Registered dietician Kristen Smith says one serving of ice cream provides 10% of the calcium we need daily. And calcium is proven to reduce tension and anxiety. Plus, the fat in ice cream helps our body absorb minerals and nutrients that help regulate mood. Which is why people who eat full-fat foods have lower rates of depression than people on low-fat diets. So how much ice cream can we have daily? One half-cup. That’s about the size of a tennis ball. If you’re watching your calories, get slow-churned ice cream. It contains more air, which means fewer calories per serving.