We are all for keeping work at work because burning out is a thing. But it is important to plan out your work lunches ahead of time.
Why? Dedicating an hour or two on your Sunday saves time Monday - Friday, morning and nighttime. Instead of taking an hour after work to make a meal, you can cook multiple meals at once on Sunday. Meal prep isn't only a fitness freak routine; it's for everyone!
Meal prepping allows you to make healthier choices. Healthier choices result in a better and more alert work day. When you do not prepare your work lunch, you are more likely to choose the greasy, unhealthy and sleep inducing option. This does not mean you can't attend Happy Hour with your colleagues or engage in Free Lunch Fridays, because this is highly encouraged to increase office camaraderie. But you will have an additional hour to yourself after work to: workout, FaceTime with friends/family, read a book, etc.