The better choice between a microwave oven and an electric steamer largely depends on the specific cooking needs and preferences. Generally, a microwave oven is more versatile and quicker for reheating and defrosting, while an electric steamer is superior for preserving the nutritional value and texture of vegetables and fish.

Microwave ovens are widely used for their convenience and speed. They can heat food quickly, making them ideal for busy lifestyles or when time is limited. According to a study by the Journal of Food Science, microwave cooking can preserve more nutrients in food compared to traditional cooking methods like boiling or frying. However, microwave ovens may not be as effective for cooking delicate dishes like fish or vegetables, as they can dry out the food or cause uneven heating.

On the other hand, electric steamers are designed to cook food by steaming, which is a healthier cooking method as it doesn't add any fat or oil. Steaming is known to retain more vitamins and minerals in food compared to boiling, as it cooks at a lower temperature and doesn't leach nutrients into the water. A study published in the Journal of the Science of Food and Agriculture found that steaming can preserve up to 90% of the nutrients in vegetables, compared to only 50-70% when boiled. Electric steamers also provide a tender and moist texture to the food, making them particularly popular for preparing fish and vegetables.

In terms of convenience, microwave ovens are generally more compact and easier to clean. They can also be used for a variety of cooking tasks, from reheating leftovers to making popcorn. Electric steamers, however, require more space and are more specialized in their function. They are best suited for steaming vegetables, fish, and other delicate dishes.

In conclusion, the choice between a microwave oven and an electric steamer depends on the specific cooking needs. If versatility and speed are the top priorities, a microwave oven is the better choice. However, if the goal is to preserve the nutritional value and texture of food, especially for vegetables and fish, an electric steamer is the more suitable option.