Before Dry July goes into “full swing”, why not learn some key facts about alcohol and health

Alcohol and health are both important public health issues. Excessive alcohol consumption is linked to over 200 diseases. This month, support the Dry July campaign and go without a drink for as long as you can.

Alcohol has been called many things: a drug, a toxic and psychoactive substance or an inebriant. Others called it a drink, an aperitif, or a tonic. Regardless of how it is called, alcohol is one of human’s oldest drinks, going back thousands of years.

The oldest confirmed evidence of alcohol consumption was found in a 7,000 old Chinese pottery, containing chemical evidence of purposeful fermentation. But the affair of humans with alcohol goes back much further in time and has important implications.

This month, the Dry July initiative is asking you to put down that drink and stay alcohol-free for as much as you can. Take this opportunity to support Dry July and stay alcohol-free. While you are working on this, learn a bit about the history and health consequences of alcohol on your health.


A 10 million-year-old drinking habit


Humans’ taste for alcohol is very ancient, and research shows it is hardwired into our lineage. Our primate ancestors had a taste for over-ripened fruit, some containing as much a 4% alcohol. They even evolved a variation of a gene called ADH4, which creates an enzyme that is highly efficient at metabolizing ethanol, the drinkable form of alcohol1. This happened about 10 million years ago and hints at just how long ago our lineage has been consuming ethanol.

Today, alcohol consumption is linked to virtually every human culture and dates back thousands of years. Multiple cultures around the world have been consuming and producing alcohol, through the fermentation of different foods containing sugars or starch, like fruits roots and grains.



What is alcohol, anyway?


From a chemical and physical perspective, alcohol is somewhat similar to water. Chemically, both water and alcohol contain oxygen and hydrogen atoms in their structure, but alcohol is much more complex. From a physical perspective, both alcohol and water look like transparent liquids, but their properties are quite different and some alcohol can be poisonous to your health.

There are many different types of alcohol, but only one, ethanol or ethyl alcohol, is found in alcoholic drinks like beer, cider, malt liquor, wines, and distilled spirits. Ethanol is formed through the process of yeast fermentation of sugars or starches found in fruits, starchy grains and some roots. Anything from grapes, apples, bananas, pineapples, and persimmons to birch tree sap, cacao, cassavas, corn, rice, sweet potatoes or pumpkins have been used to create a fermented product. Even mare milk has been used to make a fermented drink, called kumis.



How ethanol is processed in your body


Once inside your body, ethanol is processed in various steps. First, a small portion of the alcohol you drink is absorbed by the tongue and the mucosal lining of the mouth. Most of the alcohol ends up in the stomach, where it is absorbed through the lining of the stomach and small intestine and enters the bloodstream. Once in your blood, ethanol reaches every organ and tissue in your body, except for fat and bones.

The main step of alcohol processing occurs in the liver, where the enzyme alcohol dehydrogenase (ADH) breaks down ethanol into acetaldehyde, a carcinogen substance. Normally, this compound is quickly processed by another enzyme, called aldehyde dehydrogenase, and converted into acetate, which is further processed, outside the liver, into carbon dioxide and water.

How fast someone process alcohol depends on multiple factors, including age, sex, time of the day, and whether you have eaten recently.

  • Women, for example, have been shown to have faster alcohol elimination rates than men2
  • Aged people, who might experience a decrease in enzymatic function, process alcohol less efficiently3
  • Being fed also influences our capacity of metabolizing ethanol, mostly because after eating our levels of the ADH enzyme are higher
  • Biological rhythms may also influence alcohol metabolism. An animal study, for example, showed that optimal metabolism occurs late at night4. In humans, studies show the inebriating effects of alcohol occur more prominently at night, likely due to a decrease in enzymatic function5-6.


From a physiological perspective, alcohol is considered a toxin that must be processed into less toxic components and eliminated from the body. Alcohol is eliminated from the body through various mechanisms, including:

  • Through sweat, breath and urine. About 10% of the alcohol you ingest dissipates this way.
  • Liver metabolism, most of the remaining ethanol in your body is processed by your liver.



Excessive alcohol and health


According to figures from the World Health Organization, alcohol and health don’t mix. Alcohol contributes to 3 million deaths every year around the world and it is directly involved with the development of more than 200 diseases and injury conditions.

The link between alcohol and health is complex, and studies have shown that both our physical and mental health are affected by excessive alcohol intake.


Physical Effects


      • Cancer development

        Excessive alcohol consumption has been associated with increased risk of developing cancer in organs and tissues of the respiratory tract and the upper digestive tract, as well as in the liver, colon, rectum, and breasts7. Various mechanisms have been proposed to explain how this happens, including:

        • Ethanol metabolism – in your liver, ethanol is broken down into acetaldehyde, which is a considered a human carcinogen, as it damages DNA and proteins7.


        • ROS production – ROS or reactive chemical species are chemical molecules containing oxygen that interact with biomolecules in your body. ROS are common by-products of alcohol metabolism, and they can damage DNA, proteins, and fat tissues through oxidation8-9.


        • Impaired nutrition – ethanol consumption can inhibit the body’s ability to break down and absorb micronutrients like vitamin A, folate, vitamins C, D and E and carotenoids. Low levels of these micronutrients have been linked to increased cancer risk10.


        • Estrogen levels – alcohol intake can lead to increased levels of estrogen, a sex hormone that has been linked to increased risk of breast cancer11.


      • Impaired immune function

        Heavy alcohol use has been shown to have inflammation-producing and immune-suppressing effects in our body. While the mechanisms in place are not well understood, studies have shown that alcohol can reduce the function of macrophages through oxidative stress. Macrophages are important immune cells involved in our innate immune response against pathogens12.


      • Dysregulation of the HPA axis and hormones

        Chronic alcohol use has been shown to impair the inhibitory control of the HPA axis, resulting in altered levels of hormones like cortisol, as well as influencing levels of other hormones, outside the HPA axis, such as androgen, estrogen and testosterone13-16.


      • Organ-specific health effects

        Heavy drinking has been shown to cause health problems in multiple organs, including:

        • Brain function – alcohol can affect concentration, judgement, mood, and memory, and increase your chances of developing dementia or having a stroke17-18.


        • Heart disease – alcohol can increase your blood pressure, potentially leading to heart damage or even heart attacks19.


        • Liver disease – daily alcohol intake can increase your risk of liver cancer and cirrhosis20.


        • Stomach problems – stomach and bowel cancer are linked to excessive alcohol intake21.


      • Gut microbiome dysbiosis and altered intestinal barrier function

        Excessive alcohol intake affects the composition of the gut and oral microbiota, causing dysbiosis. Dysbiosis is characterised by low levels of gut-specific groups of beneficial bacteria, such as Faecalibacterium and an overrepresentation of bacteria with known proinflammatory effects, like Proteobacteria and Sutterella22-24. Chronic alcohol use has also been linked to decreased intestinal barrier function, through its effect promoting the growth of Gram-negative bacteria. These bacteria metabolise alcohol and produce acetaldehyde, which is known to increase intestinal permeability25.


Hence, if you suffer from conditions like small intestinal bacterial overgrowth (SIBO), Irritable Bowel Syndrome (IBS), or gastroesophageal reflux disease, you should avoid alcohol completely.


Mental Effects


Excessive alcohol consumption is also well-known for its effects on our behaviour and its capacity to decrease our inhibitions, including a tendency towards unhealthy eating habits that can lead to fat gain and other health problems.

      • Although the mechanism is not fully understood, alcohol has been shown to have an important appetite-enhancing effect26.


      • The decrease in our inhibitions is also linked to poor behavioural choices, which can result in harm.


      • Depression, anxiety, and poor mental health have also been associated with alcohol abuse27-28.


Everything in excess is bad. The link between alcohol and health is a clear example. The physical and mental consequences of excessive alcohol intake are well documented and following the goals of Dry July will be a positive first step towards a healthier lifestyle.

By supporting the Dry July initiative, you will not only be supporting a worthy cause, you will also be optimizing your health.


A short guide to drinks – naughty and nice


This dry-July, you don’t need to be stuck drinking just water and coffee. There is a whole world of drinks out there that are alcohol-free. Some favourites include:


      • Kombucha; perhaps the most popular probiotic drink out there, Kombucha concoctions have multiple purported health benefits, like benefiting your gut bacteria or even reducing the risk of heart disease or diabetes. There are multiple options to choose from in supermarkets, just watch out for the sugar content to make sure you are not getting more than your daily recommended limit.


      • A top homemade alternative is club soda or mineral water with sliced fruit. Think limes, oranges, grapefruits, topped with some mint leaves.


      • If none of the commercially available Kombucha drinks work for you, why not try making your own mixtures. You can start with this wicked raspberry kombucha mocktail.


For more ideas on alcohol-free drinks, have a look at the top 10 list from BBC good food, or learn about a new generation of low and alcohol-free spirits.


Dry July naughty drink ideas


When thinking about alcoholic drinks, there are healthier alternatives than your usual beer or sweet cocktail.


      • For all Kombucha lovers, there is a loaded new alternative, called dirty kombucha, which mixes your beloved fungal tea with gin or vodka.


      • Another good, low-calory option are cocktails made of club soda, vodka, or gin plus a sliver of lime, orange or grapefruit.


      • Red wine is another good alternative. Try searching for low sugar, such as dry red (Pinot Noir, Cabernet Sauvignon, and Shiraz). Also worth considering organic wines, which are made from grapes free of pesticides or other chemicals. Also, look for preservative-free wines which do not contain sulphites or other preservatives. Learn more about sulphites in wine before worrying too much about them.




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