The jaggery is good for health in comparison to white sugar because it contains along with sugar other minerals and salts which are essential for the human health.In white sugar salts & micro nutrients are absent .
Jaggery helps in maintaining the electrolyte balance and helps prevent water retention thanks to its potassium content whereas sugar is responsible for inducing sudden blood sugar spikes which leads to weight gain. Replacing sugar with jaggery is a healthier option. https://m.timesofindia.com/life-style/food-news/is-jaggery-healthier-than-sugar/amp_etphotostory/68939464.cms
Jaggery contains more nutrients than refined sugar because of its molasses content. Molasses is a nutritious by-product of the sugar making process, which is usually removed when making refined sugar. Including the molasses adds a small amount of micronutrients to the final product. https://www.healthline.com/nutrition/jaggery
You can substitute jaggery for granulated white sugar in many recipes-you will need to use about one-and-a-half times the amount of jaggery to achieve the equivalent level of sweetness. https://www.yogajournal.com/lifestyle/sweet-switch