Chronic Diseases and Cancer

I have been informed well that when we have the adequate and right nutrition we can bypass several chronic diseases and illnesses. However, I have a concern that it may be possible that newer diseases that have developed might be a result of messing with the natural biological processes of regular animals such as mice or rats. We have found positive results such as a B vitamin reducing the obesity in some mice right..but how much health have we sacrificed to come to the advancements in the medical field we have? A lot of times there is mutation or some change in the biological processes that cause a disease or disorder even. Could it possibly be because of the things we have exposed ourself to now? How safe are the products that we really have marked as safe? With just one change in our genes if changed chemically can cause sickle-cell anemia! It's interesting Valine is the replaced gene that causes it. It just makes me wonder. I know that even science isn't perfect so it makes me wonder if they grow clones from different parts of other animals or bacteria and introduce things to them then how immune are we really if some chemical alteration affects our genes prematurely or down the road in the process of Meiosis when their is a production of daughter cells. See we as humans can't understand all of this fully, we have come quite a long way though and applauds to the research. I'm just wondering how much we have really sacrificed to come to the conclusions we have. This is a problem I see, once people get so far they tend to lack or refuse any sense of guidance and rely on an I'm always right hypothesis in science or religion both. It makes me wonder if we don't work on our logic and reasoning and don't try to make sense out of what we have how we can really mislead ourselves or convince ourselves so surely of anything. How can we teach others when we need to work on ourself? It's a problem that is hard for me to watch. Not trying to put anyone down, I'm just saying that I think science and religion sorta prove each other and the independents..well just as they have from the beginning they usually struggle. I even know that from my own measure of independence!