you cannot ward off disease or improve (physical) wellbeing by eating a certain diet.
Nonsense. Following a healthy eating plan and exercising is far better for you than eating junk and not exercising. I'm not talking about any particular diet, I'm talking about scientific nutrition.
Our bodies are incredibe; they work to synathise energy at the cell level which requires specific proteins.
If diet didn't matter, why on earth would the NHS promote a healthy, balanced lifestyle?
OP your diet is normal, as far as the convenient Western diet goes. It could be a lot worse and I'm sure on good days you're getting lots of nutrients!
I'm an annoying Chia-seed, maca powder, spirulina-eater, but I'm in the minority and I wouldn't be so hypocritical sitting here with my G&T to judge anyone for what they choose to eat. If you want to live off takeaways and chocolate, that's your look out. Just don't expect to be the picture of health.
I've been at the other end - I used to be obese and I was very unwell (M.E.) and my lifestyle as far as diet and exercise has been a huge catalyst for changing my life completely. I'm now a size 10 marathon runner and my health issues have disappeared.
There are so many reasons why people eat what they eat - psychologically as well as practically. But if individuals considered the base nurtients of food and their needs, they may choose differently. Or they may not - such is free choice. :)