For managing left-sided colitis, which is a form of ulcerative colitis, both dietary and supplement strategies can play an essential role in alleviating symptoms and promoting gut health.

Dietary Recommendations

1. Mediterranean Diet: This diet is recognized for its anti-inflammatory properties and has shown promising results for ulcerative colitis. It emphasizes high consumption of fruits, vegetables, whole grains, and healthy fats, such as olive oil[^1^][^3^].

2. Low FODMAP Diet: Reducing fermentable oligosaccharides, disaccharides, monosaccharides, and polyols intake can help some people by alleviating symptoms like bloating and gas[^2^].

3. Anti-inflammatory Diet: Focus on foods that reduce inflammation, such as leafy greens, nuts, fatty fish, and turmeric[^3^].

4. UC Exclusion Diet (UCED): Though new and requires further research, this diet may help some individuals by focusing on excluding specific foods that might exacerbate symptoms[^2^].

Supplement Recommendations

1. Probiotics: These can help in maintaining a healthy balance of gut bacteria, although the evidence is not definitive yet for ulcerative colitis specifically[^1^][^4^].

2. Omega-3 Fatty Acids: Found in fish oil, these are known for their anti-inflammatory effects and may be beneficial in managing symptoms[^2^][^4^].

3. Curcumin: The active compound in turmeric, curcumin has anti-inflammatory properties that could potentially help in reducing gut inflammation[^1^].

4. Butyrate, Phosphatidylcholine, and Silymarin: These have shown potential in maintaining the intestinal barrier function and reducing inflammation[^4^].

5. Vitamin D: Adequate levels might support immune function and gut health, although more research is needed[^1^].

Before starting any new diet or supplement regimen, it's always best to consult with a healthcare provider, especially for managing a condition like colitis.