What foods are said to improve or increase or decrease a body function?

Certain foods are believed to enhance specific body functions; for example, omega-3 fatty acids found in fish can improve heart health and brain function. Leafy greens like spinach and kale are known to support digestive health due to their high fiber content. Foods rich in antioxidants, such as berries, may help reduce inflammation and boost the immune system. Conversely, excessive sugar and processed foods may impair metabolic function and contribute to weight gain.