It's naturally sweet thanks to the fruit, and don't worry because the spinach is undetectable thanks to the zestiness of the citrus, slight tartness of the cranberries (one of my favorite holiday superfoods), and natural sweetness of the apple, pineapple, and banana. (heathermcclees.com)
You can either increase or decrease the amounts of either of these, but I found 1 tsp honey to give just a very slight sweetness, and the lemon to add a very slight tartness to bring out the buttery avocado. (doublechindiary.com)
Their version had large chunks of salty feta cheese and a slight tartness from vinegar that balanced the sweetness from the pumpkin perfectly, so we made ours the same way. (greenkitchenstories.com)