Compare whole foods to processed "Vitamins", "supplements", etc.
These are toxins for your body to deal with. No matter how great the technology is - expensive, less expensive - in making the supplements, the truth is: the more you process a substance, the more you lose chemical balance and live nutrition (enzymes).
In fact, in nature, everything exists in balance. When you remove some constituents, the substance becomes toxic.
As far as your health goes, if you read Norman Walker, for example, you'll find out that the answer to your question is simple - our colon gets compacted over time, and changes its shape. Every part of the colon meanwhile, corresponds to some organ in your body. You see where I am heading?
Older times, doctors used to come to the house of the sick person and give them an enema - that was the best treatment.
Another part why you feel worse, is stress. Actually, it's the biggest problem - your emotions, subconscious mind, your attitude all effect how you feel.
Your doctor spends only 5 minutes with you, so he can't help you. You need to take care of yourself.
I use therapeutic grade essential oils to balance, cleanse, heal and help handle stress. It is easy and very effective.
However, I try to eat/drink well and move outdoors.
All I have written is not only from reading, but also from experience.