Hi @artist01 - This may depend on what natural sugar you are talking about. For example, fruit and milk have natural sugar because sugar is in the fruit (fructose, glucose) and milk (lactose) in their original states. No sugar has been added to these products. Cane sugar could be considered "natural" as sugarcane is technically a plant.. but this is not how we eat it! Cane sugar is added to products to sweeten them. We would advise patients to limit foods with added sugars, which you'd be able to identify on a nutrition label. Have you checked out this article yet?
https://connect.mayoclinic.org/blog/weight-management-1/newsfeed-post/what-the-difference-between-added-sugars-and-natural-sugars/

Cane sugar is processed and artificially added to most foods and beverages. It contributes to a multitude of health issues including IBS, gas & bloating, acid reflux/GERD, and arthritis as well as puts you at high risk for heart disease, stroke, Alzheimer's, and diabetes when you consume in excess and/or on a daily basis over time.

Natural sugars are ones already contained in foods/beverages before they are harvested and/or processed, and carry little to no risk regardless how much you consume.