Alcohol and its effect on diseases

Whenever you mention the health related effects of alcohol consumption most people immediately think of alcoholism. The caricature of the drunken tramp lying in the gutter comes to mind or even the vision of the aggressive lager-soaked football supporter. Others think of blood-spattered hooligans rampaging through the accident and emergency departments of our hospitals. Some may even conjure up the image of an uninhibited drunk urinating or vomiting in a doorway.

Ireland has a serious problem with the level of alcohol consumption in our society. There is an acknowledgement that our society would experience far fewer accidents, far fewer assault cases and less chaos in our hospitals if Irish people were more responsible in their drinking habits.

Diabetes and alcohol

But did you know that alcohol could have a detrimental effect on your health even if you were not an alcoholic? Maybe you know that alcohol can interact with a wide variety of prescription drugs, over the counter preparations and so-called 'natural' products. But did you know that alcohol could affect the course of a chronic health problem that afflicts you? As Michael Caine might say, 'not many people know that'.

Alcohol can affect such common conditions as diabetes, high blood pressure and high fat levels in the blood. This issue is important because many Irish people are being treated for these conditions without being aware that the level of alcohol they consume is having a direct impact on their condition. I am referring specifically to the interaction between alcohol and the condition and not an interaction between alcohol and the treatment being prescribed for treating that condition. Let me give you an example.

It has been demonstrated in the medical literature that people with diabetes who consume alcohol can have higher than normal blood glucose level or lower than normal blood glucose level depending on their nutritional status. Clearly this is of crucial importance since impairment of sugar regulation is central to the diabetic’s problem. Long-term alcohol consumption in a well-nourished diabetic can lead to chronically elevated glucose levels in the blood. The technical name for elevated blood glucose is hyperglycaemia. Conversely if a diabetic has not eaten for a while alcohol can cause the blood glucose level to drop further. Low blood glucose is referred to as hypoglycaemia. Both hyperglycaemia and hypoglycaemia can have damaging consequences for the diabetic.

Effects on the liver

Let us look a little more closely at what is happening in the liver of a fasting diabetic who drinks alcohol. The liver tries to counteract the falling level of glucose in a process known as gluconeogenesis, which literally means generating new sugar. This process requires that certain compounds be generated within the liver. However, alcohol metabolism in the liver has a direct negative impact on this chemical chain reaction thereby plunging the blood glucose levels to new depths. In other words alcohol directly counteracts the liver’s mechanisms for generating glucose.

One further concern regarding the diabetic is that mild alcohol intoxication may mimic the symptoms of a hypoglycaemic attack leading the person to assume that their symptoms are due to slight inebriation and not a potentially dangerous hypoglycaemic attack. The diabetic might misread the situation and consequently might take the wrong course of action

High blood pressure

I have gone on at some length about diabetes to illustrate the point that alcohol can affect metabolic processes in the body in a very fundamental way. However, let us take another example of a condition that is more widespread in society than diabetes. High blood pressure is very prevalent in Ireland and is a major risk factor for heart attack. We don’t yet know what levels of alcohol consumption cause high blood pressure but we do know that there is a link between the two.

The precise mechanisms at work are less clearly understood than the example of diabetes just given but it is a well-established fact that some people with high blood pressure may revert to normal levels of blood pressure if they stop drinking alcohol. This simple truth could be very significant for a lot of people. If you were found to have high blood pressure and enjoyed a few drinks on a regular basis would you not like to consider the choice of curtailing alcohol consumption rather than commencing a life long course of taking pills?

Let us take a further example of alcohol affecting a disease process and take a look at the topical subject of hepatitis C. It is well known that hepatitis C can cause liver damage that can progress on to cirrhosis and even liver cancer. Alcohol consumption can accelerate the progression of liver damage in sufferers of hepatitis C and can also render them less responsive to the beneficial effects of interferon. Specialists don’t yet fully understand why this happens but it is considered best for hepatitis C sufferers to abstain from alcohol consumption particularly during treatment with interferon.

Fat levels

Let us now turn to another health problem that is more endemic than hepatitis c. Let’s look at the effects of alcohol on fat levels in the blood. Alcohol can affect particular fats in the blood called triglycerides. These compounds are important in the development of cardiovascular disease, especially heart attack. Alcohol can elevate trigylceride levels in the blood by directly influencing the mechanisms that produce them in the liver. The mechanism is comparable to the effect of alcohol on glucose production in the liver of a diabetic. If you have been found to have high triglyceride levels in your blood it might be worthwhile abstaining from alcohol to establish if it is making a significant contribution to the high triglyceride levels in your blood.

I could proceed to generate an encyclopaedia-like list of conditions that are alcohol induced but I will resist the temptation. Let me simply underline the point that I have been making: you don’t have to be an alcoholic to suffer health consequences from drinking alcohol.

Next time you think about alcohol and health dispel the traditional caricatures from your mind. You could be drinking more alcohol than is good for you. Be moderate in your consumption.

Dr Leonard Condren is the medical editor of