Roasting chestnuts takes away the raw and bitter taste.
Chestnuts are considered both a fruit and a nut, and they taste a bit like sweet potato when cooked.
They are less nutty than they are sweet and buttery when cooked.
You can eat a chestnut raw, but cooking it removes the shell and helps in lowering its tannic acid.
Tannic acid can cause stomach irritation, nausea and vomiting when consumed in large amounts.
Chestnuts are very good for you, since they’re high in Vitamin C, carbohydrates and fibre, but low in calories.
source: express.co.uk