Eggs
Chicken eggs are nutritionally rich, supplying almost every nutrient you need. They have one of the lowest energy-to-nutrient density ratios of any food and are useful sources of some of the harder-to-get nutrients like vitamins D and B12 as well as the mineral iodine.
Duck eggs are an excellent source of nutrition. Their dark yellow yolk indicates that they hold more antioxidants, more omega-3 fatty acids, and 50% more vitamin A than chicken eggs. Duck eggs offer more protein than chicken eggs, even taking size into consideration.