Well first of all, why do we need calories, what are they? Calories are used to keep our bodies functioning even when we are sleeping! We burn them up just by breathing but weight loss using the breathing only method is very slow - believe me - I've tried that one too!!
So to recap - calories provide energy for our physical activities, in other words they are the fuel to keep us going. To answer the question above - how many do we need, varies from person to person. We have to take into consideration our physical makeup and lifestyle, how many cream cakes we eat and how many push ups we do after them....
The UK Department of Health Estimated Average Requirement (EAR) suggests a daily calorie intake of approximately 2,000 calories per day for women and 2,500 for men.
So - to lose weight, for example 1lb per week, which is what I'm aiming for, you need to reduce your usual calorie intake by 500 calories per day, preferably through a combination of eating less and exercising more. I am trying to increase my activity level to 500 calories a day over what I eat but I've slowed right down on the weight loss. So I'm making sure I do 2 hours a day of something.
Walking for a total of 30 minutes a day, or 60 for children, meets the Chief Medical Officer's minimum recommendations for physical activity. Think about how you can build 30 mins a day in and then slowly increase it each week. It doesn't have to be a 30 minute block - try 3 10 minute strolls!