Lemon Balm (Melissa officinalis) – Support for Equine Digestive Health Backed by Scientific Research (Including Human Studies)

Lemon balm (Melissa officinalis) has long been recognized for its calming and digestive-soothing properties. Recent scientific studies highlight its potential in reducing inflammation, promoting ulcer healing, and acting as an antimicrobial agent. Although there are limited studies conducted directly on horses, findings from human and laboratory animal research (e.g., rats) offer valuable insights for veterinary application.

1. Gastric Ulcers in Horses – A Common Health Issue Equine Gastric Ulcer Syndrome (EGUS) is particularly common in sport horses exposed to stress and suboptimal feeding conditions (limited forage, irregular feeding). Excess stomach acid and inadequate mucosal protection lead to lesions, causing weight loss, pain, and performance decline.

2. Lemon Balm's Active Compounds and Anti-Ulcer Potential Lemon balm contains several biologically active compounds contributing to its anti-inflammatory, antioxidant, and calming effects:

• Rosmarinic acid

• Caffeic acid

• Flavonoids (e.g., luteolin, quercetin)

• Essential oils (citral, geraniol)

These compounds support gastrointestinal health and may aid in the prevention and treatment of ulcers.

3. Extended Research Overview

3.1 Anti-inflammatory and Antioxidant Effects

• Shakeri et al. (2016): A comprehensive review in the Journal of Ethnopharmacology emphasized lemon balm's strong anti-inflammatory and antioxidant properties due to rosmarinic acid. In vitro results showed reduced inflammation markers, suggesting mucosal protection.

• Dastjerdi et al. (2012): In rats with induced colitis, lemon balm extract reduced inflammation and promoted tissue repair.

3.2 Antibacterial and Anti-Ulcer Effects

• Keivani Hafshejani et al. (2015): In rats with indomethacin-induced ulcers, lemon balm reduced ulcer size, with effects slightly weaker than ranitidine, a common anti-ulcer drug.

• Miraj et al. (2017): Lemon balm extracts were shown to inhibit bacterial strains such as Helicobacter pylori, a contributor to ulcers in humans.

3.3 Calming and Anti-Stress Effects (Important for Ulcer Prevention)

• Cases et al. (2011): A placebo-controlled clinical trial found lemon balm extract significantly reduced anxiety and improved sleep.

• Kennedy et al. (2004): Lemon balm reduced cortisol (stress hormone) levels in humans. In horses, cortisol control is crucial, as chronic stress can increase acid secretion, raising ulcer risk.

3.4 Equine-Specific Observations

• Nagy et al. (2015): Horses receiving a herbal blend with lemon balm were calmer during transport and in new environments, reducing stress-related digestive issues.

• Veterinarian and breeder reports suggest lemon balm, often combined with chamomile or fenugreek, helps improve appetite and soothe digestive discomfort in ulcer-prone horses.

4. Mechanisms Supporting Gastric Health in Horses

• Stress reduction: Less acid secretion, improved appetite, relaxed nerves

• Anti-inflammatory action: Mucosal healing and inflammation control

• Antimicrobial effects: Inhibiting bacteria that worsen ulcers

5. Summary Lemon balm offers a range of scientifically supported properties – calming, anti-inflammatory, antimicrobial – beneficial for equine digestive health, especially ulcers. Although direct equine studies are limited, cross-species evidence supports its use in ulcer management and prevention. Any suspected ulcer symptoms should be evaluated by a veterinarian to determine appropriate treatment and phytotherapy options.