Longan: warm and sweet, beneficial to heart and spleen, qi and blood.
Lycium barbarum: sweet in taste, flat in nature, nourishing kidney and essence, nourishing liver and improving eyesight, nourishing blood and calming nerves, promoting fluid production to quench thirst, moistening lung and relieving cough.
You don't need to eat or drink, just once or twice a day. Poor immunity, lack of qi and blood, you can drink more.
But no one has ever said that drinking this will make you fat. Need verification. Personally, some people will get fat if they drink boiled water.