N. Ramalingam writes on natural and herbal medicine, emphasizing the healing properties of food and herbs. In his works, including உயிருள்ள மூலிகை மருத்துவம் (Uyirulla Mooligai Maruthuvam, Living Herbal Medicine) and மருந்தாகும் இயற்கை உணவுகள் (Marunthaagum Iyarkai Unavukal, Medicinal Natural Foods), he explores the principles of using natural remedies for health and well-being.