What is diet?

Your diet is, quite simply, what you eat. There are two aspects to your diet: what foods you eat and how much of them you eat. To lose weight or maintain a healthy weight, you need to pay attention to both factors. If you eat all the right foods but they are in quantities that are too large, you will take in too many calories and will gain weight. If you eat the right amount of calories but you get them from only one food group, you will lack essential nutrients which may cause serious health problems.