Helpful Information I Found on a Website:. Kashrut is the body of Jewish law dealing with what foods we can and cannot eat and how those foods must be prepared and eaten. "Kashrut" comes from the Hebrew root Kaf-Shin-Reish, meaning fit, proper or correct. It is the same root as the more commonly known word "kosher," which describes food that meets these standards. The word "kosher" can also be used, and often is used, to describe ritual objects that are made in accordance with Jewish law and are fit for ritual use.
Contrary to popular misconception, rabbis or other religious officials do not "bless" food to make it kosher. There are blessings that observant Jews recite over food before eating it, but these blessings have nothing to do with making the food kosher. Food can be kosher without a rabbi or priest ever becoming involved with it: the vegetables from your garden are undoubtedly kosher (as long as they don't have any bugs, which are not kosher!). However, in our modern world of processed foods, it is difficult to know what ingredients are in your food and how they were processed, so it is helpful to have a rabbi examine the food and its processing and assure kosher consumers that the food is kosher.
There is no such thing as "kosher-style" food. Kosher is not a style of cooking. However, health is not the only reason for Jewish dietary laws. Many of the laws of kashrut have no known connection with health. To the best of our modern scientific knowledge, there is no reason why camel or rabbit meat (both treif) is any less healthy than cow or goat meat. In addition, some of the health benefits to be derived from kashrut were not made obsolete by the refrigerator. For example, there is some evidence that eating meat and dairy together interferes with digestion, and no modern food preparation technique reproduces the health benefit of the kosher law of eating them separately.
In recent years, several secular sources that have seriously looked into this matter have acknowledged that health does not explain these prohibitions. Some have suggested that the prohibitions are instead derived from environmental considerations. For example, a camel (which is not kosher) is more useful as a beast of burden than as a source of food. In the Middle Eastern climate, the pig consumes a quantity of food that is disproportional to its value as a food source. But again, these are not reasons that come from Jewish tradition.
The short answer to why Jews observe these laws is: because the Torah says so. The Torah does not specify any reason for these laws, and for a Torah-observant, traditional Jew, there is no need for any other reason. Some have suggested that the laws of kashrut fall into the category of "chukkim," laws for which there is no reason.