Introduction
Over the last 10,000 years, humans have debated about the merits and detriments of fermented drinks. Even today, the debate continues to simmer with lively back and forths over whether alcohol is bad or good for you.
Alcohol is both a tonic as well as a poison. It’s mainly the dosage that makes a difference. Moderate drinking is good for your heart and circulatory system and may protect you from type 2 diabetes and gallstones. In most countries, heavy drinking is the leading cause of preventable deaths. Alcohol is involved in approximately half of all fatal traffic accidents in the United States. [1] Heavy alcohol consumption can harm the liver, heart, and unborn child and increase the risk of breast cancer and other types. It also contributes to depression, violence and relationships.
Alcohol’s dual nature is not a shock. Alcoholic beverages contain a simple molecule known as ethanol that affects the human body in multiple ways. It has a direct effect on the stomach, liver, heart, brain and gallbladder. It influences the levels of insulin and lipids in the blood (cholesterol, triglycerides), as well as inflammation. Also, it affects mood, coordination, and concentration.
What is Moderate Alcohol Consumption? What is a drink?
The ongoing debate over alcohol’s health impact has been fueled by the loose use of terms like “moderate” or “a drink”.
In some studies, the term “moderate consumption” is used to refer to drinking less than one drink per day. However, in other studies, it can mean 3-4 drinks per day. What exactly a “drink” is can also be fluid. Even among alcohol researchers, there is no standard drink definition. [2]
In the U.S., one drink is considered 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of spirits (hard liquors such as gin and whiskey). [3] Each contains 12 to 14 grams on average. However, microbrews or wine with higher alcohol levels are now available.
Is Red Wine better?
Other research indicates that the choice of beverage has little impact on cardiovascular benefits.
It is a balancing act to define moderate drinking. The point of moderate drinking is where the benefits of alcohol outweigh its risks.
This point is based on the latest consensus, which states that men should not drink more than two drinks per day and women should only consume one. The U.S. Department of Agriculture uses this definition in its Dietary Guidelines for Americans, 2020-2025 [3], which is widely accepted throughout the United States.
The Dark Side of Alcohol
Some people drink more than one. Some people don’t drink moderately, while others do.
The body can be affected by excessive drinking. It can lead to liver scarring (cirrhosis), which is a potentially deadly disease. It can cause high blood pressure (cardiomyopathy) and damage the heart muscle. Alcohol consumption is also linked to several types of cancer: the World Cancer Research Fund, American Institute for Cancer Research, and World Cancer Research Fund indicate that there is convincing evidence linking alcohol with cancers in the mouth, pharynx and larynx as well as breast, liver and colon. The International Agency for Research on Cancer found that alcohol-containing ethanol and acetaldehyde (a chemical produced by the breakdown of alcohol) are both carcinogenic in large amounts. [5] Drinkers who smoke or have poor diets are at increased risk.
Families, friends and communities are also affected by problem drinking. According to the National Institute on Alcohol Abuse and Alcoholism and others:
- In 2014, approximately 61 million Americans fell into the category of binge drinkers (5 or more drinks in the same situation at least once per month), and 16 million as heavy drinkers (5 or more drinks in the same problem on five or more days within a single month). [6]
- One in three violent crimes is influenced by alcohol. [7]
- Alcohol was a factor in more than 10,000 automobile accidents that resulted in fatalities in 2015. [8]
- About $249 billion is spent on alcohol abuse each year. [9]
Even moderate drinking carries some risks. Alcohol can interfere with sleep and the ability to make good decisions. Alcohol can interact in potentially harmful ways with many medications, including acetaminophen and antidepressants. Alcohol is addictive, particularly for those with a history of alcoholism.
Alcohol increases the risk of breast cancer.
Alcohol consumption is associated with an increased risk of breast cancer. The more alcohol you drink, the higher the risk. [10-14]
- In a large prospective study that followed 88,084 men and 47,881 women for 30 years, it was found that drinking even one drink per day increased the risk for alcohol-related cancers in women (colorectums, female breasts, oral cavities, pharynxes, larynxes, livers, and oesophagus), but mostly breast cancer. This was true of both nonsmokers and smokers. Men who do not smoke were not at increased risk for alcohol-related cancers if they drank 1 to 2 drinks per day. [15]
- Researchers found that drinking 2-5 drinks per day, compared to not drinking at all, increased breast cancer risk by as much as 41%. The type of alcohol did not matter, whether it was beer, wine or hard liquor. [10] It doesn’t necessarily mean that women who drink 2-5 drinks per day are at risk of breast cancer. It is not the difference between 13 out of 100 women getting breast cancer in their lifetime (the average risk for the U.S.) and 17 to 18 out of 100 women. This modest increase could result in a significant increase in the number of women diagnosed with breast cancer every year.
Breast cancer risk is increased in women who do not consume enough folate or take folic acid as a supplement. Folate is required to create new cells and prevent DNA changes. Folate deficiency can lead to gene changes that can lead to cancer and can be caused by heavy alcohol consumption. Alcohol can also increase estrogen levels, which are responsible for the growth of some breast cancer cells. This increased risk can be reduced by consuming 400 micrograms of folate per day when drinking at least one drink of alcohol each day. [16, 17]
- Researchers found that three factors — genetics, folate consumption, and alcohol — were strongly associated in a cohort of 2866 young women, with an average age of 36, who had been diagnosed with invasive cancer of the breast. The risk of developing breast cancer for those with a history of the disease who consumed 10 grams of alcohol daily (equivalent to 1 or more drinks) and consumed less than 400 micrograms of folate per day was almost two times higher (1.8). Women who consumed this amount of alcohol but had no family history of breast carcinoma and ate 400 micrograms or more of folate per day did not increase their breast cancer risk. [14]
Alcohol and Folate
Alcohol and weight gain
Alcohol contains between 100 and 150 calories per serving. This means that even three drinks a week can add up to 300+ calories. Mixing drinks with juice, syrups, or tonic will increase the calories and risk of weight gain.
A prospective study that followed almost 15,000 men over four years found that higher alcohol intakes were only associated with a minor increase in weight gain. [19] In comparison to those who didn’t change their alcohol consumption, those who increased it by two or more drinks per day gained slightly more than half a pound. The researchers found that alcohol consumption was associated with an increase in calorie intake.
Alcohol and Health
What health benefits can moderate alcohol consumption bring?
Cardiovascular Disease
Over 100 prospective studies have shown an inverse relationship between moderate to light drinking and the risk of heart attacks, strokes caused by clots, peripheral vascular diseases, sudden cardiac deaths, and death due to all cardiovascular causes. [20] This effect is consistent and equates to a reduction of 25-40% in risk. Alcohol consumption above four drinks per day increases the risk of hypertension and abnormal heart rhythms. It can also increase the risk of stroke, heart attack, death, and heart attacks. [5, 21-23]
Alcohol and Heart Disease – Prospective Studies
Men and women have both been shown to be at lower risk for cardiovascular disease when drinking moderately. This applies to both people without heart disease and those who are at high risk of having a stroke, heart attack, or death from cardiovascular disease. Benefits are also extended to older people. [36]
It is a biological and scientific fact that moderate alcohol consumption can protect against cardiovascular disease. Moderate alcohol consumption increases levels of HDL (or “good” cholesterol) [37]; higher HDL levels have been linked to greater protection against cardiovascular disease. Moderate alcohol consumption is also associated with positive changes, from improved insulin sensitivity to factors that affect blood clotting, such as tissue type-plasminogen activater, fibrinogen and clotting factor VII. These changes could help prevent small blood clots from forming in the arteries of the brain, neck and heart. This is the cause of most heart attacks.
The Drinking Patterns of People Matter
It doesn’t matter what you drink, whether it is wine or beer. What matters is how you drink. It’s not the same as drinking one drink per day if you have seven drinks one Saturday and then don’t drink the rest of the weekend. Although the weekly total is the same, the health effects are not. Participants in the Health Professionals Follow-up Study found that drinking alcohol at least three to four times a week was associated with a lower risk of myocardial ischemia. It didn’t matter if you consumed less than 10 grams of alcohol per day or more. What did seem to be important was the frequency with which you consumed it. [25] Danish men showed a similar pattern. [38]
The Nurses’ Health Study I & II reviewed the alcohol consumption of women and found that women who consumed less alcohol (about one drink per day), spread over more than four days, had lower death rates. This was compared to women who consumed the same amount in just one or two days. [39]
A large-scale trial would be the most conclusive way to determine whether alcohol affects cardiovascular disease. Some volunteers could be randomly assigned to drink one or more alcoholic beverages a day. In contrast, others were given drinks that tasted and smelled just like alcohol but contained no alcohol. These trials are usually conducted over weeks or months, sometimes even two years. They aim to measure changes in blood, but no long-term study has been carried out to examine the effects of alcohol. The National Institutes of Health funded a successful U.S. effort to launch an international research study. The NIH stopped the trial despite the fact that the proposal had been peer-reviewed, and the initial participants were randomized either to drink moderately or abstain. A future trial of alcohol on clinical outcomes is unlikely to be conducted again. However, the link between moderate drinking, cardiovascular disease, and all the evidence available today almost certainly shows a cause-and-effect relationship.
Beyond the Heart
Moderate drinking isn’t just good for the heart. Gallstones [40-41] and type-2 diabetes [32-43] are less common in moderate drinkers compared to non-drinkers. As elsewhere, the emphasis is on moderate drinking.
A meta-analysis of 15 prospective cohort studies, which followed 369.862 participants on average for 12 years, found that moderate drinking (0.5-4 alcoholic drinks per day) reduced the risk of diabetes by 30%. However, those who drank less or more did not benefit from this reduction. [32]
Alcohol has many social and psychological advantages. Drinking alcohol before meals can help digestion or provide a relaxing respite after a long day. A social drink with friends is also a great way to improve your mood. These social and physical effects can also improve health and well-being.
Genes Play a Role
Studies on twins, families, and adoptions have shown that genetics play a major role in determining a person’s alcohol preferences and likelihood of developing alcoholism. Alcoholism does not follow the simple inheritance rules set forth by Gregor Mendel. Instead, it is influenced by a number of genes that interact and are influenced by environmental factors. [1]
Some evidence also suggests that genes may influence the way alcohol affects cardiovascular health. An enzyme called alcohol dehydrogenase helps metabolize alcohol. This enzyme is available in two different “flavors”: one breaks down alcohol quickly and the other more slowly. Moderate drinkers with two copies of the gene encoding the slow-acting protein are at a lower risk for heart disease than those who have the two genes encoding the fast-acting protein. [44] People with two genes, one for the slower enzyme and the other for the faster one, fall somewhere in the middle.
The enzyme may act quickly to break down alcohol before it has a positive effect on HDL or clotting factors. These differences in the ADH1C genes do not affect the risk of heart disease among people who do not drink alcohol. This is strong indirect evidence to suggest that alcohol reduces the risk of heart disease.
Benefits and risks of shifting benefits and risks
The benefits and risks of moderate alcohol consumption change throughout a person’s lifetime. Risks outweigh benefits in general until middle age when cardiovascular diseases begin to take a greater share of disease burden and death.
- Moderate drinking is not recommended for pregnant women and their unborn children, recovering alcoholics, people with liver disease and those who take medications that interact negatively with alcohol.
- The increased risk of alcohol-related accidents for a man 30 years old outweighs any possible benefits to the heart from moderate alcohol consumption.
- A 60-year-old man may find that a single drink per day offers protection against heart disease, which is likely to be greater than any potential harm. (Assuming he’s not prone to alcoholism).
- The calculations of benefit/risk are more difficult for women over 60. The number of women who die from heart disease is ten times higher than the number of women who die from breast cancer. Studies show that women fear breast cancer more than heart disease. This must be taken into consideration.
The Bottom line: Balancing risks and benefits
Alcohol is a complex substance that has a variety of effects on the human body. It also affects the individuals who consume it. Therefore, making blanket alcohol recommendations is not possible. Alcohol offers a unique spectrum of risks and benefits to each individual because we all have our own personal and familial histories. It is important to carefully weigh the benefits and risks of drinking alcohol, particularly for “medicinal” purposes.
- You should be able to get help from your healthcare provider. You should consider your overall health as well as the risks of alcohol-related conditions.
- Drinking alcohol will not reduce your cardiovascular disease risk if you are physically fit, do not smoke, have a healthy diet and have no family history.
- There’s no reason to drink if you don’t. Exercise (starting to exercise or increasing the intensity and duration) or healthier eating can provide similar benefits.
- A daily alcoholic beverage could lower your risk of heart disease if you’re a man without a history of alcoholism and at moderate or high risk. A moderate drinking habit may be beneficial for those with low HDL levels who are resistant to diet and exercise.
- You must weigh the benefits of drinking daily against the slight increase in breast cancer risk if you are a woman who has no history of alcoholism and is at moderate or high risk for heart problems.
- You should limit your alcohol consumption to no more than two drinks per day for men and one drink per day for women. Make sure to get enough folate, 400 micrograms per day.
