In the PropertySet of your item you need to set the RequestedBodyType to BodyType.Text. Here's an example:
PropertySet itempropertyset = new PropertySet(BasePropertySet.FirstClassProperties);
itempropertyset.RequestedBodyType = BodyType.Text;
ItemView itemview = new ItemView(1000);
itemview.PropertySet = itempropertyset;
FindItemsResults<Item> findResults = service.FindItems(WellKnownFolderName.Inbox, "subject:TODO", itemview);
Item item = findResults.FirstOrDefault();
item.Load(itempropertyset);
Console.WriteLine(item.Body);
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