Table of Contents
- Alcohol Flush Reaction - (i.e. Asian Flush or Asian Glow)
- Symptoms of Alcohol Flush Reaction
- What Can Trigger Asian Glow?
- Related Conditions
- Health Risks
- Using Antihistamines for Asian Flush
- What's Better Than Pepcid and Zantac?
If you suffer from Asian flush, Asian glow, alcohol flush reaction or whatever you want to call it, you’ll know exactly how embarrassing it is.
You’re not alone. With a large percentage of Asians and a notable percentage of non-Asians experiencing a red face from alcohol, the problem is widespread and relatively understudied.
We asked John, a member of the Flyby team, what it was like the first time he experienced the Asian glow:
“I remember the first time my face went red from alcohol. It was about 15 years ago and I was at a house party trying to get the interest of a girl.
The night was progressing pretty well. We were chatting and all signs were pointing in a positive direction. That was until she offered me a beer. A simple, innocent, cold, refreshing beer.
I downed it with manly gusto, trying to hide the fact that i’d never drunk a full bottle of beer before. Little did I know, this would start a 20 minute count down to me becoming the focus of the room for all the wrong reasons.
It didn’t take long before I began to feel the skin on my face heating up and beginning to tingle. Not long after that it became harder to breath and I could feel my eyes becoming bloodshot.
I could tell something was wrong by the concerned look on the girl's face. Then I heard a voice from across the room yell out “Look how smashed he is!”.
At this point everyone’s eyes were on me, my face was pulsating and quickly becoming the centre of everyone’s attention. “Are you on drugs?” she asked as she distanced herself from the laughing stock of the room.”
What a curse. Alcohol is fundamentally rooted in most societies as a means of celebration, bonding and courtship. A glass of wine on a dinner date, after work drinks, an important client lunch, a bar full of hopeful singles, the list goes on. These are all situations where having blood shot eyes, a red face and looking like you’re on drugs will not go down well.
To complicate things further, all out abstinence from drinking alcohol usually doesn’t go down too well either. Many Asian flush sufferers report feeling left out or excluded when they turn down an offer for a drink. In fact, in some cultures turning down an alcoholic beverage can be overtly rude and offensive to the person offering.
To make matters even more uncomfortable, most people are unaware that Asian flush even exists. This can cause people to make incorrect assumptions about the drinker that can potentially cause embarrassment and social awkwardness.
A recent 2018 study analyzed data from 2912 undergraduate students from 13 universities in China. The researchers found that only 11.6% of students understood the link between alcohol flushing and impaired alcohol metabolism.
This lack of awareness, especially in western countries, contributes a lot to the social hindrance experienced by people who get a red face when they drink alcohol.
2. Alcohol Flush Reaction - (i.e. Asian Flush or Asian Glow)
The condition we’re talking about here is when you get a red face shortly after consuming alcohol. This occurs because of a genetic deficiency in the way we metabolize alcohol in our liver. Simply put, when our body tries to break down alcohol it gets flooded with a metabolic by-product of alcohol called acetaldehyde.
In a healthy liver, acetaldehyde is broken down into a harmless non-toxic substance called acetate. However, in alcohol flush sufferers it isn't broken down adequately and ends up passing through the liver and into our system. This causes all kinds of unpleasant symptoms that are commonly reported to detract from the enjoyment of alcohol and cause people to feel embarrassed and self conscious.
The link between acetaldehyde accumulation and alcohol flush reaction was most famously confirmed in a 1989 study looking at the Genotypes for aldehyde dehydrogenase deficiency and alcohol sensitivity:
The alcohol-flush reaction is the result of excessive acetaldehyde accumulation, and the unpleasant symptoms tend to reduce alcohol consumption.
Most of the scientific literature is agrees that acetaldehyde is the main culprit behind the unpleasant symptoms experienced by people with alcohol flush reaction.
Let's take a closer look at acetaldehyde in order to better understand what is actually happening in our body when we react negatively to alcohol.
2.1. What is acetaldehyde?
Acetaldehyde is produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase. It is toxic and has been shown to irritate the skin, eyes, mucous membranes, throat, and respiratory tract when consumed at a high enough dosage. In this regard, it is little surprise that the symptoms of Asian glow include redness of the skin, redness and glazing of the eyes and difficulty breathing.
Acetaldehyde also poses longer term dangers, being flagged in a 1999 study by Dr. Carreón-Valencia of the International Agency for Research on Cancer as "possibly carcinogenic to humans". In 2009, the IARC confirmed this and distributed a press release in which they stated:
"Carriers of the inactive enzyme are extremely slow to metabolize acetaldehyde, as a result, they experience higher internal levels of acetaldehyde and have much higher risks of esophageal cancer and cancers of the head and neck compared with individuals with the active enzyme."
As you can see, the toxic substance causing us to experience alcohol flush reaction is also causing us serious long-term harm because of our liver’s inability to break it down.
These warnings followed strong research out of the University of Minnesota Cancer Center in Minnesota that drew a causal link between acetaldehyde exposure and DNA damage.
This was later confirmed in a 2006 study by a group of researchers from Kyoto University that concluded:
These results provide molecular evidence that the ALDH2 genotype affects the genotoxic damage caused by acetaldehyde.
In other words, the mere fact that someone experiences Asian flush can affect the degree of DNA damage caused by acetaldehyde from alcohol consumption.
The degree of this increased DNA damage was examined in a recent 2018 study by researchers from the MRC Laboratory of Molecular Biology at Cambridge. The research sought to show that damage to DNA in blood stem cells caused by acetaldehyde is the main culprit of the increased cancer risks highlighted by the IARC. Experimenting on mice, the researchers were able to show that subjects with the Asian flush gene suffered 4 times more DNA damage from alcohol than subjects without the gene mutation.
Why is it that people with Asian flush can’t we break down acetaldehyde like normal consumers of alcohol? The problem originates from an obscure enzyme that goes by the name of ALDH2.
2.2. What is the ALDH2 enzyme?
Mitochondrial aldehyde dehydrogenase (ALDH2) is an enzyme that is encoded by the ALDH2 gene.
The main purpose of this enzyme is to break down acetaldehyde into harmless acetate during the metabolism of alcohol.
As we’ve seen above, not only does this protect us from the likes of Asian glow, but it also ensures we are not exposed to the long-term health effects of acetaldehyde exposure mentioned above.
It is estimated that approximately 50% of East Asians are born with a genetic ALDH2 deficiency with a smaller percentage of Causcasians being affected. That said, alcohol flush reaction in Causasians is not as uncommon as one might think. In fact, according to a 1986 study looking at the racial differences in alcohol sensitivity, approximately 3 to 29 percent of Caucasians get a red face from alcohol.
Regardless of one's race, people get alcohol flush reaction because they inherit a deficient ALDH2 gene from their parents, who inherited it from their parents, and so on.
As a result of its genetic origin, people are often told they can't do anything about ALDH2 deficiency and usually advised to abstain from alcohol if they don't like going red in the face.
However, whilst the enzymatic deficiency is permanent, it doesn’t mean the function of the enzyme can’t be assisted in such a way that enables it to break down acetaldehyde like any normal healthy liver.
To understand how to do this, we need to have a look at the various symptoms of Asian flush and how they are triggered.
Before we do that, if you would like to explore this topic in more detail, feel free to check out our article about ALDH2 deficiency.
3. Symptoms of Alcohol Flush Reaction
As Alexi points out in the video, the most embarrassing symptom of Asian flush is a bright red face, usually accompanied by slight swelling around the flush affected areas.
Other symptoms include:
- Redness of face and upper body (i.e. the Asian flush)
- Swelling of the cheeks
- Red eyes
- Difficulty breathing
Looking well presented and attractive is challenging enough without having to do so with a swollen red face. Think about the amount of time we spend shopping for nice clothes, doing our hair, makeup or whatever it is so that we can look our best for an important business lunch, dinner date or any kind of public social gathering. If you’re unlucky enough to have alcohol flush reaction then all of this effort goes down the drain after half a beer - and those of you nodding your head know exactly what we’re talking about.
Not only that but you can also throw in a pair of bloodshot red eyes, glazed over like you’ve spent the whole day smoking you know what. This is not a good look, especially if you’re trying to maintain a well presented image in a business context.
Despite this, a 1991 study looking at the subjective feelings of people with Asian flush concluded that:
This alcohol sensitivity reaction that many Asian flushers experience may contribute to their lower tendency to drink excessively, even though their response to alcohol is not predominantly negative.
In this study, researchers divided subjects into two groups. One group with a functioning ALDH2 enzyme and another with the enzyme deficiency that causes alcohol flush reaction.
After administering alcohol to both groups, researchers asked the subjects to rate the positiveness of their intoxication.
Surprisingly, the results showed that subjects with alcohol flush reaction reported more positive feelings of intoxication than the non flushing group:
Following alcohol, flushers reported experiencing significantly more positive feelings of intoxication than non-flushers, despite equivalent blood alcohol concentrations. These data suggest that Asians who flush after drinking, particularly those with ALDH2*1/2*2 genotype, have a more intense, although not necessarily a more negative, response to alcohol than comparable non-flushing Asians.
Despite these conclusions, the success of many pharmaceutical answers to alcoholism seem to contradict these findings.
There are drugs made specifically to cause symptoms of Asian flush after consuming alcohol and work as a deterrent to alcoholics continuing their addiction.
Not only this, we have worked closely with thousands of people who have shared their subjective experiences of alcohol flush reaction with us. The truth is, this is not a positive experience. In fact, the symptoms are usually sufficiently negative to turn them off drinking alcohol altogether.
In addition to this, we have also dealt with thousands of people who have managed to stop their flushing symptoms. Out of this group, the overwhelming feedback is that their subjective experience of alcohol consumption was dramatically improved when their Asian flush went away - not the other way around as the above study suggests.
4. What Can Trigger Asian Glow?
The symptoms of Asian glow above are triggered by an acetaldehyde induced histamine release. If our livers could process acetaldehyde properly we would release fewer histamines and be able to enjoy drinking without a red face just like everyone else.
Luckily the amount of acetaldehyde our bodies are required to process, and the resulting severity of our red faces, can be controlled by managing the triggers at all stages of the flushing process.
To do this we need to look at what happens from the moment alcohol enters our system, on to when it is processed by our livers, and finally when it causes our red face. Doing this allows us to understand, dissect and counter the triggers at multiple stages of the flushing process.
4.1. What are you drinking?
There are many additives used in the production of alcohol that can worsen the effects of Asian flush. Being aware of the kinds of alcohol that contain such additives and avoiding them can reduce the histamine load the body is required to handle.
On such example is aged spirits. These are usually stored in wooden barrels for many years and as a result tend to accumulate molecules called tannins that have been shown to cause a minor histamine re-action in some people. This can exaggerate symptoms in people with Asian glow who are already trying to deal with the histamines from acetaldehyde.
Another example is red wine, which contains high amounts of tannins because of its dark color and the oak barrels it is usually stored in. White wine can also have tannins too, so it is advisable to check online for commercially available low-tannin varieties of wine such as Beaujolais and Tempranillo.
Another alcohol additive to watch out for is sulphites. Beer and cider both contain sulphites that have been shown to cause many people various unpleasant symptoms such as headaches and flushing. Combine this with the toxic effects of acetaldehyde and you’ve got yourself an Asian glow blow out!
But wait a second, if aged spirits, wine and beer are all potential triggers of Asian flush, what is there left to drink? This was the precise question that confronted the guys at Flyby when dissecting the additives in these common alcoholic beverages.
In answer to this, they put together a highly comprehensive cocktail recipe guide, specifically designed with alcohol flushing in mind.
4.2. Deficient liver enzymes
As mentioned above, the flush inducing toxins in alcohol are usually broken down by the ALDH2 enzyme. People who flush from alcohol have a deficiency in this liver enzyme and this triggers a flow on effect that causes Asian flush.
To correct for this deficiency, the ALDH2 enzyme can be assisted by glutathione, one of the most powerful anti-oxidants the body can handle.
According to a 2007 study looking at glutathione depletion and recovery after acute ethanol administration, researchers indeed affirmed the role of glutathione in breaking down the toxins from alcohol consumption. However, they also concluded that it gets depleted rapidly whenever alcohol is consumed.
In 2015, researchers at the Brandenburg University of Technology Cottbus-Senftenberg in Germany confirmed this in a study that looked at how alcohol consumption affects the body's natural ability to regenerate levels of inter-cellular glutathione in the liver. They concluded that long term ethanol exposure does indeed affect our body's ability to regenerate glutathione.
This is why it is important to replenish the body's glutathione levels before and even during the consumption of alcohol. This ensures that the body has enough of it to compensate for the shortcomings of its deficient liver enzymes.
Whilst glutathione does an excellent job of assisting the deficient ALDH2 enzyme, it is not perfect. As a result, there’s always some acetaldehyde left behind that causes our bodies to release flush causing histamines.
This was confirmed in a 1998 study looking at the effect of acetaldehyde on mast cells (i.e. the main source of histamine in a mammal's body). The study concluded that: acetaldehyde, already at a concentration of 50 μM, significantly increases the release of histamine from mast cells. Ethanol has a similar effect but only at molar concentrations. These results indicate that acetaldehyde may contribute to the development of various hypersensitivity reactions by directly increasing histamine release from mast cells.
This is why a lot of people with alcohol flush reaction partake in the dangerous off-label use of antihistamines to alleviate their symptoms.
As we will discuss later, antihistamines such as Pepcid AC and Zantac are severely outdated and pose unnecessary risks when taken with alcohol.
5. Related Conditions
As mentioned above, there are many additives in alcohol that can cause unwanted side effects independent from alcohol flush reaction itself. Because of this, many people have incorrectly classified the Asian flush syndrome as an allergy to alcohol.
This is not the case. Furthermore, it should be noted that an allergic reaction to alcohol is extremely rare and, given the quantity of alcohol in one standard drink, a real allergy to alcohol can be devastatingly severe and sometimes even result in death.
The more likely explanation for a reaction to alcohol is sensitivity to one of the ingredients used in its production.
Many beverages contain traces of yeast, wheat and even dairy to only mention a few. This is why if you have food allergies it is very important to be aware of the contents of every alcoholic beverage you consume to ensure there are no additional flush causing catalysts hiding inside.
6. Health Risks
Up until now we’ve focused on the short-term symptoms of Asian flush in the form of a red face, headaches, restricted breathing, etc. These are symptoms come in the way of enjoying alcohol and therefore it’s no surprise that they usually command the spotlight of most of the discussion about the topic.
What is often overlooked are the more serious longer term risks. We’ll assume you’re all aware of the long-term risks of alcohol consumption in general. These are important considerations for anyone consuming alcohol on a regular basis. But what a lot of people don’t know about are the additional long-term risks specific to people with ALDH2 deficiency (i.e. Asian flush).
In 2009, scientists from the National Institute on Alcohol Abuse and Alcoholism (NIAAA) and Japan's Kurihama Alcohol Center conducted a study which showed a link between alcohol flushing and esophageal cancer, concluding that:
“ALDH2 efficiency resulting from the ALDH2 Lys487 allele contributes to both the alcohol flushing response and an elevated risk of squamous cell esophageal cancer from alcohol consumption.”
This research was subsequently picked up and released to the public by the National Institutes of Health in a press release, going on to say:
“Dr. Brooks cites the high mortality from esophageal cancer and the large number of individuals with the deficient enzyme, known as aldehyde dehydrogenase 2 (ALDH2).”
These findings have also been confirmed by the International Agency for Research on Cancer and have supported their move to classify acetaldehyde as carcinogenic to humans. Not only that, but they go on to describe various other dangers of sustained acetaldehyde exposure such as DNA damage and abnormal muscle development.
With such an emphatic warning now considered to be factually and scientifically sound, it is surprising that most Asian flush sufferers are completely unaware of the long term dangers they face as a result of their deficient ALDH2 enzyme.
In 2009, Lisa Ye at the University of Guelph wrote a literary review titled Alcohol and the Asian Flush Reaction. n her review she reiterates these serious warnings and calls for governments to come together to educate the population about what she sees as a serious public health risk that is being ignored:
Due to severity of the public health implications, it is important to educate and raise awareness of this health risk and explore a harm reducing method in order to facilitate safe alcohol consumption for affected individuals.
This further emphasizes the importance of being conscious about the amount of acetaldehyde that is entering our bodies when we drink alcohol and the various methods we can use to reduce it.
This brings us to an important point. Why consume alcohol in the first place? Especially if one is subject to higher health risks as a result of their alcohol flush reaction. Doesn't it just make sense to abstain from drinking altogether?
The answer to this is explored in a 2005 study looking at the relationships between alcohol, aldh2 and esophageal cancer. In this study the researchers found:
...strong evidence that alcohol intake increases the risk of esophageal cancer and individuals whose genotype results in markedly lower intake, because they have an adverse reaction to alcohol are thus protected.
In other words, the researchers in this study are saying that, even if you have alcohol flush reaction, you can avoid these health risks by avoiding alcohol consumption.
This is, without a doubt, the safest option. However, this safety comes at a social cost given how prevalent alcohol is in our societies today.
Therefore, it is understandable that people with alcohol flush reaction may want to continue consuming responsible amounts of alcohol in a social context.
Luckily our bodies provide us with a warning signal by exhibiting the unpleasant symptoms of Asian flush that we know all too well. This means that we can know when we are being exposed to too much acetaldehyde and begin to do something about it.
You can read more about the health risks specific to people with Asian flush in our article titled: Asian Flush Cancer - Debunking the Myth.
7. Using Antihistamines for Asian Flush
The problem with using antihistamines to mask your alcohol flush reaction is that it ignores the root cause of why it is happening in the first place.
As we discussed above, the root cause of the flushing is acetaldehyde exposure and, if you recall from the previous section, this can dramatically increase health risks specific to people who experience flushing from alcohol.
By simply masking the unpleasant side effects and doing nothing about the amount of acetaldehyde your body is exposed to, the use of Pepcid (famotidine) and Zantac (ranitidine) can cause you to consume more acetaldehyde than you otherwise would and put you at greater risk of these health risks.
This was confirmed in a 1988 study looking at the effect of ranitidine and famotidine on ethanol metabolism. The researchers tested a group of Japanese subjects and found that ranitidine (Zantac) and famotidine (Pepcid) had little to no affect on blood acetaldehyde after ethanol metabolism.
This adds weight to the inference that the off-label use of these antihistamines is misguided. Whilst some users report favorable symptomatic effects, there is a real danger of this leading to over consumption of alcohol and undetected acetaldehyde accumulation by people with alcohol flush reaction.
8. What’s Better Than Pepcid and Zantac?
The use of antihistamines like Pepcid and Zantac by alcohol flushers started back in the 80’s after a study found a link between the use of such antihistamines and the severity of a person’s alcohol flush response.
But we’re not in the 80’s anymore and science has since come a long way in determining the best way to drink alcohol without a red face - and it’s not with pharmaceutical antihistamines.
The key was in understanding that alcohol flush reaction can be addressed from two important angles rather than just one.
Firstly, the body’s ability to break down acetaldehyde needs to be boosted to the level and functionality of a person who doesn’t have Asian flush.
Secondly, the body’s histamine defenses must be primed and ready to stop any reaction to the acetaldehyde that sneaks through the first line of defense.
In order to achieve this you can’t simply rely on popping an antihistamine and hoping for the best. The various compounds required for this level of defense need to be balanced to perfection in order to allow for the right amount of glutathione synthesis to occur whilst also maintaining an adequate level of histamine defense to finish off the job.