"Food miles" is a concept that is often tossed around in environmentally concerned circles these days. You may have seen celebrity chefs discussing the concept of food miles during their cooking shows, or you may have seen advertisements which make people aware of the food miles issue. Personally, it has both pros and cons.
Maybe local food is more environmentally favorable.The reason usually given for this is that imported food requires a lot of fossil fuel (and produces a lot of carbon emissions) to get it to the market. Locally grown food, however, requires less fossil fuel and therefore puts out less carbon/greenhouse emissions and is better on a global scale. However, the food miles argument has a few flaws to some extent. One popular image that has been buzzed around by the media regarding the "imported food" issue is the idea that the produce is carried by air. Air transport is a very big producer of greenhouse gases (although the aviation industry is working on improving this) and the concept of produce freighted from one side of the world to the other is repellent to many environmentally aware people.'.However, it does enrich the diet of tables inthe local places and promote international transportation.
But, locally produced food is always fresher, which means that it usually has more vitamins and antioxidants in a useable way. They are better for people. Besides, fruits and vegetables that have been grown locally are probably allowed to ripen naturally for longer, rather than being picked under-ripe to reduce spoilage in transit. They may also not undergo certain treatment to increase their shelf life. What's more, locally grown vegetables usually vary according to seasons.What's in season and grown locally is usually cheaper. This is a way to save money and to add some variety into people's diet.
According to traditional Chinese medicine, in一season food has the right "stuff" in them to enhance ones health at that time of the year.So it is much better to have local food mainly and with imported food as supplementary dishes.