Thanks everyone for your comments.
I want to be clear that I'm not asking if it's important to eat healthy foods. Of course it is, and I've been doing it for years -- to the best of what I knew it at the time. My sugar intake already was very low (an occasional treat or piece of gifted pie put in front of me at a rare dinner party. What I didn't know that whole grains, beans, nuts, and seeds contain phytic acid which robs the body of important minerals needed for healthy bones and teeth. Every morning, I ate my favorite breakfast of Trader Joe's Shredded Mini Wheats (100% whole wheat and nothing else) topped with several almonds and milk. And my beloved morning coffee without sugar or cream. We eat mostly organic chicken, fish, turkey, occasional beef, fruits and vegetables. I had no gut issues, nothing to complain about.
Then along came my dental abscess that resulted from an old badly-done root canal, leading to extraction of that tooth. Pain meds and 3 rounds of antibiotics screwed up my gut. But during the aftermath I learned what Weston A. Price and Ramiel Nagel (the latter is the author of Cure Tooth Decay) say about phytic acid causing tooth decay. Out went my favorite morning cereal, oatmeal, any bread for that matter, coffee (caffeine can draw calcium from the bones), nuts and beans (unless soaked for long periods). In came bone broth (liquid gold!! But can be time-consuming to make), full-fat organic raw dairy (expensive), pastured/organic eggs (delicious and expensive), and dietary supplements including whole-food vitamins. I learned how important the fat-soluble vitamins are for teeth, bones and overall health. Vitamins A, D, and K (K2 is required for so many things including directing calcium into the bones instead of the arteries), the correct balance of each. I'm planning to purchase the cod liver / butter blend from Radiant Life for A and D, as it is claimed to reverse tooth decay by many who have used it.
All of that to say --- It is not as simple as eating whole grains, lots of fruits and vegetables, and avoiding sugar. There needs to be a balance of nutrients and plenty of healthy whole fats (butter, coconut oil) in our diet to use the fat-soluble vitamins.
My main question was NOT to ask if it's important to eat a healthy diet. I'm wondering how much time and attention we should give to these particulars, especially when it takes time away from serving others. Many times, my thoughts tell me "if you eat that bowl of oatmeal, or unless you take a lot of time to make bone broth and soak the beans and nuts etc., then God won't protect your health and your teeth will rot".
We are not to put our trust in food or vitamins or nutrients, but only in God who created us and cares for us -- not because of what we do but because of who He is. We should put healthy foods into our body to care for it, but trust God alone to bless it to our nourishment. Of course, there are health issues that require eating or avoiding specific foods for the sake of one's general health and well-being, and that's not what I'm addressing here. I'm asking about issues like preventing (or reversing minor cases of) tooth decay.
When I start feeling too neurotic about it all, and worried about every food that God provides me through a generous friend, that's when I begin to wonder if I'm going too far.