That's ludicrous thinking.
What about all the medicines in the world? You're not gonna find those in your meals, but they're not going to be bad for you, are they?
What about Omega3 which is found in fish, but which doctors reguarly tell people (especially old folk) to take when suffering arthritis or just sore joints. You COULD eat more and more fish, but why do that? It forces you to change your diet so much to get increased amounts they may need. Omega3 can be found in liquid or tablet form it doesn't disrupt people's everyday lifestyle so why not take it. We have the technology to make it. Let's use it. It's not BAD FOR YOU! It has the same benefits and just because it's a tablet there are no more draw backs to that of eating fish. It's just more conveniant. I'd love to hear you argue that with a medical professional.
But what IS a natural daily diet?
We love in a modern world and natural doesn't mean "fat of the land" anymore.
Homemade smoothies made from fresh apples, bananas and milk is natural...just not packaged in a natural form. It's still good for you.
Herbal tablets are natural...just not packaged in a natural form - they're still good for you.
Protein powder is natural...just not packaged in a natural form. It's still good for you.
The point of my argument is: Just because it's convenient, doesn't mean it's bad for you.