New Series — What Your Surgeon Isn't Telling You
This series applies functional nutritional assessment to surgical and injury recovery — the gap between what conventional medicine does before and after an operation and what the biology of healing actually requires. Also covers sports injury, IVF, dental implants, and other procedures where nutritional status is a primary but overlooked determinant of outcome.
Surgery is a controlled wound. That is not a reductive description — it is a precise one. Whether it's a hip replacement, a knee arthroscopy, an ACL repair, a mastectomy, or a laparoscopic cholecystectomy, the fundamental biological event is the same: tissue is cut, blood vessels are disrupted, the inflammatory cascade is triggered, and the body mobilises its repair machinery to close, rebuild, and remodel.
The quality of that repair machinery is not fixed. It depends on what the body has available to work with — the nutritional substrate that determines how efficiently each phase of wound healing proceeds, how robustly the immune response is mounted, how effectively collagen is synthesised and remodelled, and how quickly and completely function is restored.
The NHS pre-operative assessment is thorough about what it covers. Cardiovascular fitness for anaesthetic. Medication review. Baseline bloods for organ function. Allergy history. Consent for the procedure. These are important and appropriate.
What is not covered — in the NHS or in most private surgical contexts — is the nutritional foundation on which the surgery will be performed. And that foundation varies enormously between individuals, in ways that are now well documented to affect surgical outcomes significantly.
The wound healing cascade — what it actually requires
Wound healing proceeds through four overlapping phases. Understanding them makes it immediately clear why nutritional status matters.
The Four Phases of Wound Healing — and Their Nutritional Dependencies
Phase 1
Haemostasis
(minutes–hours)
Blood vessel constriction, platelet aggregation, clot formation. Requires adequate vitamin K for clotting factor synthesis. Omega-3 fatty acids influence platelet aggregation — relevant for anyone taking fish oil pre-operatively (usually advised to stop 1–2 weeks pre-surgery). Zinc plays a role in platelet function.
Phase 2
Inflammation
(days 1–5)
Immune cells (neutrophils, macrophages) clear debris, pathogens, and damaged tissue. Requires adequate zinc for immune cell function, vitamin C for neutrophil activity, vitamin A for macrophage activation. Chronic pre-existing inflammation — elevated CRP, gut dysbiosis, high toxic burden — prolongs and dysregulates this phase, extending recovery and increasing complication risk.
Phase 3
Proliferation
(days 4–21)
Fibroblasts produce new collagen, blood vessels regenerate (angiogenesis), and the wound is covered with new epithelium. This is the most nutritionally demanding phase. Requires vitamin C (rate-limiting for prolyl hydroxylase — the enzyme that builds the collagen triple helix), zinc, copper, iron, glycine, proline, and adequate dietary protein. Deficiency in any of these slows or impairs the collagen output of this phase.
Phase 4
Remodelling
(weeks–months)
Immature collagen is cross-linked and remodelled into mature, organised scar tissue. Requires copper-dependent lysyl oxidase for cross-linking, ongoing vitamin C, zinc, and mechanical loading (which is why physiotherapy matters — the tissue remodels in response to the forces applied to it). This phase continues for up to two years in major procedures. Nutritional status during rehabilitation, not just immediately post-operatively, determines final functional outcome.
The nutrients that matter most — and how commonly they're deficient
Vitamin C
Rate-limiting for collagen synthesis
The enzyme prolyl hydroxylase — which builds the collagen triple helix — requires vitamin C as an obligate cofactor. Without adequate vitamin C, collagen cannot form its characteristic structure and is mechanically inadequate. Surgical wounds in vitamin C-insufficient individuals heal more slowly and are more prone to dehiscence (reopening).
UK population insufficiency is common, particularly in the elderly, smokers, and those with poor dietary variety. Stress and surgery dramatically increase requirements.
Zinc
Immune function and collagen remodelling
Required for immune cell proliferation during the inflammatory phase, for the matrix metalloproteinases that remodel collagen, and for epithelial regeneration. Zinc deficiency impairs all three phases of wound healing. It is the most consistently documented nutritional deficiency affecting surgical outcomes in peer-reviewed literature.
Extremely common in the UK — particularly in women eating low red meat diets, those with gut absorption issues, and those under chronic stress. Standard blood serum zinc is an insensitive marker of deficiency.
Vitamin D
Immune modulation and bone healing
Vitamin D receptors are present on virtually every immune cell. Deficiency impairs the innate immune response to surgical bacterial exposure and increases post-operative infection risk. For orthopaedic procedures specifically — hip and knee replacement, spinal surgery — vitamin D is essential for bone remodelling and implant osseointegration.
UK vitamin D insufficiency is endemic — particularly in Scotland where adequate sun exposure is limited to 4 months. The NHS threshold (50 nmol/L) is inadequate for optimal immune and bone function.
Iron / Ferritin
Oxygen delivery and collagen hydroxylation
Iron is required for haemoglobin — the oxygen carrier that delivers oxygen to healing tissue. Post-operative anaemia dramatically slows recovery and increases complication risk. Iron is also a cofactor for prolyl hydroxylase alongside vitamin C. Women of reproductive age are extremely likely to enter surgery with suboptimal ferritin.
NHS pre-operative assessment checks haemoglobin but not ferritin. A haemoglobin within normal range with ferritin of 12 µg/L represents significant iron insufficiency that will impair healing.
Protein / Amino Acids
The substrate for all repair
Collagen is protein. Immune cells are protein. Enzymes are protein. Every aspect of wound healing requires dietary protein as substrate. Protein requirements increase significantly post-operatively — up to 1.5–2g per kg body weight per day in major surgery. Many patients enter surgery already eating inadequate protein and are discharged on hospital food that compounds the deficit.
Particularly relevant for older patients, those on calorie-restricted diets, and vegetarians/vegans who may have adequate total protein but suboptimal amino acid profiles for collagen synthesis.
Vitamin A
Epithelialisation and immune activation
Vitamin A regulates the inflammatory phase — activating macrophages and supporting epithelial cell regeneration. Deficiency impairs the inflammatory phase and slows epithelialisation. It also modulates the immune response to surgical trauma, reducing the risk of dysregulated inflammation that drives post-operative complications.
Dietary preformed retinol comes from animal sources. Those following plant-based diets rely on beta-carotene conversion — which is genetically variable and frequently inadequate.
Omega-3 Fatty Acids
Inflammation resolution
Omega-3s are precursors to resolvins and protectins — the specialised pro-resolving mediators that actively terminate the inflammatory phase. Without adequate omega-3, the inflammation of wound healing resolves more slowly and less completely. Importantly, high-dose omega-3 should be stopped 1–2 weeks before surgery due to effects on platelet aggregation — then resumed post-operatively to support resolution.
UK dietary omega-3 intake is consistently below recommended levels. The omega-6:omega-3 ratio in the modern UK diet is approximately 15:1, against an optimal of 4:1 or lower.
Magnesium
Pain, muscle function, anaesthetic recovery
Magnesium modulates NMDA receptor activity — relevant for post-operative pain management. Low magnesium increases pain sensitivity, prolongs post-operative nausea, and impairs muscle recovery post-orthopaedic surgery. It is also depleted by surgical stress and by common hospital medications including proton pump inhibitors.
Chronically insufficient across the UK population. Hospital food is unlikely to restore it. Often not monitored post-operatively.
The inflammation problem
There is a dimension of surgical preparation that goes beyond individual nutrient status — the baseline inflammatory load that the patient brings into the operating theatre.
Chronic low-grade inflammation — the kind driven by gut dysbiosis, intestinal permeability, toxic burden, chronic stress, and poor diet — doesn't resolve when you go under anaesthetic. It persists into the post-operative period and interacts with the surgical inflammatory response in ways that complicate recovery.
The inflammatory phase of wound healing is necessary and appropriate. But when it is superimposed on an already-elevated inflammatory baseline, the result can be a dysregulated, prolonged inflammatory response — increased post-operative pain, slower healing, higher infection risk, and a proliferative phase that is compromised by the continued cytokine burden from chronic background inflammation.
Elevated CRP pre-operatively is an independent predictor of surgical complications and extended hospital stay. The NHS pre-operative assessment does not routinely check CRP. It would take 30 seconds and cost a few pounds to add it to the pre-operative panel — and it would identify patients whose inflammatory load warrants attention before, not after, the knife goes in.
Sports injury — the same biology, a different context
The nutritional dependencies of surgical wound healing apply equally to sports injury recovery — because the biology is the same. A torn ACL, a stress fracture, a rotator cuff tear, a muscle belly rupture — these are all tissue injuries that heal through the same four-phase cascade, with the same nutritional requirements, and the same individual variation in nutritional status that determines how well and how quickly that healing proceeds.
Ligament and tendon injuries (ACL, Achilles, rotator cuff)
Collagen-dependent repair
Ligaments and tendons are primarily collagen. Their repair is completely dependent on collagen synthesis — which requires vitamin C, zinc, glycine, proline, and iron in the adequate doses and forms discussed above. The vitamin C angle is particularly important here: collagen produced in vitamin C-insufficient conditions lacks the hydroxylation needed for proper triple helix formation and is mechanically inferior. The re-rupture risk of an incompletely mineralised ligament repair is real and clinically significant. Collagen peptide supplementation (10g daily alongside vitamin C) has emerging evidence specifically for tendon and ligament repair — the collagen peptides provide the amino acid substrate directly at the site of synthesis.
Stress fractures and bone injuries
Bone mineralisation and remodelling
Bone healing requires calcium, phosphorus, magnesium, vitamin D, vitamin K2, and silicon — alongside adequate protein for the collagen matrix on which mineralisation occurs. Vitamin D is the most critical and most commonly deficient. A stress fracture in a vitamin D-insufficient athlete is healing on a suboptimal substrate. K2 is required to activate osteocalcin — the protein that directs calcium into bone rather than soft tissue. The combination of D3 and K2 is clinically important, not just D3 alone.
Muscle injuries (strains, tears)
Satellite cell activation and protein synthesis
Muscle repair involves satellite cell activation — the muscle stem cells that proliferate and differentiate to replace damaged muscle fibre. This process is strongly anabolic and requires adequate dietary protein, leucine specifically (as the primary trigger for muscle protein synthesis via mTOR), creatine (which supports ATP availability for the energy-demanding repair process), and omega-3 fatty acids (which modulate the inflammatory phase and support satellite cell function). Magnesium is required for muscle relaxation and for the enzymatic processes of protein synthesis.
Cartilage damage and joint injuries
Limited intrinsic repair capacity — support is critical
Articular cartilage has limited blood supply and therefore limited intrinsic repair capacity. This is why cartilage injuries are so clinically challenging. Nutritional support cannot regenerate lost cartilage but it can slow further degradation and support the surrounding tissue. Glucosamine and chondroitin have a contested evidence base — the quality of evidence is variable. Collagen peptides, specifically type II collagen, have more consistent recent evidence for joint health. The inflammatory load is particularly relevant here — systemic inflammation drives cartilage-degrading matrix metalloproteinase activity. Reducing inflammatory burden is a primary intervention for joint health, not a secondary one.
The IVF parallel — and why this thinking applies more broadly
The pre-surgical optimisation argument applies beyond orthopaedics and sports injury. Any procedure that relies on the body's biological repair and regeneration capacity is enhanced by a nutritional foundation that supports that capacity.
IVF is a compelling example. A cycle costs upward of £5,000. The probability of success is substantially influenced by egg quality and uterine receptivity — both of which have documented nutritional dependencies. CoQ10 (mitochondrial energy production in the egg), methylfolate (MTHFR-appropriate folate for DNA methylation and neural tube formation), zinc and selenium (antioxidant protection of the developing embryo), vitamin D (uterine receptivity and implantation), omega-3 (endometrial blood flow) — these are specific, measurable, correctable nutritional factors that influence IVF outcomes and are not assessed by any fertility clinic.
Dental implants are another example. Osseointegration — the process by which a titanium implant fuses with surrounding bone — requires exactly the nutritional conditions for bone healing described above. Implant failure rates vary with vitamin D status, zinc status, and systemic inflammatory load. Nobody checks these before placing a £2,000 implant.
The pattern is consistent across every procedure that relies on the body's biological machinery to produce the outcome: the machinery is nutritionally dependent, individual variation in nutritional status is significant, and nobody is assessing it.
The surgeon's skill determines what is possible. The patient's nutritional status determines what is achieved. Only one of these is currently being optimised before an operation.
What a pre-surgical nutritional assessment looks like
An eight-week pre-operative nutritional optimisation period — for any elective procedure — would include:
Blood chemistry assessment — ferritin (not just haemoglobin), zinc, vitamin D, vitamin C (functional assessment where possible), CRP as an inflammatory marker, albumin as a protein status marker, full blood count. This takes one blood draw and costs a fraction of the procedure itself.
Dietary protein assessment — is the patient eating adequate protein to support the post-operative anabolic demand? For most adults, 1.2–1.5g per kg body weight is the target before surgery, rising to 1.5–2g per kg in the immediate post-operative period.
Inflammatory load assessment — CRP as a minimum. Where there is a history of gut symptoms, food reactivity, or chronic illness, a GI-MAP revealing the microbiome and permeability picture changes the picture significantly. A patient entering surgery with significant gut dysbiosis and intestinal permeability is entering with a systemic inflammatory burden that will complicate recovery.
Targeted supplementation in the pre-operative window — vitamin C (2–4g daily from 4 weeks before), zinc (25–30mg daily), vitamin D to optimise serum levels, collagen peptides with vitamin C for ligament/tendon procedures, adequate protein. Stop omega-3 1–2 weeks pre-operatively, resume post-operatively.
Post-operative continuation — nutritional support doesn't stop when you leave hospital. The remodelling phase continues for months. Zinc, vitamin C, protein, vitamin D, and omega-3 should be maintained throughout the rehabilitation period.
Why this isn't happening
The honest answer is structural. The NHS pre-operative pathway is designed for safety — anaesthetic safety, infection risk, cardiovascular risk. It was not designed to optimise outcomes, because outcome optimisation was historically considered the patient's responsibility and the physiotherapist's domain.
Private surgical providers have the flexibility to do this but rarely do — because there is no financial incentive to add a pre-operative nutritional assessment to a package that the patient has already paid for, and because the surgeon's role is defined by what happens in theatre, not by the nutritional preparation of the tissue they're operating on.
The result is that patients invest significant sums — £10,000–£20,000 for a private hip replacement, £5,000 per IVF cycle, £2,000+ per dental implant — on a biological foundation that nobody has assessed or optimised. The procedure is excellent. The preparation for it is incomplete.
That gap is exactly where functional nutritional assessment sits — and exactly where it can make a measurable difference to outcomes that matter to the person on the operating table.
Planning surgery or recovering from injury?
The DH Clinical Concierge can help you understand what nutritional optimisation would look like for your specific procedure or injury — no appointment needed.
Talk to the Concierge
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