"Recent reports have shown that people are unaware of calories in drinks and don't include them when calculating their daily consumption. This is important from a cancer perspective because, after smoking, being overweight or obese is the biggest risk factor."

Alcohol is second only to fat in the number of calories per gram. Karen Chong, a registered dietitian with Matilda International Hospital, explains: "In our diet, there are four things that we get calories from: carbohydrate, protein, fat and alcohol. For one gram of each of those, carbohydrate and protein give us four calories, alcohol gives us seven and fat gives us nine."

There may be two reasons why calories are often overlooked when it comes to alcohol, says Dr Goh Ping Ping, a cardiologist at the Cardiac Specialist Centre of Mouth Elizabeth Medical Centre in Singapore.

"Although we know the calorie content of alcohol, the actual calories consumed from a drink depends on its alcohol percentage," she says. "There are many types of alcoholic beverage, each with a different alcohol content from very high, such as in spirits, to lower, such as in beer. Hence it may be difficult to tell how many calories are being consumed.

"Secondly, alcohol is usually not regarded as a 'sweet' beverage. People tend to worry more about the calories in soft drinks or ice cream because of the sweetness."

The higher a drink's alcohol content, the more calories it contains. So whisky or vodka have more calories per millilitre than wine which has more than beer. "However, there is no best or worst alcoholic drink as people tend to consume a much larger volume of beer than whisky," Goh says. "Thus overall, the total calories consumed may be quite similar."

"Excess calories are converted to fats especially around the abdominal area and this type of weight gain increases the risk of developing diabetes, high cholesterol and hypertension."

Often, it's not just the alcohol that contributes to a person's calorie count. The food that can accompany drinks, and the mixers, can also be high in calories. Cocktails, for example, can contain high-calorie ingredients such as cream or chocolate syrup. It is also common for fried food or other unhealthy snacks to be eaten while drinking.

But there are healthier choices. "Nuts are good for the heart, but you need to choose the unsalted ones as too much salt can cause hypertension," advises Goh. "Fried foods in should also be consumed in moderation. Avoid snacks that contain trans fats and choose those low in saturated fat by looking at the food labels."

As for mixers, Chong suggests diluting your drink with a low-calorie mixer such as tonic water, or adding sugar-free or low-calorie soft drinks, or even some fresh fruit juice.

Chong suggests alternating between an alcoholic drink and water, which also helps you rehydrate; reducing the amount of calories you consume in your meals on days you know you're going to have alcohol; and drinking light beer or wine.

Goh advises caution even with light or low-calorie options as "the danger is over-consumption in terms of drinking a larger volume."

Most drinkers we spoke to were unaware of how many calories were in alcohol; some vowed to pay more attention. Emilie Gomez, 35, says she'll be sticking to wine from now on and Jason Chan, 38, says: "I might be diluting my drinks with healthier options now."