 1988. “A study of alcohol consumption and coronary heart disease.” **BMJ**. Viel, G., et al., 2012. “Phosphatidylethanol in blood as a marker of chronic alcohol use: a systematic review and meta-analysis.” **Int J Mol Sci**.
