We often get mixed messages about alcohol use. Moderate amounts have been linked to health benefits, but it is also addictive and highly toxic — especially when you drink too much. The truth is that the health effects of alcohol vary between individuals and depend on the amount and type of alcohol consumed.
What is alcohol?
The main active ingredient in alcohol beverages is ethanol. It is produced by yeasts that digest sugar in certain carb-rich foods such as grapes or grains which are used to make wine and beer respectively.
When we drink alcohol, the effects of alcohol on us depends on its concentration in the blood. The blood alcohol concentration is determined by how quickly alcohol is absorbed, distributed, metabolised, and excreted. The alcohol elimination rate varies widely (ie. three-fold) among individuals and is influenced by factors such as chronic alcohol consumption, diet, age, smoking and time of day.
Alcohol elimination is largely dependent on our liver, by producing alcohol-metabolising enzymes alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH2). Fatty liver gradually develops in 90% of those who drink more than a 1/2 ounce (15 ml) of alcohol per day and is usually symptomless and fully reversible. In heavy drinkers, binge drinking may cause your liver to become inflamed. In worst-case scenarios, liver cells die and get replaced with scar tissue. This leads to a serious condition called cirrhosis. Cirrhosis is irreversible and associated with many serious health problems.
Alcohol’s impact on our brain
Alcohol reduces communication between brain cells causing a short-term effect responsible for many of the symptoms of being drunk. While alcohol intoxication is only temporary, chronic alcohol abuse can impair brain function permanently, increase your risk of dementia and cause brain shrinkage in middle-aged and older adults. However, moderate drinking may have benefits for brain health, especially among older adults.
Alcohol abuse and depression are linked. People may start abusing alcohol due to depression or become depressed by abusing alcohol.
Alcohol’s impact on our body weight
Alcohol is the second most calorie-rich nutrient after fat — packing about 7 calories per gram. Beer has a similar number of calories as sugary soft drinks, ounce for ounce, whereas red wine has twice as much. However, studies investigating the link between alcohol and weight have provided inconsistent results. Heavy drinking and beer are linked to increased weight gain, while moderate drinking and wine are linked to reduced weight gain or even weight loss.
Alcohol’s impact on pregnancy
Binge drinking early in pregnancy is particularly risky for the developing baby. In fact, it may have adverse effects on development, growth, intelligence and behaviour — which may affect the child for the rest of its life.
Alcohol’s impact on heart
The relationship between alcohol and heart disease is complex and depends on several factors. In general, light to moderate alcohol consumption may reduce your risk of heart disease, heavy drinking may increase it.
What is the best practise for alcohol consumption?
Red wine may be one of the healthiest alcoholic beverages, probably due to its high concentration of antioxidants. That said, consuming high amounts does not provide greater health benefits. Heavy drinking causes health problems — regardless of the type of beverage.
Recommendations for alcohol intake are usually based on the number of standard drinks per day. Below is an image of a standard drink for different type of alcoholic beverage.
| 12 fl oz of regular beer | 8-9 fl oz of malt liquor (shown in a 12 oz glass) | 5 fl oz of table wine | 1.5 fl oz shot of 80-proof spirits (“hard liquor – whiskey, gin, rum, vodka, tequila, etc.) |
|---|---|---|---|
 |  |  |  |
| 12 oz = 350ml | 8-9 oz = 250ml | 5 oz = 150ml | 1.5 oz = 45ml |
The percent of “pure alcohol, expressed here by volume (alc/vol), varies by beverage.
Moderate drinking is defined as one standard drink per day for women and two standard drink per day for men.
Drinking patterns are also important. Binge drinking is a form of alcohol abuse and can cause harm.
