Keloids are fibrous growths that form at sites of skin injury. They are benign skin growths that extend beyond the original wound margins. Keloids can occur after surgery, body piercing, acne, chickenpox, cuts, scratches, insect bites, burns, and other skin injuries. They are more common in people with darker skin tones, but can occur in anyone. Keloids do not regress over time and have a strong tendency to recur after surgical removal. There are several factors that contribute to keloid formation, including genetics, skin tension, wound infection, hormone changes, and nutritional deficiencies. Deficiencies in certain vitamins and minerals have been associated with increased keloid risk and poor wound healing. Identifying and correcting these deficiencies may help prevent or improve keloids.
What are keloids?
Keloids are fibrous overgrowths that form at sites of cutaneous injury. They extend beyond the borders of the original wound and do not regress spontaneously over time. Keloids can vary greatly in size and shape. They are described as:
- Smooth, rubbery lesions or hard, fibrous nodules
- Flesh-colored, pink, red, or darker than surrounding skin
- Sometimes painful or pruritic (itchy)
- Can restrict movement if over a joint
Keloids continue to evolve over the course of several months or years. They often expand into surrounding normal skin and rarely regress. Keloids differ from hypertrophic scars, which are raised scars confined to the area of injury.
What causes keloids?
The exact mechanisms leading to keloid development are not fully understood. Keloids are the result of abnormal wound healing in genetically susceptible individuals. They form due to excess deposition of dermal collagen and other extracellular matrix components during skin injury repair. The main factors believed to promote keloid formation include:
- Genetic predisposition – family history is a major risk factor
- Skin tension at wound site
- Prolonged inflammation and delayed wound healing
- Hormonal influences – keloids are more common during puberty and pregnancy
- Skin trauma – surgery, burns, piercings, acne, etc.
- Nutritional deficiencies
Keloids do not form without skin trauma. People with a genetic predisposition develop keloids more readily after skin injuries within prone sites with high tension, such as the chest, shoulders, upper back, and ears. The tendency for abnormal scar formation has a suspected autosomal dominant inheritance pattern.
Nutritional deficiencies associated with keloids
Nutritional deficiencies can contribute to excessive scarring by impairing early wound healing and prolonging inflammation. Certain vitamins and minerals play important roles in collagen synthesis and the formation of new skin after an injury. Deficiencies in these micronutrients can lead to poor wound repair and abnormal scarring.
Vitamin C
Vitamin C is essential for collagen production and cross-linking. It serves as a cofactor for enzymes involved in collagen synthesis. Vitamin C also has antioxidant properties that help quell excessive inflammation.
Studies show that lower vitamin C intake and blood levels are associated with more postoperative keloids. Vitamin C deficiency leads to impaired collagen synthesis, delayed wound closure, and easier keloid formation. Ensuring adequate vitamin C intake promotes proper wound healing and may help prevent keloids.
Vitamin A
Vitamin A is needed for normal epithelial tissue regeneration. It helps modulate inflammatory cells important for wound repair.
Vitamin A deficiency causes keratinization of epithelial cells, making skin dry and fragile. Lack of vitamin A alters collagen composition and wound breaking strength.
Low vitamin A levels can lead to excessive scarring and keloid formation. Supplementation may enhance wound healing and reduce keloid recurrence after surgical removal.
Vitamin D
Vitamin D signals wound healing pathways involved in inflammation, epithelialization, and collagen deposition. Deficiency impairs these processes.
Observational studies show an association between vitamin D deficiency and increased keloid severity. Low vitamin D status is linked to dysregulated inflammation and fibroblast activity.
Maintaining adequate vitamin D may help modulate keloid formation and symptoms. However, clinical trials are needed to determine whether supplementation reduces recurrence after treatment.
Vitamin E
Vitamin E has antioxidant properties that can help control inflammation during wound healing. It may also help regulate collagen synthesis and cross-linking.
Small clinical studies provide some evidence that topical or injected vitamin E improves keloid appearance and symptoms. Oral vitamin E has not been well studied for keloids. More research is needed to establish efficacy and optimal dosing approaches.
Zinc
Zinc assists with collagen matrix formation and cell proliferation needed for re-epithelialization. Zinc deficiency impairs immune function, increasing inflammation and infection risk.
Zinc deficiency is associated with delayed wound closure and keloid development. Zinc supplementation, often with other micronutrients, may enhance wound healing and help prevent keloids. However, large clinical trials are lacking.
Other nutrients
Other nutritional deficiencies linked to abnormal scarring include:
- Protein – needed for collagen production and tissue regeneration
- Iron – involved in collagen synthesis and wound repair
- Copper – cofactor for enzymes that cross-link collagen fibers
- Manganese – facilitates collagen formation
- Silicon – involved in collagen maturation and stabilization
Adequate intake of protein, iron, and other nutrients supports timely wound healing and balanced collagen deposition. Nutritional optimization may help reduce keloid risk after skin injury.
Assessing nutritional status
Nutritional status can be assessed through:
- Diet history – identify adequate micronutrient intake from foods
- Signs of deficiency on exam – brittle nails, hair loss, poor wound healing
- Lab tests – serum levels of vitamins, minerals, proteins, etc.
People prone to keloids should ensure they meet the Recommended Dietary Allowance (RDA) for vitamins and minerals important for wound healing. Those with poor intake or signs of deficiency may benefit from supplementation prior to procedures like surgery to help prevent keloids.
Improving nutrition to prevent keloids
The following nutrition tips may help reduce keloid risk:
- Eat a balanced diet with sufficient protein, vitamins, and minerals
- Ensure adequate intake of vitamins C, A, D, E, and zinc
- Take a multivitamin to help meet micronutrient needs
- Increase fruits, vegetables, nuts, seeds, fish, and whole grains
- Consider targeted supplementation if deficient in specific nutrients
- Aim for any needed weight loss to improve wound healing
- Stay well hydrated to support skin health
- Avoid nutrient deficiencies that can impair wound healing
For those with a history of keloids, correcting nutritional deficiencies prior to elective surgeries or piercings may help prevent recurrence at wound sites. Individualized nutrition plans should be developed with the assistance of a dietitian or nutritionist.
The role of nutritional supplementation
Evidence suggests certain nutritional supplements may help prevent or improve keloids when deficiencies exist, including:
- Vitamin C: 500-1000 mg daily to support collagen formation
- Vitamin A: Per RDA levels to promote epithelialization
- Vitamin D: Correct any deficiency to modulate inflammation
- Vitamin E: 400-800 IU daily for antioxidant effects
- Zinc: 30 mg daily for wound healing
- Silica: Possible role in collagen stabilization
- Bromelain: Anti-inflammatory enzyme from pineapple
However, research on supplementation for keloids is limited. Work with a healthcare provider to identify any nutritional deficiencies. Targeted supplementation should be considered as an adjunct, not alternative, to conventional medical keloid treatments.
Medical treatments for keloids
First-line medical treatments for keloids include:
| Treatment | Description |
|---|---|
| Intralesional corticosteroid injections | Corticosteroids help suppress inflammation and collagen production. They are injected directly into keloids. |
| Cryotherapy | Freezing keloids with liquid nitrogen to induce tissue injury and subsequent fibrosis and collagen breakdown. |
| Silicone sheets/gel | Silicone sheets applied directly to keloids can flatten and soften them. |
| Radiation | Radiation is used to help prevent recurrence after surgical keloid removal. |
| Laser therapy | Lasers are used to remove keloids and improve symptoms. |
Second-line treatments include surgical keloid excision and interferon injections. Recurrence rates after treatment remain high. Combined modalities are often needed for optimal results. Nutritional optimization may help improve outcomes when combined with medical therapy.
The impact of diet on wound healing
Diet and nutritional status have clear impacts on wound healing processes:
- Protein deficiency impairs collagen production and tissue granulation
- Carbohydrate excess increases inflammation and infection risk
- Fatty acids modulate inflammatory pathways and cell signaling
- Vitamin C deficiency weakens collagen cross-linking
- Zinc deficiency delays epithelialization and closure
- Iron deficiency reduces collagen formation and strength
Hypermetabolic states after major surgery or burns increase nutrient needs. Nutrition support can help provide adequate protein, vitamins, minerals, and calories needed for optimal healing.
Diets high in processed foods and low in fresh fruits/vegetables are often deficient in wound healing nutrients. A whole food, balanced diet supports timely healing.
Diet tips to optimize wound healing
- Meet daily protein needs to support tissue repair
- Reduce sugar intake to prevent impaired immunity
- Eat plenty of vitamin C-rich fruits and vegetables
- Ensure adequate zinc intake to prevent epithelial defects
- Increase healthy fats like olive oil and avocados
- Stay well hydrated with water
- Limit alcohol intake as it delays healing
- Avoid nutrient deficiencies through a balanced diet
For major surgery, trauma, or burns, work with a dietitian to ensure nutritional needs are met, especially increased protein and calories.
Conclusion
Keloids are abnormal scars that extend beyond wound borders and rarely regress. They result from excessive collagen deposition in genetically prone individuals after skin injuries like surgery, piercings, and acne. Nutritional deficiencies in vitamins C, A, D, E and minerals like zinc can impair wound healing and promote keloid development. Assessing nutritional status and correcting any deficiencies through diet and targeted supplementation may help prevent keloids after elective procedures. While research is limited, nutrition optimization is an adjunctive strategy to improve outcomes when combined with conventional medical treatments for keloids.