Watching one's weight involves maintaining a healthy balance between the calories consumed and the amount of energy expended. Synonyms for watching one's weight would include monitoring one's food intake, staying mindful of what you eat, tracking your calorie intake, being cautious of your diet, and controlling your portions. Another synonym would be to maintain a healthy eating behavior or a healthy lifestyle, which promotes healthy eating habits and physical activity. It is important to remember that watching one's weight is not just about losing weight but also about maintaining a healthy lifestyle that promotes overall physical and mental well-being.