Cardiologist Dr. Alok Chopra highlights five seasonal foods beneficial for boosting immunity during winter. He emphasizes that seasonal nutrition supports warmth, digestion, and reduces inflammation. The list includes mustard greens (sarson) for vitamins A, C, K, and antioxidants, and raw turmeric (kachhi haldi) for its anti-inflammatory compound curcumin. These foods are presented as crucial for strengthening the body's natural defenses and overall health.