Whenever possible, you should eat whole foods, not processed foods. This means to eat a food as near as possible in its original state. In other words, eat an apple rather than an apple pastry. Eat fresh or frozen peas rather than buying a can that is loaded down with salt and other preservatives. The closer a food is to its natural state, the healthier it is for your body. If you live where you can, you should buy your foods daily or several times a week rather than once or twice a month. If that is not possible or you catch a good sale on something, go ahead and buy extra and freeze it for later.