Alcohol and Metabolic Diseases

Critique 230:  An extensive review of the role of dietary constituents (foods, nutrients, and beverages) in the development of diabetes – 1 August 2019

Reference:  Neuenschwander M, Ballon A, Weber KS, Norat T, Aune D, Schwingshackl L, Schlesinger S.    Role of diet in type 2 diabetes incidence: umbrella review of meta-analyses of prospective observational studies.  BMJ 2019;365:l2368.

Of all lifestyle factors that relate to health and disease, probably the most difficult ones to evaluate are dietary factors, including foods, nutrients, and beverages.  The present paper consists of a meta-analysis (an “umbrella” analysis) based on 53 previous meta-analyses from prospective cohort observational studies.  This analysis includes 153 adjusted summary hazard ratios on dietary behaviors or diet quality indices, food groups and foods, beverages, alcoholic beverages, macronutrients, and micronutrients related to the incidence of type 2 diabetes.  Data from previous meta-analyses on very few foods or nutrients are adequate to clearly determine their effects, but among those that have been identified as reducing the risk of diabetes, high-quality evidence was found only for whole grains, cereal fiber, and alcohol.  As for dietary factors that have strong evidence of increasing the risk of diabetes, the authors of this paper identify only red meat, processed meat, bacon, and sugar-sweetened beverages.

Forum members considered this to be a well-done, appropriate analysis in a paper that summarizes well the current scientific literature.  Some members were concerned about the number of assumptions that scientists must make when doing a simple meta-analysis, and especially when attempting an umbrella one; they consider it key to also evaluate single, large prospective studies where adjustments for many confounding socio-economic factors are less likely to be important.

Overall, the results of this paper strongly support most of the findings of previous meta-analyses and umbrella analyses and indicate only a few dietary factors for which “high-quality” evidence exists for an association with the risk of developing diabetes.  The clearest evidence from the analyses in this paper, which was based only on prospective cohort studies, is that cereal grains and moderate alcohol lower the risk, while meats and sugar-sweetened beverages increase the risk of diabetes.

Given the complexity of evaluating dietary factors for their relation to disease outcomes, it will be useful for future studies to attempt to measure a multitude of foods, beverages, nutrients, and eating patterns, preferably over time, to evaluate further the association with disease.  For now, current evidence suggests that cereals, grains, and moderate alcohol (that decrease risk) and meat and sugar-sweetened beverages (that increase risk) have the most consistent data for a relation to subsequent diabetes mellitus.

For the full critique of this paper by the International Scientific Forum on Alcohol Research, please click here.

Critique 224:  A brief summary of the association between wine/alcohol consumption and health in diabetics   12 March 2019

Diabetes mellitus is an increasingly common condition throughout the world, related closely to increases in obesity and ageing of populations.  There are many, serious health conditions associated with diabetes, especially a marked increase in the risk of morbidity and mortality from cardiovascular disease.  Scientific data from well-done cohort studies have demonstrated for decades that people who are moderate consumers of alcohol tend to have a considerably lower risk of developing diabetes in the first place, and diabetics who consume moderate amounts of alcohol are, in comparison with abstainers, at much lower risk of developing cardiovascular disease.

The present “mini-review” by scientists who have previously carried out the first large randomized clinical trial of wine and health outcomes among diabetics provides an interesting overview of the association of alcohol, particularly of wine, with health.  The authors expand the implications of their research and conclude that “Initiating moderate alcohol consumption among well controlled persons with type 2 diabetes is apparently safe, in regard to changes in heart rate variability and carotid plaque formation.”  Their findings have stimulated this critique by our Forum to also consider if available data now suggest that physicians should encourage the modest consumption of wine with food for selected patients with diabetes.

Our critique describes a number of risk factors (lipid levels, glucose, insulin, etc.) and intermediate conditions (such as endothelial function and arterial calcification) that have been shown to relate to the consumption of alcohol.  Some Forum members believe that while all of these associations are important, the key information needed is the effect of alcohol consumption on disease outcomes themselves (coronary heart disease, stroke, dementia, etc.) and on mortality.  At present, any recommendations regarding alcohol consumption must be based primarily on observational data from long-term cohort studies.

The key question we discuss in this critique is “Should physicians advise their older diabetic patients who are non-drinkers to begin to consume small amounts of an alcoholic beverage?”  The consensus of Forum members is that current data suggest that, at a minimum, we should not advise such patients who currently consume alcohol moderately to stop their consumption. On the other hand, most members emphasize that we should discuss alcohol consumption with all patients.  If they are at least occasional consumers of alcohol (the large majority of patients in most Western countries), our only advice might relate to the pattern of drinking.  At present, the pattern commonly shown to be associated with the lowest risk of the usual diseases of ageing and mortality appears to be small amounts of alcohol, especially wine, with meals on a regular basis.  For patients who indicate that they are drinking only in binges, we should emphasize the adverse health effects (for them as well as for society), and encourage a healthier pattern of drinking.

But what about current non-drinkers?  For middle-aged or older non-drinkers who avoid alcohol because of religious prohibitions, previous misuse of alcohol, certain medical conditions, or a stated dislike of alcohol, our advice on prevention of disease should focus on not smoking, getting exercise, eating a healthy diet, and trying to avoid obesity.  But for patients without such conditions that would indicate that they should avoid alcohol, many Forum members believe that they should at least be told of the current scientific evidence of possible beneficial health effects of regular, moderate intake.  However, until considerably more data on its effects are available, we are not encouraging physicians to prescribe alcohol consumption for their diabetic patients.

Reference:  Golan R, Gepner Y, Shai I.  Wine and Health–New Evidence.  Mini Review.  European Journal of Clinical Nutrition. https://doi.org/10.1038/s41430-018-0309-5; 2019: in press.

For the full critique of this paper by the International Scientific Forum on Alcohol Research, please click here.

Critique 182:  A major meta-analysis on the association of alcohol consumption with the risk of diabetes mellitus —  8 March 2016

Most previous studies have shown that consumers of light-to-moderate amounts of alcoholic beverages tend to have a significant reduction in their subsequent risk of developing Type II diabetes mellitus (DM).  The purpose of the present study was to explore and summarize the evidence on the strength of the association between alcohol consumption and the subsequent risk of DM by using a dose-response meta-analytic approach.  The authors identified 26 prospective cohort studies providing data appropriate for a meta-analysis; their analyses were based on 706,716 individuals (275,711 men and 431,005 women) with 31,621 cases of DM.

This meta-analysis reports that light and moderate drinkers have a significantly reduced risk of developing DM.  For “light” drinkers (defined as an average of ≤ 12 g/day of alcohol), in comparison with non-drinkers, the overall risk ratio for DM was 0.83, with 95% CIs of 0.73, 0.95 (P = 0.005).  For “moderate” drinkers (>12- <24 g/day), the RR was 0.74, with 95% CIs of 0.67, 0.82 (P = 0.001).  Thus, data from this meta-analysis indicate a 17% and 26% reduction in the risk of DM, respectively, for these two drinking categories.

For subjects classified as “heavy” users of alcohol (reported intake averaging ≥ 24 g/day), the RR was 0.98, with 95% CIs of 0.83, 1.09, P = 0.480), interpreted as no effect.  In a figure in the paper showing the separate results for each individual study included, the point estimates for the risk of DM were 1.0 or less than 1.0 for light and moderate drinkers in essentially all studies.  Thus, data from the individual studies support the overall finding of a decrease in risk of DM for light or moderate drinkers.

Sub-group analyses showed that when subjects were stratified by sex, age, BMI, smoking, physical activity, and family history of DM, the point estimates of the risk ratios associated with light or moderate alcohol consumption were less than 1.0 in all groups, adding further to the robustness of the overall conclusions of a reduction in risk of DM from alcohol intake.  Similarly, for all subjects, as well as for men and women separately, there was a clear U-shaped curve for the association.  The nadir of the effect was just over 20 grams of alcohol per day (about 2 typical drinks), and even the risk of heavy drinkers did not reach the estimated risk of non-drinkers.

Forum members considered this to be a well-done analysis that confirms most previous results from prospective studies indicating a reduction in the risk of developing DM associated with moderate drinking.  Further, an increasing number of randomized clinical trials are supporting such beneficial effects on the development and clinical treatment of DM.   The Forum thought it unfortunate that beverage-specific results were not available in this study, as increasingly it is being shown that, beyond alcohol effects, there are polyphenols and other substances in wine and beer that provide additional protection against diabetes.  Further, the Forum felt it important to also emphasize the protective effects against cardiovascular disease among subjects who already have DM, who are especially vulnerable to coronary heart disease and other effects of atherosclerosis.

Overall, this meta-analysis based on a large number of subjects indicates that the risk of DM is considerable lower among light and moderate drinkers than among abstainers.  This finding supports the contention that, for most middle-aged and older adults (with the exception of individuals with specific prohibitions against alcohol such as former drug or alcohol abuse, certain types of neurological or severe hepatic disease, etc.), moderate alcohol consumption should be considered as a component of a “healthy lifestyle” that reduces the risk of diabetes and most of the chronic diseases of ageing.

Reference:  Li X-H, Yu F-F, Zhou Y-H, He J.  Association between alcohol consumption and the risk of incident type 2 diabetes: a systematic review and dose-response meta-analysis.  Pre-publication: Am J Clin Nutr 2016; doi: 10.3945/ajcn.115.114389.

For the full critique of this paper by members of the International Scientific Forum on Alcohol Research, please click here.

Critique 174:  Two-year clinical trial of wine administration in diabetics who were previous abstainers or very-light drinkers  —  19 October 2015

Observational epidemiologic studies have consistently found that moderate drinkers are at lower risk of cardiovascular disease (CVD); such alcohol consumption also lowers both the risk of diabetes as well as of CVD among diabetics.  However, there have been few clinical trials of the administration of alcohol or wine among diabetics, and most have been for relatively short periods of time.  Forum members welcomed the publication of the results of the present study, and consider that it provides valuable information on the relation between wine and cardiometabolic risk.

In this study, among 224 subjects with diabetes aged 40 to 75 years who were abstainers or very light drinkers (previously reported none or < 1 drink/week), the investigators carried out a randomized clinical trial of the effects of wine on cardiometabolic factors.  The subjects were randomly assigned to 150 mL of mineral water, white wine, or red wine with dinner for 2 years; all groups followed a Mediterranean diet without caloric restriction.  The study was described to subjects as a dietary intervention, and there were group sessions led by clinical dietitians each month for the first three months and then at 3-monthly intervals thereafter.  The focus was on the Mediterranean diet, and wine was not discussed at these meetings.  There was excellent compliance with the provided beverages (>80%) and excellent continued participation of subjects (94% for one year and 87% for the full two years).

The key results of this study were that the administration of 150 ml of red wine with dinner each evening, in comparison with mineral water, favorably affected many cardiometabolic factors, and especially led to an increase in HDL-cholesterol and apolipoprotein (a).  The administration of similar amounts of white wine was also beneficial, and specifically improved measures of glycemic control.

Further, in 203 of the subjects, effects according to the genetic factors determining ADH were evaluated.  In the study, 35.6% of subjects were homozygous for the polymorphism for “slow ethanol metabolism,” 21.3% were homozygous for that for “fast ethanol metabolism,” and 43% were heterozygous.  Forum members agreed with the summary statement of the authors: “We found that diabetic patients who were slow alcohol metabolizers had improved glycemic control by initiating moderate wine consumption, which suggests that alcohol may play a role in glucose metabolism.  In contrast, diabetic patients who were fast ethanol metabolizers benefited the most from the wine-induced BP-lowering effect, which suggests a mediatory role for ethanol metabolites.”

The study has important implications for advice to be given to diabetics.  Most, but not all, Forum members agreed with the authors’ conclusion that “Initiating moderate wine intake, especially red wine, among well-controlled diabetics as part of a healthy diet is apparently safe and modestly decreases cardiometabolic risk.”

Reference:  Gepner Y, Golan R, Harman-Boehm I,  . . .  Stampfer MJ, Shai I, et al.  Effects of initiating moderate alcohol intake on cardiometabolic risk in adults with type 2 diabetes.  A 2-year randomized, controlled trial.  Ann Intern Med 2015; pre-publication.  doi:10.7326/M14-1650

For the full critique of this paper by members of the International Scientific Forum on Alcohol Research, please click here. 

Critique 172:  Alcohol and the risk of developing diabetes  —  7 October 2015

Prospective cohort studies for decades have tended to show that the risk of developing Type II diabetes mellitus is reduced among moderate drinkers in comparison with non-drinkers, with previous meta-analyses suggesting that moderate drinkers may have about 30% lower risk than that of abstainers. The present study carried out a multi-language search for studies on alcohol and diabetes and conducted a meta-analysis involving almost two million subjects from a final group of 38 cohort, case-cohort, case-control, or nested case-control studies.  The main conclusions of the authors are that only females may show a significant inverse association between alcohol consumption and the risk of diabetes, and that previous studies may have overestimated the reduction in risk from moderate drinking.

Forum members had concerns about the analyses and the conclusions of the authors, as the males in the study were primarily Asian (86%), and there were huge differences between the associations with alcohol for Asian and non-Asian populations.  There are always problems when the basic study data have a marked degree of heterogeneity.  In general, many of the factors that relate to diabetes (diet, body size and adiposity, type of beverages consumed, etc.) are quite different between Asians and non-Asians; combining such groups when their analyses show opposite effects of alcohol on diabetes risk may not be a reasonable way of trying to develop results that apply globally.  Forum members do not believe that the analyses presented in this paper can support the conclusion of the authors that there is “no effect among males.”  It could be unwise if the results of this study were used to develop alcohol guidelines for western populations.

The authors could not take the pattern of drinking (regular versus binge) or the type of alcohol into consideration.  Clinical trials have suggested that wine and its polyphenols may have effects above and beyond those seen with alcohol alone, and beneficial effects of such polyphenols have been demonstrated both for women and for men.  Thus, while the analyses in this paper were all carried out accurately, attempting to use these data to develop guidelines that would apply globally, as was done by the authors, may not be appropriate.

Reference:  Knott C, Bell S, Britton A.  Alcohol Consumption and the Risk of Type 2 Diabetes: A Systematic Review and Dose-Response Meta-analysis of More Than 1.9 Million Individuals From 38 Observational Studies. Diabetes Care 2015;38:1804–1812 | DOI: 10.2337/dc15-0710

For the full critique of this paper by members of the International Scientific Forum on Alcohol Research, please click here.

Critique 159:  Alcohol as a component of the Mediterranean-type diet; effects on the risk of mortality among diabetics  —  17 March 2015

Reference:  Bonaccio M, Di Castelnuovo A, Costanzo S, Persichillo M, De Curtis A, Donati MB, de Gaetano G, Iacoviello L, on behalf of the MOLI-SANI Study Investigators. Adherence to the traditional Mediterranean diet and mortality in subjects with diabetes. Prospective results from the MOLI-SANI study.  European Journal of Preventive Cardiology 2015.  Pre-publication.  DOI: 10.1177/2047487315569409.

Many scientists have reported on health benefits associated with the traditional diet of much of the Mediterranean area: the primary basis of the diet is on plant-based foods (whole grains, vegetables, fruits), olive oil, moderate wine consumption, and limited intake of meat or dairy products.  In 2003, Antonia Trichopoulou and her associates created a scoring system based on the number of components of the Mediterranean Diet (Med-Diet) consumed by subjects, giving a total score to judge the degree that individuals were following a Med-Diet pattern.  The score is based on the intake of 7 items (cereal intake, ratio of monounsaturated to saturated fats, vegetables, fruits, nuts, fish, and moderate alcohol), considered to have positive effects, and 2 items (dairy products, meat and meat products) considered to have negative effects.  Many groups have found that greater adherence to such a diet (a higher score) is associated with a lower risk of many diseases, and lower mortality.  There are limited data on the relative merits of each component of the Med-Diet.  In the present paper, the authors attempt to judge the proportion of the protection against mortality that can be attributed to each component of the score.

The authors’ calculations estimated that, in descending order of importance, moderate alcohol consumption (associated with a reduction of 14.7% in the protection against mortality when it was removed from the total score), cereal intake (12.2% reduction), ratio of monounsaturated to saturated fats (5.8%), and consumption of vegetables (5.8%), fruits and nuts (5.2%) and fish (5.0%) lowered mortality risk.  Lower intakes of dairy products (reduction of 13.4%) and meat and meat products (3.4%) were also associated with lower mortality.  Alcohol has long been known to relate to a lower risk of developing diabetes, and the present study indicates that it is an important factor in reducing the risk of mortality among subjects who have already developed diabetes, as has been shown in previous studies. This study indicates further that the full Med-Diet has very favorable effects on mortality among diabetics.

Forum members considered this to be a well-done attempt to tease apart the relative importance of each component of the Med-Diet as it relates to health outcomes among diabetics.  They felt that these researchers from the MOLI-SANI study have published a convincing paper extending the known benefits of the Mediterranean diet to a cohort of type 2 diabetics, a group of subjects at high risk for cardiovascular and all-cause mortality.

There were some questions raised about the precision of the Med-Diet Score, as published and used in this study, in judging the relative contributions of the different dietary constituents, especially because of known complexities in judging the effects of avoiding one particular food when its absence may affect the intake of other foods.  And for alcohol, the score used did not permit an evaluation of the role of the pattern of drinking or even the type of beverage consumed, which are known to affect the net effects of drinking on health.

Nevertheless, the results of this study add to an accumulating base of knowledge of the importance of the Mediterranean-type diet in reducing the risk of many health outcomes, including mortality among diabetics.

For the full critique of this paper by members of the International Scientific Forum on Alcohol Research, please click here.

Critique 153:  Moderate alcohol intake may lower the risk of developing diabetes among obese subjects  —  11 December 2014

This case-control study compared the risk of having a high level of hemoglobin A1c, a measure of hyperglycemia, and of the waist/height ratio, a measure of obesity, according to reported alcohol consumption.  Overall, subjects reporting an average alcohol intake between 22 and 44 g/day (the equivalent of between about 2 and 4 typical drinks) had lower levels of hemoglobin A1c and lower weight/height values.  The author concludes: “The associations between obesity and hyperglycemia were weaker in light-to-moderate drinkers than in nondrinkers.  Thus, light-to-moderate drinking may reduce the impact of obesity on the risk for diabetes.”

While Forum reviewers had some concerns about the first analytic approach given in the paper, they agreed that the second approach, in which specific levels of A1c were reported according to alcohol intake and measures of obesity, had merit.  These latter data clearly indicate that hyperglycemia is affected both by obesity (which increases the risk) and alcohol intake (which decreases the risk); hyperglycemia is the leading factor associated with the development of diabetes mellitus.

A therapeutic implication of this study may be that obese subjects who are moderate drinkers should not be advised to stop their alcohol consumption.  The results, along with a large amount of other research currently available, also suggest that obese subjects who do not drink and have no contraindications to alcohol consumption should be informed that consuming moderate amounts of alcohol may be associated with a reduction in their risk of developing diabetes.

Reference:  Wakabayashi U.  Light-to-Moderate Alcohol Drinking Reduces the Impact of Obesity on the Risk of Diabetes Mellitus.  J Stud Alcohol Drugs 2014;75:1032–1038.

For the full critique of this paper by members of the International Scientific Forum on Alcohol Research, please click here.

Critique 136:  Alcohol’s effects on cardiovascular risk among subjects with diabetes mellitus  —  18 March 2014

Reference:  Blomster JI, Zoungas S, Chalmers J, Li Q, Chow CK, Woodward M, Mancia G, Poulter N, Williams B, Harrap S, Neal B, Patel A, Hillis GS.  The relationship between alcohol consumption and vascular complications and mortality in individuals with type 2 diabetes mellitus.  Diabetes Care 2014; pre-publication: DOI: 10.2337/dc13-2727

A U- or J-shaped curve for the relation of alcohol consumption to cardiovascular disease (CVD) among diabetics has been shown in most prospective epidemiologic studies for many years, and CVD is the leading cause of death among diabetics.  A variety of potential mechanisms of protection against CVD have been described, including beneficial effects of moderate drinking on lipids, inflammatory markers, and insulin resistance.   The current paper assesses the effects of alcohol use among participants in the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified-Release Controlled Evaluation (ADVANCE) trial.  It was based on more than 11,000 subjects with diabetes from 20 countries, including those in Eastern Europe, Asia, and established market economies in Western Europe, North America, and the Pacific region.  The outcomes over 5 years of follow up were CVD events (death from CVD, non-fatal myocardial infarction, non-fatal stroke), microvascular disease (renal disease, diabetic eye disease), and all-cause mortality.

Key results of the analyses showed that during follow up, more than 1,000 subjects (about 10%) had a major CVD, with similar percentages experiencing a microvascular complication or dying.   The authors report that “Compared with abstainers, any alcohol use was associated with a 17% lower risk of cardiovascular events, a 15% lower risk of microvascular complications, and a 13% lower risk of all-cause mortality.”  While there were few heavy drinkers (<4% of subjects), their data indicated that there was no significant lowering of risk of the outcomes among such subjects.  Subjects who consumed wine had lower estimates of cardiovascular disease outcomes and mortality than consumers of other beverages.

Forum reviewers considered this to be a well-done analysis based on a large cohort of subjects with diabetes mellitus, with an adequate number of non-drinkers to serve as a referent group.  The results strongly support previous studies that have shown a lower risk of cardiovascular events and total mortality among diabetic subjects who consume moderate alcohol.  The study also showed that the risks of microvascular complications (diabetic kidney disease, diabetic eye disease) were lower among moderate drinkers.

The Forum considers this to be an important message (to physicians and the public), as the vascular ravages of diabetes are very serious, and diabetes is such a common disease that is increasing throughout the world.  Diabetic patients without contraindications to alcohol sorely need to know of the potential cardiovascular protection of moderate alcohol consumption.      

For the full critique of this paper by members of the International Scientific Forum on Alcohol Research, please click here

Critique 104:  Moderate alcohol consumption is associated with a lower risk of diabetes   —   26 February 2013

A population-based longitudinal study in Norway showed a lower risk of developing type II diabetes, and a tendency for less auto-immune diabetes, among subjects reporting moderate alcohol consumption.  The lowest risk was among subjects reporting that they consumed alcohol 5-10 times during the previous two weeks or reporting a daily consumption of 10-15 grams of alcohol per day (slightly less than one to a little over one drink per day, using 12 g of alcohol per day as a “typical drink”).

The overall results from this study support most previous research showing a rather large (approximately 30% or more) reduction in the risk of Type II diabetes mellitus to be associated with moderate drinking.  In this study, the strongest protective effect related to the consumption of wine, rather than beer or spirits.  Unlike some previous research, the present study did not show an increased risk of diabetes among binge drinkers, heavier drinkers, those reporting episodes of intoxication, or those giving positive responses on a CAGE questionnaire (a measure of an alcohol use disorder).  As it is likely that alcoholics were under-represented in the cohort, the ability to show the effects of very heavy drinking may have been limited.

While the numbers of subjects with auto-immune diabetes were small, there was a tendency seen for a similar reduction in risk with moderate drinking as with the much more common Type II diabetes.  Overall, this study strongly supports much previous research showing that moderate alcohol consumption is associated with a lower risk of developing diabetes.

Reference:  Rasouli B, Ahlbom A, Andersson T, Grill V, Midthjell K, Olsson L, Carlsson S.  Alcohol consumption is associated with reduced risk of Type 2 diabetes and autoimmune diabetes in adults: results from the Nord-Trøndelag health study.  Diabet Med 2013;30:56–64.

For the full critique of this paper by members of the International Scientific Forum on Alcohol Research, please click here.

Critique 024.  Moderate alcohol consumption lowers risk of metabolic diseases in a population with high mean alcohol intake. 28 November 2010

Reference:  Clerc O, Nanchen D, Cornuz J, Marques-Vidal P, Gmel G, Daeppen J-B, Paccaud F, Mooser V, Waeber G, Vollenweider P, Rodondi N.  Alcohol drinking, the metabolic syndrome and diabetes in a population with high mean alcohol consumption.  Diabet Med 2010;27:1241–1249.

A cross-sectional analysis of data from subjects in Switzerland related varying levels of alcohol intake to the presence of diabetes mellitus, the “metabolic syndrome,” and an index of insulin resistance (HOMA-IR).  The strengths of this paper include being population-based and having a large number of subjects who reported that they consumed 14 or more drinks/week.  Also, there was a good percentage (27%) of subjects reporting no alcohol intake during the one week of assessment used for classifying subjects.  Another strength is the careful confirmation of drinking status with state-of-the-art laboratory tests.  In multivariate analysis, the prevalence of the metabolic syndrome, diabetes and mean HOMA-IR decreased with low-risk drinking and increased with high-risk drinking.  No differences were noted according to the type of beverage consumed.

This is a cross-sectional analysis, so a causative relation between alcohol intake and the metabolic outcomes cannot be assessed.  Still, the data support much that has been shown in prospective studies.  Several Forum members commented on potential problems when considering a number of physiologic conditions as the “metabolic syndrome” and focusing therapy on the syndrome; they believed that each metabolic factor should be evaluated and treated singly.

For the detailed critique of this study by the International Scientific Forum on Alcohol Research, please click here.

Critique 019. Both alcohol and caffeinated coffee intake are associated with lower risk of diabetes in African-American women. 27 September 2010

Reference:  Boggs DA, Rosenberg L, Ruiz-Narvaez EA, Palmer JR.  Coffee, tea, and alcohol intake in relation to risk of type 2 diabetes in African American women.  Am J Clin Nutr 2010;92:960–966.

In a very large cohort of African-American women in the US, the association between the consumption of alcohol, tea, and coffee was related to the development of type 2 diabetes mellitus over a follow-up period averaging 12 years.  Tea and decaffeinated coffee showed no relation with diabetes, but the intake of both caffeinated coffee and alcohol showed a significant inverse association.

This paper is particularly important because some previous studies have not shown a strong association between alcohol and the risk of cardiovascular disease among African-Americans.  African-Americans, especially women, tend to drink little alcohol, yet are at markedly increased risk of diabetes.  In the present study, the approximately 30% lower risk for moderate alcohol drinkers was about the same in these African-American women as has been found in many previous studies of whites.

For the detailed critique of this paper by the International Scientific Forum on Alcohol Research, please click here.

Critique 003. Moderate alcohol consumption markedly reduces the risk of diabetes mellitus, even among subjects with otherwise very healthy lifestyles 17 May 2010

Reference:  Joosten MM, Grobbee DE, van der A DL, Verschuren WWM, Hendriks HFJ, Beulens JWJ.  Combined effect of alcohol consumption and lifestyle behaviors on risk of type 2 diabetes.  Am J Clin Nutr 2010;91: 1777-1783.

In a very well-done analysis from a large Dutch population, it was shown that moderate drinking considerably lowers the risk of developing type 2 diabetes even among subjects who are otherwise following a healthy lifestyle (not obese, non-smokers, physically active, eating a healthy diet).  Thus, it indicates that the effect of moderate drinking on lowering the risk of diabetes cannot be explained by other healthy lifestyle habits of such drinkers.  Moderate drinking should be considered as a complement, and not as an alternative, to other healthy lifestyle habits that lower the risk of chronic diseases such as diabetes and coronary heart disease.

For the full critique of this paper by the International Scientific Forum on Alcohol Research, please click here: