I remember the first time I prepared for a scheduled operation: torn between wanting to control what I could and feeling overwhelmed by all the “do’s and don’ts.” Over the years I’ve worked with clinicians and sifted through the evidence, and one thing kept standing out—what you eat (and when) in the 24 hours before surgery can meaningfully affect complication risk and how quickly you recover. Below I share a practical, hospital-friendly plan you can adapt to your procedure, your tastes and any restrictions your surgical team gives you.
Why preoperative nutrition matters
Surgery causes stress the moment anaesthesia starts. Your body mounts an inflammatory response, breaks down glycogen and muscle, and becomes temporarily less efficient at handling glucose and fluids. That makes you more vulnerable to infection, delayed wound healing and longer hospital stays.
Good preoperative nutrition does three useful things:
Check with your team first
Before changing your routine, confirm with your surgeon, anaesthetist or pre-op nurse. Some procedures (e.g., bowel surgery, specific endoscopies) or medical situations (gastroparesis, delayed gastric emptying) require stricter fasting. What follows is a general, evidence-aligned plan that most elective-surgery patients can discuss and adapt with their care team.
Core principles for the “pre-op nutrition day”
A practical timeline you can follow (adapt with medical advice)
Below is a sample schedule for the 24 hours before surgery for an adult having elective surgery with standard fasting rules (no solids 6–8 hours prior, clear fluids allowed up to 2 hours prior). Adjust times to match your surgery slot.
| Time window | What to eat/drink | Why |
|---|---|---|
| 24 hours before | | Top up glycogen stores and keep GI tract settled. |
| Evening before | | Lower fibre and simple digestion help overnight comfort and reduce residue in gut. |
| Bedtime | | Prevents overnight dehydration without overloading stomach. |
| Morning of surgery (if allowed) | | Carbohydrate drink reduces insulin resistance and can decrease nausea and malaise post-op. |
What counts as a “clear carbohydrate drink”?
Hospitals often use special preoperative carbohydrate drinks (e.g., Nutricia PreOp or Ensure Pre-surgery formulations). If those aren’t available, acceptable alternatives include:
Note: these are intended for people without diabetes or with well-controlled diabetes—if you have diabetes you must follow specific guidance from your diabetes team.
Protein strategy in the pre-op day
Protein in the 24 hours before surgery helps preserve lean mass and gives your body building blocks for healing. Keep servings modest and choose easy-to-digest sources:
Aim for a combined 20–30 g of protein across your last full meals (e.g., 100–150 g skinless chicken + yoghurt snack). Avoid heavy, fatty cuts that slow gastric emptying.
Hydration specifics
Hydration is deceptively important. Dehydration increases risk of orthostatic hypotension and affects drug metabolism. That said, guidelines for clear fluid fasting are strict close to surgery.
Medications and supplements — what to tell your team
Bring a list of medications and supplements to pre-op. Some supplements alter bleeding risk (e.g., fish oil, ginkgo, high-dose vitamin E), and herbal remedies can affect anaesthesia. Common considerations:
Food examples you can rely on
Here are simple, hospital-friendly meals that follow the above rules. These are easy to prepare and tend to be stomach-friendly:
Practical tips and small hacks
I’ve seen first-hand how small, consistent steps before surgery make a difference: patients who follow a clear pre-op nutrition plan often report less fatigue, quicker return of appetite and fewer early complications. Talk with your surgical team, adopt the principles above that work for you, and give your body the best possible start for recovery.
