Okay first, if you have never heard of midin, let me put you on to it. It is a wild jungle fern that grows in Sarawak, and it is only really available there and at certain specialty restaurants in KL. The hawker throws it in a screaming-hot wok with belacan, garlic, chilli and a splash of oil, and it comes out with this satisfying crunch at the curly tips. At around 140 calories a plate, it is legitimately a low-calorie dish and something you can eat a lot of without wrecking your deficit. Fair warning though: the numbers here are a ballpark estimate because hard nutritional data for midin is almost nonexistent. We are working from the components, not a lab test, so treat it as a rough guide.
What actually drives the calorie count is the oil. The cooking oil contributes roughly 88 of those 140 calories; the fern itself is barely anything. A hawker who is heavy-handed with the oil could easily push you from 140 to 180 or 200 calories for the same plate. If you are eating masak lemak style with coconut milk, that version runs about 380 calories because the santan contributes an extra 250 to 300 kcal on its own. The garlic-only version (masak bawang putih) saves you a little, coming in around 120 calories. If you are ordering this at a warung, ask for less oil (kurang minyak) and stick to the belacan or garlic versions rather than the lemak.