Targeted Assessment · Pre-Surgical Optimisation
Prepare Your Biology
Before the Operating Table
The surgeon's skill determines what is possible. Your nutritional status determines what is achieved. Ferritin, zinc, vitamin C, vitamin D, protein and inflammation all matter for healing. Apart from a full blood count before major surgery, none of them is among NICE’s routine pre-operative tests.
6–8 weeksOptimisation window before surgery
Blood draw requiredVia Regenerus or Nordic Labs
Written reportWith protocol and supplement plan
Stephen DuncanFDN-P MSc BSc · working with people since 1988
Who this is for
Any elective procedure benefits from nutritional preparation
The wound healing cascade — the biological process by which your body repairs itself after any surgical intervention — has specific nutritional dependencies at every phase. Clotting needs vitamin K. The inflammatory phase requires vitamin C and zinc for immune cell function. The proliferative phase where collagen is laid down requires vitamin C, zinc, copper, iron, glycine, and adequate dietary protein. The remodelling phase requires ongoing nutritional support for months after the procedure.
Most of this isn’t part of routine pre-operative testing: NICE recommends a full blood count before major surgery, but not iron stores, vitamin D, zinc, vitamin C or CRP (NICE NG45). You usually receive a cardiovascular fitness assessment, medication review, and consent for the procedure. What you don't receive is a nutritional assessment of the biological substrate on which the surgery will be performed.
What we assess
The markers the pre-operative pathway misses
Ferritin (not just haemoglobin)
Iron is required for prolyl hydroxylase — the enzyme that builds the collagen triple helix — alongside vitamin C. That’s laboratory biochemistry; how much low iron stores slow healing in people isn’t well measured.
Low iron stores can be missed when the full blood count looks fine. In anaemic patients, a ferritin of 30 µg/L (30 ng/mL) or less picked out iron deficiency far more reliably than the old cut-off of 12 µg/L (12 ng/mL) (Mast 1998). The British Society of Gastroenterology reads a ferritin below 30 µg/L (30 ng/mL) as low iron stores (BSG 2021).
Zinc
Required for immune cell function in the inflammatory phase, for matrix metalloproteinases in collagen remodelling, and for epithelial regeneration. Severe deficiency impairs healing; whether extra zinc helps people who aren’t deficient isn’t established.
Measuring zinc in one person is hard: plasma zinc changes with meals, time of day and inflammation, and falls during illness, so a good diet history often tells you more (King 2016).
Vitamin C
Rate-limiting cofactor for prolyl hydroxylase. Without adequate vitamin C, collagen cannot form its characteristic triple helix structure. Severe deficiency (scurvy) stops wounds healing properly. Whether extra vitamin C speeds surgical healing in people who aren’t deficient hasn’t been shown.
Blood levels fall sharply after major joint surgery: from about 49 to 12 µmol/L (0.86 to 0.21 mg/dL) a week after knee replacement. In that trial, vitamin C prevented the fall, but movement at a year was no better (Behrend 2019). Part of the fall is inflammation moving vitamin C around, so a blood level after surgery is hard to read (Conway 2015).
Vitamin D
Regulates osteoblast activity (bone healing), modulates the immune response to surgical bacterial exposure, and modulates the immune response. In observational studies, low vitamin D before surgery went with more surgical-site infections (the link was clearest below 30 ng/mL, 75 nmol/L) and more problems after shoulder surgery. Whether taking vitamin D before an operation prevents infections hasn’t been tested in trials.
Low winter levels are common in Scotland. UK deficiency cut-off: 25 nmol/L (10 ng/mL) (
SACN 2016). My working range: 75–125 nmol/L (30–50 ng/mL), a clinical target, not official guidance.
CRP (Inflammatory Load)
In a review of 52 studies (121,849 people having non-cardiac surgery), a higher CRP before the operation went with higher death rates afterwards, and in two of the studies with more major heart complications (Baskaran 2024). That’s observational: it doesn’t show that lowering CRP first changes the outcome.
Not among NICE’s routine pre-operative tests.
Protein Adequacy
Collagen, immune cells, and all repair enzymes are protein. Europe’s clinical nutrition society (ESPEN) treats malnutrition and underfeeding as risk factors for complications, and says nutrition support is needed for any surgical patient at nutritional risk (Weimann 2025).
Particularly relevant in older patients, those on calorie-restricted diets, and plant-based eaters.
What's included
Blood chemistry panel — ferritin, zinc, vitamin C functional markers, vitamin D, CRP, albumin (protein status), full blood count
Dietary protein assessment — adequacy for peri-operative demands
Inflammatory load assessment — CRP plus gut health indicators where relevant
Written clinical interpretation report
Targeted supplement protocol for the 6–8 week pre-operative window
Post-operative nutritional support plan continuing through rehabilitation
What you'll know
Whether your nutritional status is adequate for optimal surgical healing
Specific deficiencies that could impair your recovery if uncorrected
Your inflammatory baseline and whether it needs addressing before surgery
Exactly what to take, when, and at what dose in the weeks before your procedure
How to support the remodelling phase through rehabilitation
Timing
Book at least 8 weeks before your procedure date to allow time for blood draw, results, protocol implementation, and meaningful nutritional correction before surgery. If something needs correcting, allow time for a retest before surgery.
For sports injuries already sustained, the same assessment applies to rehabilitation — the wound healing biology is identical regardless of whether the injury is surgical or traumatic.
Sources
- Baskaran G et al. Associations of inflammatory biomarkers with morbidity and mortality after noncardiac surgery: a systematic review and meta-analysis. J Clin Anesth 2024;97:111540. PMID 38959697. doi:10.1016/j.jclinane.2024.111540
- Behrend H et al. Vitamin C demand is increased after total knee arthroplasty: a double-blind placebo-controlled randomized study. Knee Surg Sports Traumatol Arthrosc 2019;27:1182–8. PMID 29955932. doi:10.1007/s00167-018-5030-3
- Conway FJS et al. The relationship between acute changes in the systemic inflammatory response and plasma ascorbic acid, alpha-tocopherol and lipid peroxidation after elective hip arthroplasty. Clin Nutr 2015;34:642–6. PMID 25048713. doi:10.1016/j.clnu.2014.07.004
- Farsakoury R et al. Vitamin D deficiency and risk of surgical site infections: a systematic review and meta-analysis. Surg Infect 2026;27:78–84. PMID 41108122. doi:10.1177/10962964251389152
- King JC et al. Biomarkers of Nutrition for Development (BOND): zinc review. J Nutr 2016;146:858S–885S (online 2015). PMID 26962190. doi:10.3945/jn.115.220079
- Snook J et al. British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults. Gut 2021;70(11):2030–51. PMID 34497146. doi:10.1136/gutjnl-2021-325210. Below 15 µg/L: absent iron stores; below 30 µg/L: low iron stores; up to 100 µg/L can still mean iron deficiency in active inflammatory bowel disease.
- Mast AE et al. Clinical utility of the soluble transferrin receptor and comparison with serum ferritin in several populations. Clin Chem 1998;44:45–51. PMID 9550557
- NICE. Routine preoperative tests for elective surgery (NG45). nice.org.uk, read 14 October 2026.
- Papadopoulos DV et al. Association between vitamin D deficiency and adverse events following shoulder surgeries: a systematic review and meta-analysis. Indian J Orthop 2025;59:1255–64. PMID 40852540. doi:10.1007/s43465-025-01424-3
- Salman D et al. Does micronutrient supplementation improve outcomes in adult gastrointestinal surgery patients? A systematic review. Front Nutr 2025;12:1719617. PMID 41459083. doi:10.3389/fnut.2025.1719617
- SACN. Vitamin D and health. 2016.
- Weimann A et al. ESPEN guideline on clinical nutrition in surgery: update 2025. Clin Nutr 2025;53:222–61. PMID 40957230. doi:10.1016/j.clnu.2025.08.029
Trials of vitamins and minerals around surgery are few: a 2025 review of gastrointestinal surgery found too few to draw strong conclusions (Salman 2025).
Further reading
The clinical evidence behind this service
Not sure if you need this?
Talk to the Clinical Concierge first
Describe your procedure and current health picture — the concierge can help clarify what assessment would be most useful and whether the timing works.