Enquiries: 01305 251150

Updated 2 August 2023


Abstinence (not drinking alcohol at all) for three to eight weeks before surgery significantly reduces your risk of complications after surgery. 

  • men and women should not drink more than 14 units each week
  • if you drink more than 4 units a day you are 50% more likely to get a complication after your operation. 

Units of alcohol:

  • 25ml of spirits = 1 unit
  • Alcopop (275ml) = 1.5 units
  • Bottle of lager/beer/cider (330ml ABV 5%) = 1.7 units
  • Can of lager/beer/cider (440ml ABV 5.5%) = 2 units
  • Standard glass of wine (175ml ABV 12%) = 2.1 units
  • Large glass of wine (250ml ABV 12%) = 3 units
  • Pint of lower-strength lager/beer/cider (ABV 3.6%) = 2 units
  • Pint of higher-strength lager/beer/cider (ABV 5.2%) = 3 units

For further information or support, please contact our Addiction Specialist Nurse Debbie Cobb at deborah.cobb@dchft.nhs.uk


If you smoke, please use this time before your surgery as an opportunity to cut down or, even better, stop smoking completely. As well as making you healthier in the long run, this will really cut down your risks of having a complication after surgery.

Although it is best to quit at least eight weeks before surgery, there are still benefits from quitting even 24 to 48 hours before your operation.  

Did you know? 

  • after 8 hours – your blood oxygen levels return to normal
  • after 24 hours – carbon monoxide is eliminated from your body

Further information and support can be found on our Tobacco Dependency page or on the LiveWell Dorset website

People who are well nourished have the best outcomes from surgery. You can be malnourished whatever your weight.

Calculate your BMI 
BMI stands for body mass index and is a measure of whether you are a healthy weight for your height.

Click here to calculate your BMI.

If you are underweight, you should try and gain some weight or not lose any further weight before your surgery.

If you are overweight, losing some weight before surgery will reduce your chances of a complication.

Managing weight is hard. Changing your diet prior to a stressful event such as surgery is difficult but can make a real difference. Good quality, evidence-based advice gives you the best chance of success.

If your weight is something you would like to target, we recommend you take a look at the following resources: