Sugar and jaggery both are obtained from the same source that is sugar cane. But the sugar is highly processed and jaggery is unprocessed-unrefined.
Moreover jaggery has health befinifits like it helps in digestion thus removes constipation. It has anti allergic properties if you take organic gur. It is rich in iron, calcium and phosphorus.
On the other hand sugar has been touted as a source of'empty calories' without any nutritional value.
So it is clear that jaggery is always better then sugar but it is important to remember that adding sugar or jaggery in your diet means adding excess calories'