Eamonn Brady MPSI writes about nutrition, the often-overlooked cornerstone of wound management
Part 1: Relationship between nutrition and wound healing
Wound healing is a complex biological process that requires a co-ordinated interaction between multiple body systems. While wound management often focuses on dressings, infection control, and pressure redistribution, the importance
of nutrition is frequently underestimated. Adequate nutritional status is fundamental to every stage of wound repair, influencing tissue regeneration, immune function, collagen synthesis, and resistance to infection. Without sufficient nutrients and energy, even the most advanced wound care interventions may fail to achieve optimal outcomes.
Community pharmacists are increasingly involved in the management of patients with chronic wounds,
including diabetic foot ulcers, venous leg ulcers, pressure ulcers, and surgical wounds. As highly accessible healthcare professionals, pharmacists are well placed to identify nutritional risk factors that may be delaying healing and to provide evidence-based advice or referral when appropriate. Given the ageing population and rising prevalence of chronic disease, the importance of nutritional optimisation in wound management is likely to continue increasing.
The wound healing process
Wound healing occurs through a series of overlapping stages that restore tissue integrity following injury. Although these stages are often described separately, they function as a continuous and highly co-ordinated process.
Haemostasis represents the body’s immediate response to injury. Blood vessels constrict and platelets aggregate to form a clot, limiting blood loss while also creating a temporary framework for healing. The inflammatory phase follows, with immune cells removing bacteria and damaged tissue while co-ordinating repair. During proliferation, collagen is produced, blood vessels form, and new skin develops.
Finally, remodeling strengthens the repaired tissue over many months.
Why nutrition matters
Each stage of wound healing requires substantial metabolic resources. Tissue repair is an energy-intensive process and nutrient demands often increase significantly following injury. Patients with wounds may require higher levels of protein, calories, vitamins, minerals, and fluids than healthy individuals.
Protein provides the amino acids necessary for tissue repair and collagen synthesis. Vitamins and minerals support enzymatic reactions, immune responses, and cellular growth. Adequate hydration ensures nutrients and oxygen can be delivered efficiently to healing tissues. When nutritional intake is inadequate, healing may slow considerably, even when local wound care is appropriate.
Malnutrition and wound healing
Malnutrition remains a significant yet frequently under-recognised problem in healthcare settings. It is particularly common among older adults, nursing home residents, patients with chronic disease, and those recovering from major illness or surgery. Importantly, malnutrition is not limited to underweight individuals. Patients with obesity may also have significant protein, vitamin, or mineral deficiencies that adversely affect healing.
Patients who are malnourished often experience delayed wound closure, reduced collagen synthesis, impaired immune function, increased susceptibility to infection, greater risk of wound breakdown, longer hospital stays, and increased healthcare costs.
The pharmacist’s role in recognising nutritional risk Pharmacy teams frequently encounter patients with wounds during routine dispensing, medicines reviews, and chronic disease consultations. Warning signs such as unintentional weight loss, poor appetite, frailty, recurrent infection, or slow-healing wounds should prompt consideration of nutritional risk.
Simple questions regarding dietary intake, recent weight change, and fluid consumption can provide valuable information. Early referral to a GP, dietitian, or tissue viability service may help identify nutritional deficiencies before they significantly impair healing.
Part 2: Protein, energy requirements, and hydration in wound healing
Increased metabolic demands during wound healing
The development of a wound initiates a cascade of physiological processes that place significant metabolic demands on the body. Healing requires the synthesis of new tissue, the production of immune cells, the formation of blood vessels, and the manufacture of structural proteins, all of which require substantial amounts of energy and nutrients. As a result, patients with acute or chronic wounds often have nutritional requirements that exceed those of healthy individuals.
The degree of increased nutritional demand depends on factors such as wound size, depth, duration, infection status, and underlying medical conditions. Patients with extensive burns, pressure ulcers, diabetic foot ulcers, or multiple wounds may have particularly high nutritional requirements.
The vital role of protein in tissue repair
Protein is widely regarded as the most important macronutrient in wound healing. It provides the amino acids required for collagen production, connective tissue formation, immune mediators, enzymes, and new skin cells. Inadequate protein intake can impair collagen synthesis, reduce wound tensile strength and prolong healing times. Protein also supports immune function. Antibodies, cytokines, and many immune cells are protein-based structures. Patients with protein deficiency may therefore
be more susceptible to wound infection, which in turn will further delay healing.
Energy requirements and wound healing
Wound healing is an energy-dependent process, and insufficient calorie consumption may result in dietary protein being used as a source of energy rather than for tissue repair. Carbohydrates provide a readily available source of fuel for cellular activity and support immune function, while dietary fats contribute to cell membrane formation, hormone production, and absorption of fat- soluble vitamins.
ESPEN recommendations for wound healing
The European Society for Clinical Nutrition and Metabolism (ESPEN) provides practical guidance for patients with wounds, particularly those at risk of malnutrition or pressure ulcers. ESPEN recommends that many patients may require approximately 30-35kcal/kg/ day and 1.25-1.5g protein/kg/day to support wound healing and maintain lean body mass. Requirements should be individualised according to age, comorbidities, nutritional status, and wound severity.
ESPEN also emphasises the importance of adequate hydration and highlights the potential role of specialised oral nutritional supplements enriched with arginine, zinc, and antioxidants in selected patients with pressure ulcers or nutritional risk. These practical recommendations provide useful targets for healthcare professionals involved in wound management.
Hydration and tissue perfusion
Hydration is another frequently overlooked component of wound management. Water is essential for nutrient transport, waste removal, temperature regulation, and cellular function. Adequate hydration supports tissue perfusion, which refers to the delivery of oxygen and nutrients to tissues through the bloodstream. Poor hydration may impair circulation and limit the supply of nutrients required for wound repair.
Practical considerations for pharmacists
Community pharmacists frequently encounter patients at risk of inadequate nutritional intake. Older adults, nursing home residents, patients recovering from surgery, and those with chronic disease may struggle to meet increased nutritional requirements. Questions about appetite, weight loss, dietary intake, and fluid consumption can help identify barriers to healing. Where concerns are identified, pharmacists can recommend dietary measures, support the appropriate use of oral nutritional supplements, and facilitate referral for further assessment when required.
Part 3: Vitamins, minerals, and micronutrients involved in wound repair
Micronutrients and wound healing
While adequate protein, calories, and hydration provide the foundation for wound healing, a range of vitamins and minerals are also essential for optimal tissue repair. These micronutrients support collagen formation, immune function, oxygen transport, cellular growth, and protection against oxidative stress. Deficiencies can contribute to delayed healing, increased infection risk, and poorer clinical outcomes, particularly in older adults and those with chronic wounds.
Vitamin C and collagen synthesis
Vitamin C plays a significant role in collagen production, making it one of the most important micronutrients involved in wound repair. Collagen provides strength and structure to newly-formed tissue and supports wound closure. Vitamin C is also a powerful antioxidant, helping to protect cells from damage caused by inflammation and free radicals. Deficiency may result in impaired collagen formation, fragile tissues, and delayed healing. Good dietary sources include citrus fruits, berries, peppers, tomatoes, and green vegetables.
Vitamin A and epithelialisation
Vitamin A contributes to epithelialisation, the process by which new skin cells migrate across the wound surface. It also supports immune function and helps regulate inflammation. Inadequate vitamin A status may impair wound closure and reduce resistance to infection. Rich sources include liver, dairy products, eggs, and orange-coloured vegetables such as carrots and sweet potatoes.
Vitamin D and immune health
Vitamin D is increasingly recognised as an important contributor to wound healing. Beyond its role in bone health, vitamin D influences immune responses and inflammatory pathways. Low vitamin D levels have been associated with slower healing in some patient groups, particularly those with diabetic foot ulcers and chronic wounds. Pharmacists should remain alert to vitamin D deficiency in older adults, housebound patients, and nursing home residents.
Zinc and tissue repair
Zinc is involved in numerous enzymatic reactions required for cell growth, protein synthesis, and wound repair. It supports immune function and contributes to collagen formation. Zinc deficiency can result in poor wound healing and impaired resistance to infection. However, routine supplementation is generally not recommended unless deficiency is suspected or confirmed, as excessive zinc intake may interfere with the absorption of other minerals.
Iron and oxygen delivery
Iron is essential for the production of haemoglobin, the protein responsible for transporting oxygen throughout the body. Oxygen is critical for cellular metabolism, collagen synthesis, and immune defence within healing tissues. Iron deficiency anaemia may therefore contribute to delayed wound healing by reducing oxygen delivery to damaged tissue.
Supplementation and clinical practice
Although deficiencies in key micronutrients can adversely affect wound healing, supplementation should not automatically be recommended for all patients. The greatest benefit is generally seen in those with poor dietary intake, confirmed deficiency, malnutrition, or increased nutritional requirements.
Part 4: Impact of chronic diseases, nutritional barriers and medicines to wound healing
The impact of chronic disease on wound healing
Many patients with chronic wounds have underlying medical conditions that directly or indirectly impair healing. Even when nutritional intake appears adequate, diseases such as diabetes, peripheral vascular disease, and chronic kidney disease can affect nutrient utilisation, circulation, immune function, and tissue repair. Understanding these barriers is essential when assessing patients with delayed healing. Chronic disease often creates a cycle whereby poor healing increases metabolic demands, while the underlying condition simultaneously reduces the body’s ability to respond effectively.
Diabetes and wound repair
Diabetes is one of the most significant risk factors for poor wound healing. Persistently elevated blood glucose levels can impair immune function, reduce collagen production, and damage blood vessels. This limits oxygen and nutrient delivery to tissues and increases susceptibility to infection. Diabetic foot ulcers remain one of the most common chronic wound presentations encountered in practice.
Real-world example: An individual with poorly controlled type 2 diabetes develops a plantar foot ulcer. Despite regular dressing changes, healing remains slow because hyperglycaemia, peripheral neuropathy, and inadequate protein intake are all contributing to delayed tissue repair. Improved glycaemic control and nutritional optimisation can significantly improve outcomes.
Obesity and hidden malnutrition
Although obesity is often associated with excess calorie intake, many individuals with obesity have deficiencies in essential vitamins, minerals, and protein. This phenomenon is sometimes referred to as hidden malnutrition. Excess adipose tissue may also contribute to chronic low-grade inflammation, which can interfere with normal healing processes. Pharmacists should therefore avoid assuming that a patient with obesity is nutritionally replete simply because they appear well nourished.
Peripheral vascular disease and tissue perfusion
Peripheral vascular disease occurs when narrowed arteries reduce blood flow to the limbs. Reduced circulation limits the delivery of oxygen, nutrients, and immune cells to damaged tissue, increasing
the risk of delayed healing and wound breakdown. Nutritional interventions alone cannot overcome severe vascular insufficiency, but optimising nutritional status may help support healing alongside medical management.
Real-world example: A 76-year-old patient with peripheral vascular disease presents with a non-healing lower leg ulcer. Despite appropriate wound dressings, healing remains poor because arterial blood flow is inadequate. Nutritional support may assist healing, but vascular assessment and treatment remain essential.
Ageing, frailty, and reduced nutritional intake
Older adults represent a substantial proportion of patients with chronic wounds. Ageing is often accompanied by reduced appetite, changes in taste and smell, difficulties with chewing or swallowing, social isolation, and multiple long-term medical conditions. Frailty may further increase nutritional vulnerability. These factors frequently contribute
to inadequate intake of protein and micronutrients required for tissue repair.
Real-world example: An 84-year- old nursing home resident develops a pressure ulcer after a prolonged hospital admission. A review identifies poor appetite, recent weight loss, and reduced protein intake. Nutritional intervention alongside pressure- relieving measures becomes a key component of management.
Medication-related nutritional concern
Certain medicines can impair wound healing directly through effects on tissue repair or indirectly through effects on appetite, nutrient absorption, immune function, and nutritional status. As many patients with chronic wounds are older adults receiving multiple medicines, medication-related factors are often overlooked contributors to delayed healing.
Long-term corticosteroid therapy is one of the best-recognised medication-related causes of impaired wound healing. Medicines such as prednisolone, dexamethasone, and methylprednisolone can reduce collagen synthesis, suppress inflammatory responses required for tissue repair, and increase protein breakdown. Prolonged use may also contribute to muscle wasting, skin- thinning, impaired glucose control, and increased susceptibility to infection.
Real-world example: A patient receiving long-term prednisolone for polymyalgia rheumatica develops a lower leg ulcer that remains slow to heal despite appropriate dressings. Review of their medicines identifies chronic corticosteroid exposure as a potential contributor to delayed tissue repair.
Immunosuppressive medicines may also impair healing. Agents such as methotrexate, azathioprine, ciclosporin, tacrolimus, and mycophenolate suppress immune function and cellular proliferation, both of which are important during wound repair. Biologic therapies
Wound care used in rheumatoid arthritis, psoriasis, and inflammatory bowel disease may similarly influence inflammatory pathways involved in healing.
Cancer treatments can present additional challenges. Traditional chemotherapy agents target rapidly dividing cells and may impair new tissue formation. Some targeted therapies ? particularly VEGF inhibitors such as bevacizumab ? may interfere with angiogenesis (new blood vessel formation), reducing oxygen and nutrient delivery to healing tissue.
Several commonly-used medicines can contribute to nutritional deficiencies that may indirectly impair wound healing. Metformin, widely prescribed for type
2 diabetes, has been associated with vitamin B12 deficiency during long-term use. Vitamin B12 is important for cell division, nerve function, and red blood cell production, and deficiency may contribute to anaemia, neuropathy, and impaired tissue repair.
Real-world example: An older adult with type 2 diabetes and a chronic foot ulcer reports worsening fatigue and neuropathy. During a medication review it emerges that they have been taking metformin for more than 10 years. Subsequent testing confirms vitamin B12 deficiency, highlighting the importance of considering medicine- related nutritional factors when wounds fail to heal as expected.
Proton pump inhibitors (PPIs), including omeprazole, esomeprazole, and lansoprazole, may impair absorption of vitamin B12, magnesium, calcium, and iron during long-term use. Deficiencies may become clinically relevant in frail older adults and those with poor dietary intake.
Other medicines that may influence nutritional status include loop diuretics, which can contribute to zinc and magnesium losses; cholestyramine, which may reduce absorption of fat- soluble vitamins; and orlistat, which can decrease absorption of vitamins A, D, E, and K. These nutrients play important roles in immune function, skin integrity, and tissue repair.
Some medicines may also affect wound healing indirectly by reducing appetite or causing gastrointestinal side-effects. Opioids, certain antidepressants, digoxin, and some antibiotics may contribute to nausea, altered taste or reduced food intake, potentially leading to inadequate protein and calorie consumption.
Practical implications for pharmacists
Pharmacists frequently encounter patients with chronic diseases that place them at increased risk of delayed wound healing. Reviewing medicines, identifying weight loss, assessing dietary intake, and recognising nutritional risk factors can all contribute to earlier intervention. Medication review is particularly important, as certain medicines may impair wound healing directly or indirectly through effects on collagen synthesis, immune function, blood glucose control, appetite, or nutrient absorption. Pharmacists should therefore consider whether a patient’s current medication regimen could be contributing to delayed healing.
Referral to a GP, dietitian, tissue viability nurse, or vascular service may be appropriate, depending on the underlying cause. A holistic approach that addresses not only the wound itself, but also nutritional status, underlying medical conditions, and potential medication- related barriers to healing, is more likely to achieve successful outcomes.
Part 5: Nutritional assessment and interventions in clinical practice
Recognising nutritional risk in patients with wounds
Effective wound management requires more than treating the wound itself. Identifying patients who may be nutritionally compromised is a key component of care. Individuals with chronic wounds, recurrent infections, recent weight loss, poor appetite, or prolonged illness should be considered at increased risk of malnutrition. Early identification allows intervention before nutritional deficiencies significantly impair healing.
Nutritional screening tools
NICE recommends nutritional screening using a validated tool — eg, the Malnutrition Universal Screening
Tool (MUST) — in patients at risk of malnutrition. This tool incorporates body mass index, recent unintentional weight loss, and the effect of acute illness on nutritional intake. Although formal screening may not occur in every pharmacy setting, familiarity with these tools can help pharmacists recognise when referral is appropriate.
Food-first approaches
In many cases, improving nutritional intake begins with practical dietary advice. A food-first approach aims
to increase calorie and protein intake using ordinary foods before considering specialised nutritional supplements. Strategies may include encouraging more frequent meals, adding energy-dense ingredients to foods, increasing protein- rich snacks, and addressing barriers such as poor dentition or reduced appetite.
Oral nutritional supplements
NICE recommends oral nutritional support when dietary intake alone is insufficient to meet nutritional requirements. These products can provide additional calories, protein, vitamins, and minerals in a convenient format. Selection should be individualised according to patient needs, preferences, and underlying medical conditions.
When to involve other healthcare professionals Wound healing often benefits from a multidisciplinary approach. Dietitians can provide comprehensive nutritional assessment and tailored dietary plans, while tissue viability nurses, practice nurses, and medical practitioners contribute expertise in wound management and treatment of underlying disease. Timely referral is particularly important when wounds fail to progress despite appropriate care.
Opportunities within community pharmacy Community pharmacists are uniquely positioned to identify nutritional concerns because of their accessibility and frequent contact with patients. Medication reviews, chronic disease management services, and routine consultations all provide opportunities to discuss nutrition. By integrating nutritional assessment into wound
care conversations, pharmacists can contribute to improved healing outcomes and better overall patient care.
Part 6: Emerging evidence and the future role of pharmacists in wound care
Specialised nutritional support for wound healing Traditional nutritional interventions focus on ensuring adequate intake of calories, protein, fluids, vitamins, and minerals. However, increasing attention is being paid to specialised nutritional formulations designed specifically to support wound healing. These products are commonly used in patients with pressure ulcers, diabetic foot ulcers, and other chronic wounds where standard dietary measures may be insufficient.
Arginine and wound repair
Arginine is a semi-essential amino acid that becomes particularly important during periods of physiological stress.
It contributes to collagen synthesis, immune function, and the production of nitric oxide, a molecule involved in blood vessel dilation and tissue perfusion. Several studies have suggested that arginine-enriched nutritional supplements may improve healing outcomes in selected patients with chronic wounds, although benefits may vary depending on patient characteristics and overall nutritional status.
Glutamine and cellular recovery
Glutamine is the most abundant amino acid in the human body and serves as an important fuel source for rapidly dividing cells, including immune cells and intestinal epithelial cells. Interest in glutamine supplementation has grown because of its potential
role in supporting immune function and recovery from injury. While
some evidence is promising, routine supplementation remains an area of ongoing research.
Beta-hydroxy beta- methylbutyrate (HMB) Beta-hydroxy beta-methylbutyrate, commonly known as HMB, is a metabolite of the amino acid leucine. HMB has attracted attention for its ability to reduce muscle protein breakdown and support protein synthesis. Nutritional products containing HMB, often combined with arginine and micronutrients, have shown encouraging results in some studies involving older adults and patients with pressure ulcers.
Current evidence and ongoing challenges
Although specialised wound- healing supplements have generated considerable interest, the quality of evidence varies between studies. Differences in patient populations, wound types, and outcome measures make direct comparisons difficult. Furthermore, nutritional interventions are rarely effective in isolation and should be viewed as one component of a comprehensive wound management strategy that includes appropriate wound care, infection control, and management of underlying disease.
The evolving roleof pharmacists
As the understanding of nutrition and wound healing continues to develop, pharmacists are increasingly well positioned to contribute to multidisciplinary wound care. Community pharmacists can identify patients at risk of malnutrition, support the appropriate use of oral nutritional supplements, review medicines that may impair healing, and provide evidence- based advice regarding nutritional interventions. Their accessibility places them in an ideal position to reinforce dietary recommendations and promote adherence to treatment plans.
Future directions
Future research is likely to focus on personalised nutrition, targeted supplementation, and a better understanding of how specific nutrients influence cellular healing pathways. Advances in nutritional science may allow more tailored approaches to wound management, particularly for older adults and individuals with complex chronic conditions. As evidence continues to emerge, pharmacists will remain important contributors to optimising nutritional care and improving wound healing outcomes. ?
Written by Eamonn Brady (Pharmacist). Whelehans Pharmacies, 38 Pearse St and Clonmore, Mullingar. Tel 04493 34591 (Pearse St) or 04493 10266 (Clonmore). www.whelehans.ie
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