True story: During WWII, sailors and aviators in the Pacific theater who were stranded and awaiting rescue often suffered from illness due to their having consumed whatever sea life they could catch. A research study was begun in order to establish a handbook for service men to help them identify what was safe and what to avoid. After much study and expense, the researchers came back with a simple guideline: "Tell them if it has fins and scales, it's probably safe to eat."
Well, isn't that special? God said that way back in Leviticus. Fact is that every single study today confirms why God said to leave unclean animals, birds, and sea life off the menu: It'll make you sick and eventually kill you.
If you want to be healthy, here's a tip: There are 5 "Blue Zones" in the world; places where the inhabitants of such zones are the healthiest and longest lived people anywhere. Before you say, "Well, that's a genetic link common to the occupants of each zone", hold on. There is one found in the U.S. in Loma Linda, California, and it is comprised of people of many, many different genetic backgrounds. They belong to the Seventh-day Adventist church and practice the Old Testament dietary laws, including not eating pigs and shellfish and most of them are vegetarians, the diet that God originally prescribed. These folks enjoy a drastic decrease in risk factors of cancer, cardiovascular disease, stroke, diabetes, etc., and live an average of 8-10 years longer than the median age with a quality of life that is unmatched. The sickest Christians are the ones who ignore those dietary laws in the name of "freedom in Christ", and after having consumed vast quantities of fat, cholesterol, alcohol, tobacco, dairy, refined foods, and sugar, they weep and beg God to heal them of their diabetes, heart disease, cancer, tumors, emphysema, etc., when the power to be healthy is found in God's Word and confirmed by modern day experts. Those Adventists seems to be on to something and even preachers like Joel Osteen are starting to preach that pork, shrimp, and lobsters are not God's gift to man's appetite.