[masaegu]

Originally Posted by duo797

I believe I made a consistent spelling error because I meant to say 体に悪い not 健康.

You cay say 不健康だ or 身体に悪いのだ.

If you intend to study Japanese for many years, which I am certain that you do, try to write 体 as 身体(still read からだ) because 体 carries the connotation of "flesh" and better writers would almost always opt for 身体.

The only one I'm not entirely sure how to phrase is the 時間がかかる phrase. I had wanted to say 'It tastes good because it takes time to make.' Also I realize that in my original writing I had ことからだ instead of ことだ though I'm not sure if that makes any different.

You could say 「作るのに時間がかかるからおいしいのだ。」
To make it even better, insert こそ after the から.
You would need a much longer and complicated sentence if you used おいしさ as its subject.

Would 体にいいものを食べないと sound less redundant?

Yes. I knew you could correct it yourself.

And finally, I wasn't taught to use である I just felt weird about using い adjectives with だ because I don't have much experience. This was the only alternative that popped into my mind because I couldn't use です and I didn't want to just end the sentence with an adjective. Had I known that this was incorrect I would never have used it in the first place, so thank you for letting me know.

"I-adjective + のである". It's incorrect without the の.

To use だ体, you must say 悪いのだ. I often see Jaanese-learners use 悪いだ but that sounds incredibly wrong. Mistakes on particles always look and sound much more serious to the native speaker than the learner might think.

Hope I didn't miss any questions.