Antibiotics, chlorine, dead bacteria (from pasteurization), fertilizers, bleaches, pesticides, and thats not all.
Take these and multiply by 20 and you will come close to the amount of concoctions used in our food to either preserve or sterilize our food.
These toxins are impossible for the body to process and as a result they can leak into the blood system and have dyer consequences.
Some will cause cancer while other can make you lose your hearing or worse. And the least of these your body will store in the linings of your gut and your intestines. This will cause weight gain at the very least and can cause a number of other complications such as: sinus trouble, ear infections, colds, the flu, liver disease, and even lung cancer.
Do yourself a favor and get educated so you can understand what you eating and why. It seems like some people care more about what we are doing to the environment and not what we are doing to our own bodies.
Then there are people that don't care at all about themselves and the people that surround them, these people will eat anything.