"饮食与养生" can be translated into English as "Diet and Health Preservation" or "Food and Health Maintenance".
"Diet and Health Preservation" is a more formal and traditional expression, often used in contexts related to traditional Chinese medicine or holistic health practices.
"Food and Health Maintenance" is a slightly more contemporary and general-purpose translation, emphasizing the relationship between food choices and the maintenance of good health.
Both translations convey the essence of the original Chinese phrase, which refers to the practices and principles related to eating well for the purpose of maintaining or improving health.