God's original design for food consumption was primarily to be fuel, but I believe He also gave things good flavor so that we would enjoy eating too. Of course, we have gotten where over-indulgence is the standard instead of the exception, and that often wreaks havoc with our bodies. As we get older there are certain things to consider, and if you have a neurological disease, there is even more to take into account.
This is not the time to be lazy about your diet. In Parkinson's for example, the lack of dopamine in your system does not allow your body to process foods like it used to. Not only is constipation a common ailment, but if you are eating the wrong things, you might find you have frequent diarrhea and more bowel movements in a day. You might not care about that, but for a care partner who spends time cleaning you up, that might be a concern!
The best advice I can give is "BALANCE". If you feel you have to eat those chips, then at least have a good helping of vegetables along with them. Any greasy foods like potato chips, processed foods, fried foods, rich meats, and dips, will cause your stools to slide right through you. So, compensate by eating more bulk; legumes, bananas, berries, almonds, sweet potatoes, apples, quinoa, broccoli. You can get an extensive list from our doctor or from the internet...easy peasy.
If your loved one is a picky eater, find a couple of bulk items on the list and figure out new ways to fix them. It might be a challenge to find a good balance for some but keep trying. Make it a game. Try to find a new way to fix an old meal and see how well your loved one takes to it. The internet has amazing recipes for just about anything. If you have access to Alexa or Ciri, ask them to find a recipe that uses the ingredient you want. Our world of technology is a great assistance.
Finding healthy balance for your loved one's diet can make a huge difference in the way your loved one's body processes. And in turn. it might free up a little time in the care partner's schedule, too. And that's a win all around!