Despite its widespread popularity, alcohol is a potent toxin that can have profoundly negative impacts on overall health and wellbeing. An estimated 15.1 million Americans (more than 6% of the adult population) meet the criteria for having an alcohol use disorder (AUD).
The data for teenagers is even more alarming: In 2018, 13% of Florida 12th graders reported at least one binge-drinking episode within the previous 30 days, and nearly 30% reported having at least one drink. The negative impact of alcohol on the liver is well-known, but whether a direct relationship between AUD and kidney damage exists remains an area of active investigation. What is known is that alcohol-induced damage to other organ systems (including the liver, the heart, the gastrointestinal tract, and even muscle tissue) can negatively affect kidney function.
The Role of the Kidneys
The kidneys are a key component of the excretory system and filter blood to remove excess water, metabolic byproducts, cellular debris, and toxins. In addition, the kidneys help to regulate blood pressure and hormone production. Healthy kidneys filter about 150 liters of blood every day; that means they filter all of the blood in your body about 30 times per day! Kidney disease is related to a chronic reduction in the filtration rate, which reduces the ability of the kidneys to remove waste from the bloodstream.
How Alcohol Impacts Kidneys
The primary metabolizer of alcohol is the liver, so it accumulates the majority of direct alcohol-induced damage. The liver can only metabolize about one drink every hour, so if you have two drinks in 30 minutes, your liver will spend the next two hours metabolizing alcohol at the expense of normal metabolic function. Since your kidneys are constantly filtering blood, they will be directly exposed to alcohol. Thus, it is possible (even probable) that the kidneys may sustain direct damage from excessive alcohol consumption. However, alcohol’s effect on the kidneys remains largely unclear.
Whether alcohol can directly damage the kidneys is controversial.
A great deal of evidence exists showing that moderate alcohol consumption may be protective against kidney disease (but not against liver disease, so any benefit that may be gained in the kidneys is, at best, negated as your liver is damaged). Further confusing the question of whether alcohol directly affects kidney function are studies that have seemingly incompatible results. For example, a 2009 study evaluated kidney function in men who had consumed three or more alcoholic drinks every day for at least five years.
Two measures of kidney function were used: Urinary concentration of a protein called albuminuria, which accumulates when someone has kidney failure; and “estimated glomerular filtration rate” (eGFR) which is a standard test used to measure kidney function. The men were found to have abnormally high levels of albuminuria, suggesting kidney failure. However, they had improved eGFR compared to non-drinking men of similar ages, suggesting that they had improved kidney function. Even the authors of this study didn’t know how to interpret their data and they issued a warning against using their findings as a green light to consume alcohol chronically.
The data indirectly linking alcohol consumption to kidney injury is far stronger. The relationship between the kidneys and other organ systems is bidirectional, and if one organ is compromised all the other organs will be affected. Thus, alcohol-induced liver damage will necessarily have a negative effect on the kidneys.
Chronic AUD forces the liver to constantly detoxify alcohol in the blood. Over time, hepatocytes (liver cells) are literally poisoned to death. As dead hepatocytes accumulate, they form scar tissue (“fibrosis”) in the liver, and neighboring cells issue alarm signals that cause inflammation and vasoconstriction (constriction of blood vessels). Chronic vasoconstriction raises blood pressure, which is conclusively linked to kidney disease. Over 90% of people who have 4 or more alcoholic drinks per day for a decade will develop early-stage liver disease.
Signs of Kidney Problems
A major sign of kidney problems is abnormal urination. If you feel like you need to urinate more frequently than normal or like you cannot fully empty your bladder, your kidneys may be suffering. Foamy or bloody urine is a clear indication of kidney injury. Other less obvious indications of kidney problems include chronic fatigue, insomnia, swollen feet and ankles, puffiness around your eyes, muscle cramping and dry, itchy skin. If you have any combination of these signs, contact your doctor right away to rule out a potentially serious health condition.
Can Alcohol Cause Kidney Stones in Teens?
A direct link between alcohol use and kidney stone formation has not been identified. However, the kidneys play a role in pH regulation and electrolyte balance. Excessive alcohol consumption has been shown to reduce urine pH, which can promote uric acid kidney stones. In addition, alcohol can affect electrolyte balance by causing dehydration. When kidneys are dehydrated, electrolytes can crystallize and form stones. Youth does not allow someone to avoid alcohol-related kidney stones, and teens can get stones just as quickly as an adult.
Does Alcohol Cause Kidney Disease?
Whether or not alcohol directly causes kidney disease is controversial. However, it is indisputable that alcohol-induced damage to other organ systems has a negative impact on kidney health. Liver and cardiovascular cells that are chronically exposed to alcohol release pro-inflammatory molecules and “oxidants” that are delivered to the kidneys. Accumulation of these molecules in the kidneys may contribute to kidney disease.
In addition, the link between alcohol and liver and cardiovascular diseases is very clear. Both liver and cardiovascular disease lead to high blood pressure, which is the second most common cause of kidney failure.
Preventing Alcohol-Related Kidney Problems
The most reliable way to prevent alcohol-induced kidney problems is to not drink alcohol. Moderate alcohol consumption is unlikely to cause substantial kidney damage, and some evidence indicates that it may be protective against kidney damage (although not liver damage). However, teenage alcohol use is associated with particular risks that far outweigh any potential upside to moderate alcohol consumption. The bottom line is that teenagers should not drink alcohol as a best practice.
Urologists like to use the idiom “Dilution is the solution to the pollution”, meaning that the best way to prevent kidney pollution is to increase your water (not alcohol, soda or energy drink!) intake. Water flushes out toxins and other products that accumulate in the kidneys, keeping them clean and healthy.
Addressing Alcohol Abuse
Teenagers are at particular risk for damage caused by AUD. Over 4,000 teens die every year from excessive alcohol consumption, and nearly 120,000 teenagers visit emergency departments every year for alcohol-related injuries. Making matters worse, the adolescent brain is particularly susceptible to alcohol-induced damage. Teens who drink are at risk for learning and memory impairments and have a higher risk of developing serious AUD or substance use disorders as adults. Alcohol abuse treatment for teens can profoundly influence their immediate and long-term health and wellbeing. In 2017, 13% of Florida teenagers reported binge drinking within the past 30 days, and nearly 30% reported having had at least one drink. These statistics underscore the need for teenage-specific alcohol rehab programs in Florida.
If you know a teenager who is facing an alcohol use disorder, seeking treatment might save their life. Next Generation Village provides evidence-based, comprehensive residential and outpatient treatment programs for 13 to 17-year-olds who are struggling with alcohol or substance use disorders. Contact us today to learn how we can help your teen regain control of his or her life.