Alcohol and Kidney Disease: How Can Alcohol Cause It?

About Kidney Disease

The kidneys are two fist-sized organs that filter the blood of toxins in order to create urine. They also filter water in order to keep the body hydrated and produce hormones. Kidney disease occurs when these two organs are not able to do their job, usually due to damage and toxic substances building up in the body. The primary risk factors for developing kidney disease are diabetes, high blood pressure, and heart disease. However, all of these factors are also influenced by alcohol intake, and alcohol’s impact on kidney function can cause long term damage. In the following sections we will examine more closely the relationship between alcohol intake and kidney disease and failure. 

Alcohol and Kidney Disease: Overview 

Since the kidneys are responsible for blood filtration, when alcohol enters the blood it naturally passes through the kidneys’ renal filtration system. Not only do kidneys have to work much harder in order to remove the harmful byproducts of alcohol consumption, but alcohol also encourages reduced fluid and electrolyte regulation within the body. This process is why many people feel the persistent need to use the bathroom while drinking. Ultimately, after heavy alcohol consumption the body is left dehydrated and with a hormonal imbalance. 

Some people claim they experience kidney pain after a night of drinking, however there is not much evidence to support this. Although heavy drinking does not appear to directly influence a person’s likelihood of developing kidney stones, being persistently dehydrated and drinking alcohol regularly may be a risk factor in their development.  Therefore, those who drink consistently without rehydrating may be influencing their likelihood of incurring the condition.  

Effects of Alcohol on Chronic Kidney Disease (CKD)

Chronic kidney disease (CKD) occurs when the kidneys are permanently damaged and can no longer effectively filter toxins from the blood, produce hormones, or regulate fluid levels. The primary contributors to CKD are type 2 diabetes, high blood pressure, and heart disease. All of these factors are influenced by alcohol consumption and can be managed through a healthy relationship with alcohol. 

First, diabetes is caused and perpetuated by persistently high blood sugar. Alcohol, especially sugary drinks like wine and cocktails, will raise blood sugar and contribute to the development of type 2 diabetes. In fact, type 2 diabetes is the leading cause of CKD, where high blood glucose levels damage kidney blood vessels over time, and impair their function. 

One of the first signs of kidney disease related to diabetes is protein in urine, called albuminuria, due to the kidneys no longer able to retain this essential component of nutrition. For those with diabetes, consuming a moderate amount of alcohol may be okay, so long as you have your blood sugar under control and your doctor or renal dietician has approved it. 

Excessive alcohol use may also lead to high blood pressure, although it is not clear why.¹ Having high blood pressure places a constant strain on the small blood vessels within the kidney, and ultimately causes damage if not controlled. Without the function of the small vessels, the kidney cannot filter out toxins and other harmful substances that build up in the bloodstream. Furthermore, alcohol can inhibit the effectiveness of high blood pressure medications, therefore allowing kidney damage to continue during episodes of binge drinking.  

Heart disease, much like diabetes and high blood pressure, is a leading contributor to kidney disease and can, in part, be caused by alcohol consumption. Alcohol, despite having no nutritional benefit, does contain a significant number of calories that can add up quickly. These calories can contribute to increased cholesterol levels within blood vessels, and therefore increase the risk of stroke, heart attack, or other cardiovascular disease-related events. Furthermore, the blood vessel hardening associated with heart disease limits kidney function and contributes to the development of CKD. 

Unfortunately many of these risk factors occur together, and alcohol abuse can contribute to all of them. Therefore, by limiting your alcohol intake you can help decrease the risk of diabetes, high blood pressure, heart disease, and therefore possible kidney disease as a result. 

Kidney Failure and Alcohol Consumption

Kidney failure, often referred to as end-stage renal disease (ESRD), is the final progression of CKD. Failure often occurs when kidney dysfunction has become so severe that the blood is no longer being effectively filtered, usually caused by long term damage to renal blood vessels. The leading causes of kidney failure are type 2 diabetes and high blood pressure. Both of these conditions are exacerbated by alcohol consumption, and directly injure small filtration blood vessels. The symptoms of renal failure include itching, nausea, muscle cramps, loss of appetite, swelling in your feet or ankles, and urine irregularities. 

Unfortunately, once CKD has reached ESRD, the only treatment option is a kidney transplant. However, life can be prolonged via dialysis before a transplant. Dialysis is a process that manually filters the blood of toxins in place of damaged kidneys. 

Sometimes kidneys can stop functioning suddenly, a condition often called acute kidney injury. These events are usually related to heart attacks, illicit drug use, or extremely limited blood flow. If treated urgently, the kidneys may return to normal function, and long-term damage can be avoided. In the case of a heart attack, alcohol abuse can significantly increase the risk of cardiovascular disease, and in turn the risk of this type of event. 

FAQs

How long does it take for kidneys to repair themselves?

Once CKD has reached a certain stage, the kidney would no longer be able to repair itself or function properly. However, early detection may allow for the issue causing kidney injury to be resolved, and renal function to return to normal. Detection of kidney disease usually involves a serum creatinine test, in order to measure the amount and types of waste products passing through the renal filtration system and into urine. The majority of interventions utilised to reverse kidney damage include lifestyle changes such as an improved diet, regular exercise, or other methods of treating type 2 diabetes or high blood pressure. If these treatments are well maintained, your kidneys may begin to heal themselves slowly, but it is more likely that their filtration burden will be reduced, as opposed to being completely healed.  

What drinks are hard on the kidneys?

Any type of sugary drink can increase your risk of diabetes or high blood pressure, and therefore your risk of kidney disease. The main drinks to avoid include sugary fizzy drinks or alcohol. Furthermore, caffeine can raise blood pressure and contribute to a strain on kidney function. Drinking caffeinated teas, coffees, and energy drinks may also increase your risk of developing kidney stones and should be enjoyed in moderation.

Does alcohol make kidney disease worse?

Alcohol can certainly exacerbate CKD and the conditions that lead to it. These include type 2 diabetes, high blood pressure, and heart disease. Furthermore, excessive alcohol consumption is a key contributor to liver disease. When damaged, the liver, also largely responsible for cleansing toxins from the body, will increase the filtration strain placed upon the kidneys. It is important to talk to your doctor about your drinking habits and whether or not they could be impacting your kidney function. 

Is kidney damage from alcohol reversible?

If damage is extensive, like that caused by type 2 diabetes or high blood pressure, it cannot be reversed. However, if caught and treated early, renal function may return to normal. If you are suffering from conditions that are exacerbated by alcohol consumption such as diabetes, high blood pressure, liver disease, or others, you may want to limit or cease alcohol consumption. The NHS recommends not drinking more than 14 units (one beer, one glass of wine, or one shot of liquor) of alcohol per week, and to spread consumption over at least three days. 

What is the best drink for kidneys?

The answer is simple: water! Water is a zero calorie, hydrating, and a cheap option. Keeping your body hydrated will help the kidney perform its function as well as keep your urine normal. There are several ways to increase water intake, but the most fun can be downloading a hydration tracker app or incentivising regular water consumption in a way that works for you.