Alcohol consumption and health

The relationship between alcohol consumption and health has been the subject of formal scientific research since at least 1926, when Dr. Raymond Pearl published his book, Alcohol and Longevity, in which he reported his finding that drinking alcohol in moderation was associated with greater longevity than either abstaining or drinking heavily. Since that time


 * “Data have come in from all over the world. Studies have focused on both men and women, various age groups, and people of many ethnic groups. The conclusion remains the same: those who drink moderately live longer and have less risk of developing heart disease than those who abstain from alcohol. Published papers now total in the many hundreds.".


 * To determine if moderate drinkers have fewer heart attacks because they might lead more healthful lifestyles than do abstainers or heavy drinkers, Harvard scientists recently reported their study of only healthy men who led healthful lifestyles. For up to 16 years the doctors monitored the health of 8,867 men who didn't smoke, were of normal weight, exercised at least 30-60 minutes per day, and ate a balanced healthful diet. Among these healthy men with healthy lifestyles, those who consumed anywhere from 1/2 to two alcoholic drinks of beer, wine or liquor per day had significantly decreased risk of heart attacks. Those who averaged slightly more (one to two drinks per day) had the lowest risk. This study strongly suggests that the beneficial effects of drinking alcohol in moderation comes from the alcohol itself rather than from differences in lifestyle Other research also addresses this question.


 * Another study found that when men increased their alcohol intake from very low to moderate, they significantly reduced their risk of coronary heart disease. The study monitored the health of 18,455 males for a period of seven years.


 * Drinking in moderation has also been found to help those who have suffered a heart attack survive it. Alcohol helps reduce damage after heart attacks


 * Much evidence is not simply correlational or time sequence in nature. Some of the many specific ways by which alcohol leads to improved cardiovascular health are now understood, often in great detail.

Such widely different types of evidence based on different methodologies largely rule out the possibility that some factor or factors other than the alcohol itself is causing the significant reductions in fatalities found among moderate drinkers around the world.

While it is widely recognized that alcoholism has negative health effects, moderate consumption, frequently defined as the consumption of 1-4 alcoholic drinks in a day (depending on the age and gender of the subjects) has been found in much research to have a positive effect on longevity (Doll & Peto). See the main article Recommended maximum intake of alcoholic beverages for a list of governments' guidances on alcohol intake which, for a man, range from 140 to 280g per week.

However, research suggests to some that the benefits of moderate alcohol consumption may not be large enough or certain enough to recommend to those who do not already drink, even if not contraindicated. There is a concern that doing so might lead to symptoms of alcoholism in those who previously did not imbibe or that those who drink heavily would interpret the advice as support for heavy drinking. Dr. Tim Naimi and others at the US Centers for Disease Control and Prevention (CDC) speaks widely concerning what they consider the supposed benefits of moderate alcohol intake, pointing out that the research designs that have led to such conclusions are not generally indicative of a cause and effect.

On the other hand, Dr. R. Curtis Ellison, a physician and leading medical researcher, says that adults should have a drink a day, unless contraindicated. “The bottom line is, never go more than 24 hours without a drink” says Dr. Ellison, who is chief of preventive medicine and epidemiology at Boston University School of Medicine. Dr. Ellison recommends that other doctors prescribe a drink a day to their patients to promote better health and greater longevity. (Join Together Online; Health Reformer, January 12, 2004; also see Ellison, R.C. Does Moderate Alcohol Consumption Prolong Life? NY: American Council on Science and Health, 1993; Ellison, R.C. Continuing reluctance to accept emerging scientific data on alcohol and health. AIM Digest, 2002, 11(1), 6-9.) Similarly, well-known medical authority Dean Edell, M.D., asserts that “you would have to be living on another planet not to know that alcohol -- in moderation -- is good for your health.” (Edell, D. Life, Liberty, and the Pursuit of Healthiness. NY: HarperCollins, 2004, p.488)

Background
Research extending back as far as 1926 has demonstrated that drinking in moderation is associated with greater longevity than is either abstaining or abusing alcohol.

One possible explanation is the effect of alcohol on cardiovascular disease, the leading cause of mortality in the United States and many other industrialized countries. This has been studied since 1904.

Physiological effects of ethanol
Alcohol appears to be hormetic. Medical research demonstrates that, consumed in moderation, alcohol increases HDL (“good cholesterol”), decreases thrombosis (blood clotting), reduces fibrinogen (a blood clotter), increases fibrinolysis (clot dissolving), reduces artery spasm from stress, increases coronary blood flow and increases insulin sensitivity -- all good for heart health (Rimm; Zhang).

Alcohol production in the body
It is inevitable that all humans always have some amount of alcohol in their bodies at all times, even if they never drink alcoholic beverages in their lives. This is because of a process called endogenous ethanol production. Many of the bacteria in the intestines use alcohol fermentation as a form of respiration. This metabolic method produces alcohol as a waste product, in the same way that metabolism results in the formation of carbon dioxide and water. Thus, human bodies always contain some quantity of alcohol produced by these benign bacteria.

Mortality
Light and moderate drinking saves more lives in England and Wales than are lost through the abuse of alcohol according to scientists at the University of London. The researchers determined that if everyone abstained from alcohol, death rates would be significantly higher. In the words of the lead author, "alcohol saves more lives than it costs." (Britton, A., and McPherson, K. Mortality in England and Wales attributable to current alcohol consumption. Journal of Epidemiology and Community Health, 2001, 55(6), 383-388. ) Other researchers, led by Dr. Ian White, found that, in the United Kingdom, 15,080 deaths were prevented through the use of alcohol, while 13,216 were caused by its abuse. Thus, the use of alcohol led to a net gain of 1,864 lives. (Dodson, Roger. Alcohol prevents more deaths than it causes. Independent News (UK) May23, 2004)
 * United Kingdom: "In 2004 there were 8,221 alcohol-related deaths in the UK, almost double the total of 4,144 in 1991."

Research by the U.S. Centers for Disease Control and Prevention (CDC) and the National Institute on Alcohol Abuse and Alcoholism (NIAAA) reveals that the benefits of moderate drinking outweigh the harms from abusive drinking. The NIAAA calculates that if all drinkers in the U.S. became abstainers, there would be an additional 80,000 deaths per year. Abstaining dramatically increases the risks of heart attack, ichemic stroke, and many other diseases and life-threatening conditions. The CDC calculates that abusive drinking lead to about 75,766 deaths from all causes in 2001, a number that continues to decline. Therefore, these analyses indicate that moderate alcohol consumption saves more lives than are lost as a result of alcohol abuse. (Gunzerath, Lorraine, et al. National Institute on Alcohol Abuse and Alcoholism Report on Moderate Drinking, Alcoholism: Clinical & Experimental Research, 2004, 28(6), 829-84; Midanik, L.T., et al. alcohol-attributable deaths and years of potential life lost --- United States, 200. Morbidity and Mortality Weekly Report (MMWR), 2004 (September 24), 53(37) (Centers for Disease Control and Prevention).)
 * United States: A 2001 report estimates that medium and high consumption of alcohol led to 75,754 deaths in the USA. Low consumption has some beneficial effects so a net 59,180 deaths were attributed to alcohol.


 * Australia:The Cancer Council of New South Wales concludes that “If the net effect of total alcohol consumption on Australian society is considered, there is a net saving of lives due to the protective effect of low levels of consumption on cardiovascular disease.” (Cancer Council of New South Wales web site)

Overall longevity
Studies support the finding that moderate alcohol consumption is associated with benefits in longevity because of reductions in coronary heart disease, stroke and other diseases such as Alzheimer’s disease, diabetes, duodenal ulcer, hepatitis A, Hodgkin’s lymphoma, non-Hodgkin’s lymphoma, metabolic syndrome, pancreatic cancer, Parkinson's Disease and peripheral arterial disease (PAD)     (Wang & Barker) . Proposed mechanisms of these benefits include the effect of alcohol on cholesterol levels, insulin activity, blood pressure, and the chemistry of blood clotting. Frequently, such studies qualify these findings with admonitions against heavy alcohol consumption or abuse, due to the negative health effects often associated with this behavior.

The U.S. National Institute on Alcohol Abuse and Alcoholism (NIAAA) has completed an extensive review of current scientific knowledge about the health effects of moderate alcohol consumption. It found that the lowest death rate from all causes occurs at the level of one to two drinks per day. That is, moderate drinkers have the greatest longevity.

Research in various countries has found the all-cause mortality rates range from 16 to 28% lower among moderate drinkers than among abstainers   (Yuan).

The medical studies establishing this relationship are large (some include over 200,000 people), cross-cultural (have been conducted in countries around the world), and are sometimes long-term (the longest beginning in 1948 and continuing to this day).

To test the hypothesis that the results may reflect the poor health of alcoholics who now abstain, some studies have restricted the abstainers studied to lifelong teetotalers. Others have controlled for lifestyle factors, income levels, educational levels and other factors. The results have remained the same: moderate drinkers tend to live longer than abstainers or heavy drinkers. Other studies contradict this view.

A 23-year prospective study of 12,000 male British physicians aged 48–78, found that overall mortality was significantly lower in the group consuming an average of 2–3 "units" (British unit = 8g) per day than in the non-alcohol-drinking group (relative risk 0.81, confidence interval 0.76-0.87, P = 0.001). The authors noted that the causes of death that are already known to be augmentable by alcohol accounted for only 5% of the deaths (1% liver disease, 2% cancer of the mouth, pharynx, larynx, or oesophagus, and 2% external causes of death) and were significantly elevated only among men consuming >2 units/day.

In a 1996 American Heart Association scientific statement, Thomas A. Pearson, MD, Ph.D noted, "A large number of observational studies have consistently demonstrated a U-shaped relation between alcohol consumption and total mortality. This relation appears to hold in men and women who are middle aged or older. The lowest mortality occurs in those who consume one or two drinks per day. In teetotalers or occasional drinkers, the rates are higher than in those consuming one or two drinks per day. In persons who consume three or more drinks per day, total mortality climbs rapidly with increasing numbers of drinks per day."

Heart and circulatory diseases
The World Health Organization Technical Committee on Cardiovascular Disease asserted that the relationship between moderate alcohol consumption and reduced death from heart disease could no longer be doubted. Consumption of red wine may be particularly favourable, since red wines contain certain polyphenol antioxidants associated with cardiovascular health.

Pearson reviewed the evidence supporting the effect of alcohol consumption on coronary heart disease (CHD): "More than a dozen prospective studies have demonstrated a consistent, strong, dose-response relation between increasing alcohol consumption and decreasing incidence of CHD. The data are similar in men and women in a number of different geographic and ethnic groups. Consumption of one or two drinks per day is associated with a reduction in risk of approximately 30% to 50%. Studies of coronary narrowings defined by cardiac catheterization or autopsy show a reduction in atherosclerosis in persons who consume moderate amounts of alcohol. In general, the inverse association is independent of potential confounders, such as diet and cigarette smoking. Concerns that the association could be an artifact due to cessation of alcohol consumption in persons who already have CHD have largely been disproved."

Other studies cast doubt on this hypothesis.


 * Angina Pectoris (myocardial infarction). Moderate drinking has been found to reduce the risk of angina pectoris.


 * Peripheral Artery Disease (Peripheral Vascular Disease – PAD). "Moderate alcohol consumption appears to decrease the risk of PAD in apparently healthy men.". "In this large population-based study, moderate alcohol consumption was inversely associated with peripheral arterial disease in women but not in men. Residual confounding by smoking may have influenced the results. Among nonsmokers an inverse association was found between alcohol consumption and peripheral arterial disease in both men and women."


 * Thrombosis (formation of undesirable blood clots anywhere in the body) is lower among moderate drinkers than teetotalers. (Lacoste, L. et al. Acute and delayed antithrombotic effects of alcohol in humans. American Journal of Cardiology, 2001, 87, 82-85; Pahor, M., et al.  Alcohol consumption and risk of deep venous thrombosis and pulmonary embolism in older persons. Journal of the American Geriatric Society, 1996, 44(9), 1030-1037; Ridker, P., et al. Moderate alcohol intake may reduce risk of thrombosis. American Medical Association press release, September 22, 1994; Ridker, P.  The Pathogenesis of Atherosclerosis and Acute Thrombosis . In: Manson, J., et al. (Eds.) Prevention of Myocardial Infarction. NY: Oxford University Press, 1996.)

In heart attack patients who are treated with alcohol, the tissues affected by low blood flow are healthier and stronger than those who receive no alcohol because of alcohol's positive effects on artery walls. Similarly, drinking alcoholic beverages in moderation may help patients recover from coronary stenting. Healing appears to be promoted by the inflammation inhibiting effects of alcohol. (Zairis, M.N., et al. C Reactive protein, moderate alcohol consumption, and long term prognosis after successful coronary stenting: four year results from the GENERATION study. Heart, 2004, 90, 419-424.)

The cardiovascular effects of alcohol are not all beneficial, however; studies show that large-quantity consumption of alcohol can lead to alcoholic cardiomyopathy, commonly known as "holiday heart syndrome." Alcoholic cardiomyopathy presents in a manner clinically identical to idiopathic dilated cardiomyopathy, involving hypertrophy of the musculature of the heart that can lead to a form of cardiac arrythmia. These electrical anomales, represented on an EKG, often vary in nature, but range from nominal changes of the PR, QRS, or QT intervals to paroxsysmal episodes of ventricular tachycardia. The pathophysiology of "holiday heart syndrome" has not been firmly identified, but certain hypotheses cite an increased secretion of epinephrine and norepinephrine, increased sympathetic output, or a rise in the level of plasma free fatty acids as possible mechanisms.

Stroke
Compared to abstaining, drinking in moderation is associated with a reduced risk of stroke, whereas abusing alcohol is associated with an increased risk of stroke.

A study of over 22,000 male physicians aged 40-84 years old over an average of 12 years, concluded, "Light-to-moderate alcohol consumption reduces the overall risk of stroke and the risk of ischemic stroke in men. The benefit is apparent with as little as one drink per week. Greater consumption, up to one drink per day, does not increase the observed benefit."

A meta-analysis of 35 previous studies of the effect of alcohol consumption on stroke risk found that "compared with abstainers, consumption of more than 60 g of alcohol per day (i.e., over four standard drinks -- heavy drinking) was associated with an increased relative risk of total stroke, 1.64 (95% confidence interval [CI], 1.39-1.93); ischemic stroke, 1.69 (95% CI, 1.34-2.15); and hemorrhagic stroke, 2.18 (95% CI, 1.48-3.20), while consumption of less than 12 g/d was associated with a reduced relative risk of total stroke, 0.83 (95%, CI, 0.75-0.91) and ischemic stroke, 0.80 (95% CI, 0.67-0.96), and consumption of 12 to 24 g/d was associated with a reduced relative risk of ischemic stroke, 0.72 (95%, CI, 0.57-0.91). The meta-regression analysis revealed a significant nonlinear relationship between alcohol consumption and total and ischemic stroke and a linear relationship between alcohol consumption and hemorrhagic stroke."

Alcohol and cancer
The U.S. Department of Health & Human Services’ National Toxicology Program listed alcohol as a known carcinogen in 2000. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) reports that  "Although there is no evidence that alcohol itself is a carcinogen, alcohol may act as a cocarcinogen by enhancing the carcinogenic effects of other chemicals. For example, studies indicate that alcohol enhances tobacco's ability to stimulate tumor formation in rats (Garro & Lieber). In humans, the risk for mouth, tracheal, and esophageal cancer is 35 times greater for people who both smoke and drink than for people who neither smoke nor drink (Blot et al.), implying a cocarcinogenic interaction between alcohol and tobacco-related carcinogens (Garro & Lieber)."

"3.6% of all cancer cases worldwide are related to alcohol drinking, resulting in 3.5% of all cancer deaths."

The NIAAA states that "Although epidemiologic studies have found a clear association between alcohol consumption and development of certain types of cancer, study findings are often inconsistent and may vary by country and by type of cancer."

Chronic heavy abuse of alcohol increases risk of certain cancers. "Considerable evidence suggests a connection between heavy alcohol consumption and increased risk for cancer, with an estimated 2 to 4 percent of all cancer cases thought to be caused either directly or indirectly by alcohol (Rothman)" indicates the NIAAA.

Drinking alcohol, especially along with smoking, increases the risk of cancers of the mouth, esophagus, pharynx, larynx and liver, and of breast cancer, according to the National Cancer Institute. Except for breast cancer, these cancers are all rare (NIAAA). Moderate consumption does not significantly increase the risk of the most common cancers, except for breast cancer.

The moderate consumption of alcohol increases the risk of several cancers, might decrease the risk of a few others, and is unrelated to the incidence of many forms of cancer – see Alcohol and cancer for details.

Obesity
Contrary to common belief, drinking alcohol does not necessarily lead to weight gain. Most research studies find no increase in body weight, some find an increase, and some find a small decrease among women who begin consuming alcohol (references for this statement are listed in Alcohol and weight). Some of these studies are very large; one involved nearly 80,000 and another included 140,000 subjects.

A study of 14 male subjects concluded that "In free-living subjects over a 6-week period, the addition of two glasses of red wine to the evening meal does not appear to influence any measured variable which may adversely affect body weight or promote the development of obesity during this time period."

A Mayo clinic study of 8,236 men and women found that people who had one or two alcoholic drinks a day were about half as likely to be obese than teetotalers.

Brain development
Consuming large amounts of alcohol over a period of time can impair normal brain development in both rats and humans. Research is lacking on the possible brain effects of light or moderate alcohol consumption among young humans. "Deficits in retrieval of verbal and nonverbal information and in visuospatial functioning were evident in youths with histories of heavy drinking during early and middle adolescence." "Heavy, chronic drinking appears to produce adverse neural effects that are detectable by functional magnetic resonance imaging." "The data suggest that CIE [chronic-intermittent ethanol] exposure during adolescence has a lasting impact on sensitivity to ethanol-induced motor impairments. This effect might stem from a disruption of normal developmental processes."

Abstinence from chronic heavy alcohol consumption encourages new brain cell development, according to a study.

Diseases of the liver

 * Roughly one in four people who consume more than three drinks per day during a period of 10–15 years will experience some level of alcoholic hepatitis.
 * Alcohol is one cause of cirrhosis.

Gastritis and bacterial contamination
"The link between alcohol use and chronic gastritis (stomach inflammation) is clear, although progression from chronic gastritis to neoplasia is less well understood and probably involves other factors in addition to alcohol."

Drinking strong alcoholic beverages with a meal may offer some protection against bacterial contamination. "The antibacterial activity of red and white wine against enteropathogens may protect against bacterial diarrhoea in a similar way to bismuth salicylate. This protective effect helps explain wine's legendary reputation as a digestive aid." "Limited data indicate that drinking alcoholic beverages along with eating food contaminated with Shigella or Salmonella decreases the risk and/or the severity of illness. … During an oyster-borne outbreak of hepatitis A, we studied the effect of ingestion of alcoholic beverages concomitant with consumption of contaminated oysters. … After controlling for potential confounders, we found a protective effect for beverages that have an alcohol concentration of greater than or equal to 10% (odds ratio = 0.1, 95% confidence interval = 0.02-0.9), but not for beverages with an alcohol concentration of less than 10% (odds ratio = 0.7, 95% confidence interval = 0.2-2.9)."

Alzheimer's disease
Studies have found the risks of Alzheimer's disease to be as much as 75% lower among drinkers than among teetotalers. "Regular consumers of alcohol, including those drinking above and below the USDA recommended limits of 1.0 drinks/day for women and 2.0 drinks/day for men, had a significantly lower risk of AD [Alzheimer's Disease] compared to non-drinkers (crude OR's of 0.67 for consumers within the recommended guidelines and 0.48 for alcohol consumption above). … Alcohol consumption within nationally recommended limits may protect against AD. However, it would be premature to recommend this as a prophylaxis until the protective mechanism is understood and further studies are performed to more precisely define the minimal level and duration of exposure necessary to realize a benefit." In subjects drinking 3 to 4 standard glasses per day (> 250 and up to 500 ml), categorized as moderate drinkers, the odds ratio (OR) was 0.19 for incident dementia and 0.28 for Alzheimer's disease, as compared to the 971 non-drinkers. In the 922 mild drinkers (< 1 to 2 glasses per day), there was a negative association only with AD [Alzheimer's Disease], after adjustment (OR = 0.55). "Advising all elderly people to drink wine regularly for prevention of dementia would be however premature at this stage.".

Pancreatitis
Alcohol consumption is a major cause of pancreatitis, in both its chronic and acute forms.

Cognition
Research finds an association between better cognition or thinking ability and moderate drinking. "After adjustment for age, education, and smoking status, men with CVD/diabetes and low-to-moderate alcohol intake had a significantly lower risk for poor cognitive function (MMSE < or = 25) than abstainers (odds ratios of 0.3 for less than one drink and 0.2 for one to two drinks per day). Alcohol intake was not associated with cognitive decline. … Alcohol may result in an acute beneficial effect on cognitive function among those with CVD/diabetes. However, selection bias and unmeasured confounding should be of concern when evaluating these results." "We report a positive association between moderate alcohol intake among middle-aged men and subsequent cognitive performance in later life. However, it is possible that the health risks associated with drinking outweight any potential benefits for many elderly persons." "These findings suggest that, among women, moderate alcohol consumption may have a beneficial effect on cognitive function." "… although a number of studies have noted a measurable diminution in neuropsychologic parameters in habitual consumers of moderate amounts of ethanol, others have not found such changes. Recent studies have also noted some positive effects of moderate ethanol consumption on cognitive performance in the aging human."

Other diseases

 * Diabetes. Moderate drinkers may have a lower risk of diabetes than non-drinkers. "Alcohol intake increases insulin sensitivity and may partly explain both the J-shaped relationship between the prevalence of diabetes and the amount of alcohol consumption and the decreased mortality for myocardial infarction." "Compared with abstainers men who drank 30.0-49.9 g of alcohol daily had a relative risk of diabetes of 0.61." "Consumption of 30 g/d of alcohol (2 drinks per day) has beneficial effects on insulin and triglyceride concentrations and insulin sensitivity in nondiabetic postmenopausal women." After adjustment for age, randomized treatment assignment, smoking, physical activity, and body mass index, the relative risk estimates of diabetes for those reporting alcohol use of rarely/never were 1.00 (referent), 1 to 3 drinks per month 1.03, 1 drink per week 0.89, 2 to 4 drinks per week 0.74, 5 to 6 drinks per week 0.67, and 1 or more drinks per day 0.57. "The results of this study suggested that moderate alcohol consumption may reduce the risk of type 2 diabetes. On the other hand, binge drinking and high alcohol consumption may increase the risk of type 2 diabetes in women."


 * Essential tremors can be temporarily and dramatically relieved in up to two-thirds of patients by drinking small amounts of alcohol, thus avoiding the serious side effects of the most effective  and expensive medications or the dangers of surgery. (Charles P. D., et al. Classification of tremor and update on treatment. American Family Physician, 1999, 59(6), 565-72;  Bain, P. G., et al. A study of hereditary essential tremor. Brain, 1994, 117(Pt 4), 805-24 ; Lou, J.S., & Jankovic J. Essential tremor: clinical correlates in 350 patients. Neurology,  1991, 41(2 Pt 1), 234-8;  Singer C, et al.  Gait abnormality in essential tremor. Movement  Disorders,  1994, 9(2), 193-6;  Wasielewski PG, et al. Pharmacologic treatment of tremor. Movement  Disorders, 1998, 13(Suppl 3), 90-100; Boecker, H., et al. The effect of ethanol on alcoholic-responsive essential tremors: a positron emission tomography study. Annals of Neurology, 1996, 39, 650-658, 1996; Setting a steady course for benign essential tremor. The Johns Hopkins Medical Letter, 1999 (December), 11(10).)


 * Peptic ulcers. "These results suggest a protective effect of alcohol consumption against active infection with H pylori…". Another study concluded, "Adjusting for other risk factors, alcohol intake (comparing those who drink > 30 gm of alcohol per day to nondrinkers) was not associated with higher risk of duodenal ulcer (RR = 0.74; 95% CI = 0.42-1.29)."


 * Gallstones. Research has found that drinking reduces the risk of developing gallstones. "Compared with alcohol abstainers, the relative risk of gallstone disease, controlling for age, sex, education, smoking, and body mass index, was 0.83 … for occasional and regular moderate drinkers (< 25 ml of ethanol per day), 0.67 … for intermediate drinkers (25-50 ml per day), and 0.58 … for heavy drinkers. This inverse association was consistent across strata of age, sex, and body mass index." Frequency of drinking also appears to be a factor. "An increase in frequency of alcohol consumption also was related to decreased risk. Combining the reports of quantity and frequency of alcohol intake, a consumption pattern that reflected frequent intake (5-7 days/week) of any given amount of alcohol was associated with a decreased risk, as compared with nondrinkers. In contrast, infrequent alcohol intake (1-2 days/week) showed no significant association with risk. … Recommendations regarding the benefit of moderate quantities of alcohol for gallstone disease should be weighed against the potential health hazards of alcohol consumption."


 * Gallbladder disease. Consumption of alcohol is unrelated to gallbladder disease. However one study suggested that drinkers who take Vitamin C (ascorbic acid) might reduce their risk. "After adjustment for potential confounding variables, use of ascorbic acid supplements among drinkers was associated with a decreased prevalence of gallbladder disease … and cholecystectomy …. Use of ascorbic acid supplements among non-drinkers was not significantly associated with either prevalence of gallbladder disease or cholecystectomy. Further study is necessary to confirm our findings and, specifically, to examine the combined effects of ascorbic acid and alcohol on cholesterol metabolism."


 * Kidney stones. Research indicates that drinking alcohol is associated with a lower risk of developing kidney stones. One study concludes, "Beer consumption was inversely associated with risk of kidney stones; each bottle of beer consumed per day was estimated to reduce risk by 40% …. Since beer seemed to be protective against kidney stones, the physiologic effects of other substances besides ethanol, especially those of hops, should also be examined." "…consumption of coffee, alcohol, and vitamin C supplements were negatively associated with stones." "After mutually adjusting for the intake of other beverages, the risk of stone formation decreased by the following amount for each 240-ml (8-oz) serving consumed daily: caffeinated coffee, 10%; decaffeinated coffee, 10%; tea, 14%; beer, 21%; and wine, 39%." "…stone formation decreased by the following amount for each 240-mL (8-oz) serving consumed daily: 10% for caffeinated coffee, 9% for decaffeinated coffee, 8% for tea, and 59% for wine." (CI data excised from last two quotes.).


 * Osteoporosis. Moderate alcohol consumption is associated with higher bone mineral density in postmenopausal women. "…alcohol consumption significantly decreased the likelihood [of osteoporosis]." "Moderate alcohol intake was associated with higher BMD [bone mineral density] in postmenopausal elderly women." "Social drinking is associated with higher bone mineral density in men and women [over 45]."


 * Spontaneous abortion is linked to alcohol consumption.

Health effect and type of alcohol consumed
A study concluded, "Results from observational studies, where alcohol consumption can be linked directly to an individual's risk of coronary heart disease, provide strong evidence that all alcoholic drinks are linked with lower risk. Thus, a substantial portion of the benefit is from alcohol rather than other components of each type of drink."

Dr. Dean Edell writes that there are “differences of opinion about whether beer, wine, or liquor offers the quickest route to a longer life. Of ten major studies, one-third found this true for wine, one-third for beer, and one-third for liquor. Most researchers now believe that it is the alcohol in all of them that provides the magic, but they don’t rule out other components of alcoholic beverages”.

One review suggests that red wine, particularly from areas of cold climate, seems to offer increased cardio-vascular protection and speculates that the effect results from polyphenols, chemical components contained in grape skin.

Recommending alcohol consumption to "teetotalers"
Recommendation to an abstainer to become a moderate drinker is controversial because of the potential health hazards of alcohol abuse.

"Given that there is a vast panoply of very effective and under-used cardiovascular drugs and that the beneficial effects of alcohol are small and ill-understood, all those present at the Novartis Foundation meeting concurred that global recommendations such as '1-3 drinks per day are good for you' are not only meaningless but also irresponsible."

"People who choose not to drink alcohol should not be urged to drink to gain any potential health benefit… Non-drinkers can use other strategies, such as regular exercise, giving up smoking, and a healthy diet, to gain protection against heart disease."

Comparison with health benefits of exercise and diet
Some of the benefits of moderate drinking can be obtained from having a low-fat diet, exercising regularly (for heart health), and eliminating excess salt from the diet. On the other hand, Dr. Eric Rimm of Harvard reports that people have increases of 10 to 30 percent in HDL in a week from drinking alcohol. He says that “nothing else in the diet can have such a dramatic impact on HDL in such a short time”.

Drinking alcohol in moderation can have a greater impact on reducing heart disease than any factor other than the cessation of smoking. And both drinking in moderation and not smoking contribute to the effectiveness of other lifestyle improvements.

Moderate consumption
Moderate consumption of alcohol is defined by the U.S. Department of Agriculture and the Dietary Guidelines for Americans as no more than two drinks for men and one drink for women per day. It is defined by the U.S. National Institute on Alcohol Abuse and Alcoholism (NIAAA) as four drinks per day, not to exceed 14 per week for a man and three per day, not to exceed 14 per week for a woman. The UK equivalent is 3-4 units per day for men and 2-3 units for women. See the main article Recommended maximum intake of alcoholic beverages for a list of governments' guidances on alcohol intake which, for a man, range from 140 to 280g per week.

An exhaustive review of all major heart disease studies has found that "moderate consumers (1 to 2 drinks/day) were at a lower risk of coronary heart disease than nonconsumers or heavy consumers. Evaluation of total mortality in relationship to alcohol consumption reveals that a similar U-shaped relationship to longevity exists." "A substantial portion of the benefit is from alcohol rather than other components of each type of drink." However, studies have also shown that episodic heavy drinking increases the risk of major coronary events such as coronary heart disease and stroke, even in users whose overall volume of drinking was low.

Other possibilities are that moderate drinkers have more healthful lifestyles (making them healthier), higher economic status (giving them greater access to better foods or better healthcare), higher educational levels (causing them to be more aware of disease symptoms), etc. However, when these and other factors are considered, the conclusion again remains the same: moderate drinkers are less likely to suffer cardiovascular disease, which is the leading cause of death in Europe and the Americas. In addition, research has demonstrated specific mechanisms whereby alcohol significantly reduces cardiovascular disease   ,     may reduce the risk of dementia, and even indirectly facilitate memory and learning. However, a study published in the British Medical Journal found that, after adjusting for other potentially confounding factors, alcohol consumption had no noticeable effect on the risk of coronary heart disease. This was true for the full range of the test group, including both non-drinkers and heavy drinkers. The study's authors state that the difference may be explained by the exclusion of people who were of ill health who in other studies may have been included in the non-drinker category, as well as other variables, particularly socioeconomic background.

According to the New England Journal Of Medicine, compared to abstainers, those who drink alcohol regularly have higher death rates from injuries, violence, suicide, poisoning, cirrhosis, certain cancers, and possibly hemorrhagic stroke. Also according to the NEJM, for men under the age of 34 and women under the age of 45, those reporting no alcohol intake have the lowest mortality rate. The British Medical Journal found that the risks of several types of cancer increase for those who consume alcohol in comparison to lifelong abstainers. This was true even for moderate drinkers.

Heavy consumption
Heavy consumption is detrimental to the user's health. People under the influence of alcohol sometimes find themselves in dangerous or compromising situations where they would not be had they remained sober.

Some people are predisposed to developing a chemical dependency to alcohol, alcoholism. The results of alcoholism are considered a major health problem in many nations. The development of alcoholism does not take place in the absence of alcohol, but neither does the presence of alcohol cause it.

Children of alcoholic parents have 4 times more chance to becoming addicted themselves.

Alcohol is said to be a factor in about 50% of deaths in car accidents, 50% of homicides and 25% of suicides. 

The neurological effects of alcohol use are often a factor in deadly motor vehicle accidents. Operating a motor vehicle or heavy machinery under the influence of alcohol is a serious crime in almost all developed nations.

Alcohol compared to other drugs
A 2007 paper in The Lancet attempted to classify drugs by the harm they do; it puts alcohol in fifth place behind heroin, cocaine, barbiturates, and street methadone.