Whenever I share my baby food recipes, in which I use my microwave to cook various fruits and vegetables to tenderness, I typically receive negative comments about the effects of microwaving on food. Although every American household owns a microwave, and microwaving has been a cooking practice for decades now, does it kill nutrients in food?
Nutrients are components in foods such as carbohydrates, fats, proteins and amino acids, vitamins, dietary minerals, water, and oxygen that an organism utilizes to survive and grow. Nutrients are necessary for living things to remain alive, but nutrients alone are not living. Thus, microwaving cannot “kill” nutrients in food.
However, cooking can change or destroy nutrients in food. Boiling, steaming, baking, frying, broiling, and grilling, as well as microwaving, can destroy vitamins and other nutrients in food. For example, boiling broccoli causes a decrease in glucosinolate, the sulfur-containing compound that may give the vegetable cancer-fighting properties. Cooking in water also causes many foods to lose nutritional value because nutrients and soluble fiber leach into the water. However, in some cases, cooking increases certain nutrients in food. For example, cooking tomatoes substantially raises the levels of beneficial compounds called phytochemicals. Therefore, although cooking foods can destroy nutrients, thinking about cooked foods in terms of nutritional changes provides a better foundation for evaluating the effects of microwaving on nutrients than asking if microwaves kill nutrients.
The best cooking methods for retaining nutrients are cooking quickly, heating foods for the shortest time and using as little liquid as possible. In many cases, microwaving meats all three criteria. I prefer to use my microwave to make baby food because microwaving is much faster than stovetop boiling. More complex foods like apples and pumpkins cook much quicker in my microwave than on the stove, thus decreasing cooking time. Because of the reduced time in the microwave, I also have to add less water during cooking, reducing the loss of nutrients. (When I make baby food, I also use the water in which I cook the fruits and veggies to make the puree or mash, further minimizing the loss of nutrients.) Thus, in many cases, microwaving food causes the least damage to the nutrients compared to other forms of cooking like boiling.
Additionally, microwaving can decrease the amount of harmful chemicals in some foods. For example, microwave-cooked bacon typically has lower levels of nitrosamines than conventionally cooked bacon. Most nitrosamines are carcinogenic, so lower levels in food are beneficial. Grilled and broiled meat, or heat-processed meat, also contains high levels of advanced glycation end products (AGEs), which may cause the development or worsening of many degenerative diseases such as diabetes, Alzheimer’s disease, atherosclerosis, and chronic renal failure.
While microwaving can be a quick and convenient way to cook food, prioritizing a balanced and varied diet to ensure you get all the nutrients your body needs is crucial. Additionally, following safe food handling practices when using a microwave to cook food is important. For example, stir food halfway through cooking and let the finished food rest for a few minutes after cooking to ensure even heating and prevent burns. By being mindful of the nutritional changes during cooking and taking steps to minimize nutrient loss, you can enjoy the benefits of using a microwave to cook food while maintaining a healthy and balanced diet.
The bottom line is that cooking food changes the nutritional content, for better or for worse. But microwaves generally do not completely destroy nutrients in food. And compared to other cooking methods, microwaving can sometimes be nutritionally advantageous.
This post was originally published on April 19, 2015, and updated on April 19, 2023.
References
Avoiding harmful byproducts of heat-processed foods protects against risk of Alzheimer’s disease and diabetes: http://icahn.mssm.edu/about-us/news-and-events/avoiding-harmful-byproducts-of-heat-processed-foods-protects-against-risk-of-alzheimers-disease-and-diabetes
The claim: Microwave ovens kill nutrients in food: http://www.nytimes.com/2006/10/17/health/17real.html?_r=0
Does Microwaving Food Reduce Its Nutritional Value?: https://www.healthline.com/nutrition/microwaving-food
Effects of heat processing on nutrients: http://link.springer.com/chapter/10.1007/978-94-011-7030-7_12
Effects of microwave cooking/reheating on nutrients and food systems: a review of recent studies: http://europepmc.org/abstract/med/3894486
Italian chefs knew it all along: Cooking plump red tomatoes boosts disease-fighting, nutritional power, Cornell researchers say: http://www.news.cornell.edu/stories/2002/04/cooking-tomatoes-boosts-disease-fighting-power
Microwave cooking and nutrition: http://www.health.harvard.edu/staying-healthy/microwave-cooking-and-nutrition
Microwave cooking and nutrient retention in vegetables: https://doi.org/10.1007/s13197-020-04320-1
Microwave cooking does not diminish the nutritional value of foods: https://www.eatright.org/food/vitamins-and-supplements/nutrient-rich-foods/microwave-cooking-does-not-diminish-the-nutritional-value-of-foods
Nutrient: http://en.wikipedia.org/wiki/Nutrient
The pros and cons of microwave cooking: https://my.clevelandclinic.org/health/articles/17466-the-pros-and-cons-of-microwave-cooking
Image Credits
Does Microwaving ‘Kill’ Nutrients in Food?: https://commons.wikimedia.org/wiki/File:TW_Panasonic_NN-S215.jpg and https://www.flickr.com/photos/kendallfrancis00/6213136139/ (CC BY-NC 2.0)
This is so interesting! Thanks for explaining it in such a clear way.
I never knew that using microwaves could have advantages, maybe I’ll start using ours as a microwave rather than a storage nook.