You don't really need to use sugar though it does help not only to sweeten it but also to preserve the jam. You can also use Honey, Brown Sugar, Maple Syrup, Coconut Sugar.. Or, I like to use pure Allulose for a sugar alternative. It tastes almost exactly like sugar but is about 70% as sweet and does not soike your glucose. It can brown and caramelize just like sugar too except it can brown a little bit faster, so maybe keep an eye out for that if you use Allulose. The downside, Allulose is rather expensive. But if you use it sparingly it is a great alternative. And coconut sugar is my next favorite alternative to regular cane sugar as it is generally quite low on the Glycemic Index. Hope that helps! Happy Jamming! 😊✌