Table of Contents
- 1 Alcohol use stats and figures
- 2 Alcohol and thyroid hormones
- 3 How does alcohol affect the thyroid?
- 4 Autoimmune thyroid disease and alcohol
- 5 Alcohol raises estrogen and affects liver health
- 6 Thyroid and treatment of alcoholism
- 7 Conclusion
- 8 References
Most people drink alcohol at one point or another. Sometimes you have a drink or two to relax after long day at work, maybe you only drink when celebrating anniversaries, birthdays, or promotions.
However, it’s not uncommon for people to engage in binge-drinking sessions more often than they’d like to admit. Alcohol use plays a role in your health and wellbeing.
Some effects of alcohol are well-known, but others not so much.
Throughout this post, we’re going to learn if alcohol has an impact on thyroid health and function.
Alcohol use stats and figures
Alcohol use is nothing uncommon today, which is best depicted by results of a survey published by the National Institute on Alcohol Abuse and Alcoholism[i]:
- “86.4% of people ages 18 or older drink alcohol at some point in their lifetime”
- “70.1% drank alcohol in the past year”
- “56% had an alcoholic beverage in the past month”
- “26.9% of people ages 18 or older engaged in binge-drinking sessions in the past month”
- “7% people reported heavy alcohol use in the past month”
- “15.1 million adults, or 6.2% of people who are 18 or older, had alcohol use disorder (AUD). Of these, 9.8 million are men and 5.3 million, women”
- “88,000 people die from alcohol-related causes annually. This means that alcohol use is the third leading preventable cause of death in the US”
- “Of 78,529 liver disease deaths, about 47% are attributed to alcohol use”
- “Alcohol-related liver disease is the primary cause of 1 in 3 liver transplants in the US”
The above-mentioned figures reveal alcohol use, including excessive intake, is a common occurrence with potentially devastating consequences.
Sure, moderate intake of certain alcoholic drinks such as red wine can exhibit beneficial effects, but generally speaking, continued excessive use of alcohol itself is bad news for your health.
How does it affect the thyroid?
Alcohol and thyroid hormones
Although occasional and moderate consumption of alcohol doesn’t cause long-lasting harm to thyroid, when taken regularly alcoholic beverages can affect all aspects of the functioning of the thyroid gland and the hypothalamus-pituitary-thyroid (HPT) axis.
Scientific evidence about the influence of chronic alcohol intake on thyroid hormones is limited due to the fact scientists face difficulties recruiting active drinkers into their research. That being said, current data shows that alcohol use has a negative influence on the production of hormones and thyroid levels.
The intake of alcohol causes a moderate suppression of peripheral thyroxine (T4) levels while the suppression of triiodothyronine (T3) is more significant. Studies also demonstrated that response of TSH to TRH is different in alcoholism than in depression.
The discovery came after scientists carried out a study to inspect the hypothesis that alcoholic and depressed men have a decreased response of TSH to thyrotropin-releasing hormone (TRH)[ii].
Interestingly, a study from the Drug and Alcohol Dependence confirmed the existence of euthyroid sick syndrome[iii] where alcohol-dependent persons can have low levels of T3, high levels of reverse T3 or rT3, and normal levels of the T4 hormone.
Reverse T3 is a metabolite of T4. Under normal circumstances, T4 is converted to T3, but in some cases, the body converts it to rT3 to conserve energy.
Bearing in mind rT3 is an inactive form of much-needed T3 hormone it is unable to deliver oxygen and energy to cells. Basically, even when a person has sufficient levels of T4, the inability to convert it to T3 means the body can’t utilize the hormone which leads to deficiency and symptoms associated with it.
Alcohol and size of thyroid gland
Although seemingly harmless, alcohol has a direct toxic effect[iv] on thyroid cells. The toxicity, induced by use of alcohol, could also contribute to thyroid volume reduction in active drinkers. Studies show that toxic effect of alcohol on thyroid is independent of the degree of liver damage[v].
Due to its toxicity effect which reduces thyroid volume, alcohol intake is associated with reduced prevalence of goiter and solitary thyroid nodules, according to a study that involved 4649 men and women from Denmark[vi].
The decreased volume of the butterfly-shaped gland is followed by a decline in T3, free T3 concentrations while TSH and T4 values remain normal. That being said, healthy functioning of this gland requires sufficient concentration of both T3 and T4.
While many studies have confirmed toxic effects of alcohol on thyroid cells and decreased volume, one research discovered the opposite. A study from the journal Clinical Endocrinology enrolled 1493 participants and found that alcohol intake was strongly associated with higher thyroid volume regardless of the iodine status[vii].
More research is necessary to determine whether alcohol could, indeed, lead to a higher volume of the thyroid gland. Despite this conflicting report, it’s easy to conclude that regular drinking exhibits direct effects on the gland size and, thereby, influences its functions.
How does alcohol affect the thyroid?
The negative influence of alcohol on thyroid functions are well-documented, as seen above, but it’s impossible not to wonder about the underlying mechanisms. How does alcohol affect this gland exactly?
The mechanism of alcohol-induced damage to the thyroid is poorly described and open to speculation and additional studies on this subject. One theory is the down-regulation of TRH receptors in the pituitary gland due to excessive concentration of TRH.
Levels of TRH tend to rise with a decline in the peripheral concentration of thyroid hormones. Also, TRH can increase when the body requires greater amounts of both T3 and T4. In the chronic consumption of alcohol (and even in the earliest stages of abstinence), thyroid hormone levels are low, thus causing the higher release of TRH.
This leads to the above-mentioned suppression of receptors and interrupted secretion of TSH.
This theory could be the most likely explanation behind the influence of alcohol on thyroid and different studies have confirmed it. For example, one research found that chronic ethanol treatment in rats elevated TRH messenger RNA (mRNA) in hypothalamic neurons. The study also confirmed that alcohol use alters the functioning of the HPT axis[viii].
Autoimmune thyroid disease and alcohol
Autoimmune thyroid diseases like Hashimoto’s thyroiditis are common and it was only a matter of time scientists would choose to investigate how alcohol affects one’s risk of developing them. The European Thyroid Journal published an interesting study which involved 803 participants from the Amsterdam AITD (autoimmune thyroid disease) cohort.
Results showed that alcohol, actually, decreases the risk of the development of overt hypothyroidism in subjects who were considered susceptible to develop AITD. Scientists concluded the study explaining that consumption of >10 units/week exhibits protective effects against the development of autoimmune thyroid disease[xi].
It’s important to mention that excessive intake of alcohol didn’t have protective effects and it didn’t reduce the risk of developing AITD. The relationship persisted even when scientists adjusted results according to parameters such as smoking.
Alcohol raises estrogen and affects liver health
Alcohol contains phytoestrogens which elevate levels of the hormone estrogen in your body[xii]. Even the moderate intake of your favorite alcoholic drink can increase the concentration of estrogen and cause hormonal imbalance.
In addition, alcohol consumption enhances the activity of aromatase enzyme. This particular enzyme heightens the conversion of testosterone and other androgens into estrogen. The action strengthens estrogen dominance and hinders thyroid function and hormone secretion.
As you’re already aware, excessive drinking is harmful to your liver and hinders its detoxifying properties. The liver has an important job to eliminate toxins out of your body. In cases when the liver is unable to perform detox properly, high levels of estrogen remain in your tissues and further contribute to thyroid dysfunction.
That’s because conversion of T4 into T3 takes place in your liver. In order for the thyroid to function properly, the liver needs to be healthy too.
Thyroid and treatment of alcoholism
Binge-drinking and alcoholism are harmful to your overall health and wellbeing. They also increase the risk of car accidents, injuries, and high-risk behaviors.
Throughout this post, you also had the opportunity to see that alcohol affects thyroid in both direct and indirect manner. A person with a drinking problem can improve their health and quality of life through treatment measures and support from family and friends.
Treatment of alcoholism can involve the intake of medications whose purpose is to alleviate withdrawal symptoms. The intensity of these symptoms varies from one person to another and depends on the severity of drinking problem.
Some of these drugs can interfere with thyroid function too. The most frequently used medications for this purpose are benzodiazepines which are considered safe for thyroid.
Studies show that diazepam absorption increases in hypothyroid, but not in hyperthyroid rats[xiv]. The continuation of abstinence usually involves the use of medications such as disulfiram which has an anti-thyroid effect and reacts in a manner that induces iodine deficiency, or it doesn’t allow thyroid to use iodine adequately.
When a person starts abstaining from alcohol, changes in thyroid occur immediately. One study inspected the consequences three weeks after abstinence from drinking and discovered that free T3 (fT3) levels remained lower than in healthy participants. Results also revealed that rT3 levels moderately decreased while TSH values remained normal. Levels of T4 and T3 also increased[xv].
Furthermore, a group of scientists from Greece carried out a separate study and discovered that after completion of alcohol abstinence and detoxification, most measurements returned to normal levels. The research also highlighted the correlation between thyroid hormones levels and hepatic enzymes as well as mood status.
The study also confirmed excessive alcohol negatively affects HPT axis, but it’s great news to see measurements can be returned to normal after you stop drinking. These measurements involve T3, T4, TSH, hepatic enzymes, anxiety, and depression[xvi].
How many drinks are considered moderate drinking?
Most studies on alcohol involve heavy or binge-drinking and their effects. Heavy drinking is defined as consuming 15 or more drinks a week for men and 8 drinks for women.
On the other hand, binge drinking is a pattern of alcohol consumption that causes blood alcohol concentration of at least 0.08%. This usually occurs after consuming 5 or more drinks per occasion for men and 4 for women, though its primarily based on your weight.
We are usually advised to drink alcohol moderately (in case a person doesn’t want to eliminate it entirely), but what does moderate intake mean? Moderate drinking is defined as having 1 drink a day if you’re a woman and 2 drinks if you’re a man.
Most people drink alcohol due to a wide array of reasons.
Alcohol negatively affects your health, including thyroid.
Excessive drinking can hinder the production of hormones, disturb the functioning of HPT axis, and disrupt thyroid function in both direct and indirect manner.
[i] Alcohol facts and statistics, National Institute on Alcohol Abuse and Alcoholism https://www.niaaa.nih.gov/alcohol-health/overview-alcohol-consumption/alcohol-facts-and-statistics
[ii] Garbutt JC, Mayo JP, Little KY, et al. Dose-response studies with thyrotropin-releasing hormone: evidence for differential pituitary responses in men with major depression, alcoholism, and no psychopathology. Alcoholism, Clinical and Experimental Research 1996 Jun;20(4):717-22 https://www.ncbi.nlm.nih.gov/pubmed/8800390/
[iv] Hegedüs L. Decreased thyroid gland volume in alcoholic cirrhosis of the liver. Journal of Clinical Endocrinology and Metabolism 1984 May;58(5):930-3. Doi: 10.1210/jcem-58-5-930 https://www.ncbi.nlm.nih.gov/pubmed/6707193/
[v] Hegedüs L, Rasmussen N, Ravn V, et al. Independent effects of liver disease and chronic alcoholism on thyroid function and size: the possibility of a toxic effect of alcohol on the thyroid gland. Metabolism 1998 Mar;37(3):229-33 https://www.ncbi.nlm.nih.gov/pubmed/3343931/
[vi] Knudsen N, Bülow I, Laurberg P, et al. Alcohol consumption is associated with reduced prevalence of goiter and solitary thyroid nodules. Clinical Endocrinology 2001 Jul;55(1):41-6 https://www.ncbi.nlm.nih.gov/pubmed/11453951/
[vii] Valeix P, Faure P, Bertrais S, et al. Effects of light to moderate alcohol consumption on thyroid volume and thyroid function. Clinical Endocrinology 2008 Jun;68(6):988-95. Doi: 10.1111/j.1365-2265-2007.03123.x https://www.ncbi.nlm.nih.gov/pubmed/18031329/
[viii] Zoeller RT, Fletcher DL, Simonyl A, Rudeen PK. Chronic ethanol treatment reduces responsiveness of the hypothalamic-pituitary-thyroid axis to central stimulation. Alcoholism, Clinical and Experimental Research 1996 Aug;20(5):954-60 https://www.ncbi.nlm.nih.gov/pubmed/8865974/
[ix] Gershengorn MC. Bihormonal regulation of the thyrotrophin-releasing hormone receptor in mouse pituitary thyrotropic tumor cells in culture. Journal of Clinical Investigation 1978 Nov;62(5):937-43. Doi: 10.1172/JCI109222 https://www.ncbi.nlm.nih.gov/pubmed/213447/
[x] Sheppard MC, Shennan KI. Desensitization of rat anterior pituitary gland to thyrotrophin releasing hormone. Journal of Endocrinology 1984 Apr;101(1):101-5 https://www.ncbi.nlm.nih.gov/pubmed/6423761/
[xi] Effraimidis G, Tijssen JGP, Wiersinga WM. Alcohol Consumption as a Risk Factor for Autoimmune Thyroid Disease: A Prospective Study. European Thyroid Journal. 2012;1(2):99-104. doi:10.1159/000338920. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3821464/
[xii] Purohit V. Moderate alcohol consumption and estrogen levels in postmenopausal women: a review. Alcoholism, Clinical and Experimental Research 1998 Aug;22(5):994-7 https://www.ncbi.nlm.nih.gov/pubmed/9726268
[xiii] Santin AP, Furlanetto TW. Role of Estrogen in Thyroid Function and Growth Regulation. Journal of Thyroid Research. 2011;2011:875125. doi:10.4061/2011/875125. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3113168/
[xv] Baumgartner A, Rommelspacher H, Otto M, et al. Hypothalamic-pituitary-thyroid (HPT) axis in chronic alcoholism. I. HPT axis in chronic alcoholics during withdrawal and after 3 weeks of abstinence. Alcoholism, Clinical and Experimental Research 1994 Apr;18(2):284-94. https://www.ncbi.nlm.nih.gov/pubmed/8048729
[xvi] Liappas I, Piperi C, Malitas PN, et al. Interrelationship of hepatic function, thyroid activity, and mood status in alcohol-dependent individuals. In Vivo 2006 Mar-Apr;20(2):293-300. https://www.ncbi.nlm.nih.gov/pubmed/16634533/