Can belly fat be reduced just by doing cardio?NOOOPE! There are two parts for this question. the First is loosing belly fat and the second loosing fat by Cardio:
1st: Our bodies don't choose which parts to take fat from like: belly, thigh or biceps. They reduce fat according to how our genes are programmed. So when we loose fat we can't choose which part i.e: we can't say I'll loose only my belly fat.
2nd: The conventional wisdom says: "If you want to loose weight then eat less and exercise more" which is based on the laws of thermodynamics which when applied to nutrition states that if you want to loose weight then you need to satisfy the equation: Calories In < Calories out. which means if you consume calories less than you expend you will lose weight AND that's why people focus on the cardio/exercise part (calories out) buuut this principle is right to a point. Mathematically speaking a 250 pound man burns three calories climbing one floor ==> so he needs to climb 20 floors to get rid of ONE slice of bread!! (a research done by University of Michigan in 1942) so if we take the Calories-in/ Calories-out and focus on Cardio/exercise to loose some pounds....guess what?.. You will never loose weight!!! this is a long subject for discussion so I'll go directly to the solution: If you want to get rid of your fat (not just belly fat because you can't choose) You have to focus on your F.O.O.D in a way that enables you to eliminate what we call Insulin Resistance (Read about this!) How will you do that? The ideas generally is to take out as much Carbohydrates as you can from your meals. by doing only this your body will start sucking the fat (belly fat included) as it's ice cream! Then you can opt for any diet you think is convenient for your lifestyle! (I suggest Slow Carb Diet by Tim Ferriss it's easy to implement and fun and I lost 40 pounds in 75 days on this one!!). last word: When it comes to loosing fat or being healthy in general our enemy is Sugar not Steak or butter or egg yolk! It's that white powder that we humans are so stubborn to declare consuming it on a daily basis as an addiction. If you can read just one book and its title is self-explanatory called "Why we get fat and what to do about it" by Gary Taubes. So step down from the treadmill and go straight to the kitchen!