Make sure your oncologist gives you the clearance to do whatever exercises you are wanting to do. Walking is great for weight loss if you keep doing it. Just a suggestion, mix up your workouts and walking for max efficiency. This way you could be walking three days a week and working out three. Alternate days. Check out body for life program as a starter. Supplement with unsweetened green tea two or three times a day to boost your metabolism. This is not really a supplement, as it is more of a food. However, it is useful in weight loss as well as beneficial for health and disease prevention. Follow the advice of others here for tips on proper eating. My personal advice for weight loss is to imagine a picture of a dinner plate in your mind: divide the plate into four sections like a pie. Put fruit in one section. Put meat in one section and put veggies in one section. Put starchy carbs in one section. Eat that one plate and that's it for that meal. This is nothing but portion control. Eat low carb snacks in between meals. drink plenty of pure water each day. The best way to lose weight is to burn up more calories than you take in. So you have to either eat less, or increase your metabolism. That's where using weights will come in handy. More muscle means more calories burned while you sleep and rest. You will not turn into a bodybuilder or get muscle bound no matter how hard you work out. Toning muscles will do wonders in my opinion. If all else fails or if you hate to work out, then do portion control and keep walking.