Unfortunately, the health system focuses on only scans and medicine. My advice comes from over 100 books, SCIENTIFIC RESEARCH, and several doctors (not "Doctors)."
Focus on super healthy diet. Now, see doctors reports what deficiency your loved one has. No deficiency detected? No problem. Be sure your loved one is getting all the 26 vitamin and minerals on a DAILY basis. Light cooked or light steamed vegetables with brown rice, roti with daal or sabji (as we usually cook). In the morning drink a huge mug of Horlicks for breakfast (in warm water or milk), snacking should be fresh fruits.
Now, loved one may complain or say no but u must encourage and enable them. Will not be easy, hard 2 weeks, but six months down the line they may thank you. NO junk, NO fizzy. Just water, milk and fresh juices made from home.