Microwaving fruits & vegetables kills all their essential nutrients?
WHAT THEY’RE SAYING
Microwaving destroys the beneficial compounds in fruits and vegetables, so eating them has no benefit to you.
WHAT WE KNOW
The cooking process can cause some destruction of beneficial compounds in fruits and vegetables (phytochemicals, antioxidants, vitamins, minerals), BUT it can also make some beneficial compounds (such as lycopene) more available to the body.
In fact, microwaving is actually a good way to minimize the loss of nutrients! The nutrients of most concern when microwaving are the water soluble vitamins: vitamin C and the B vitamins. These vitamins are lost more easily during the cooking process, because they easily move into the cooking water. The fat-soluble vitamins (A, D, E, and K) are not as easily lost in the water during the cooking process.
HOW DO WE KNOW THIS?
A review in the Journal of Food Composition and Analysis found higher retention values of water-soluble vitamins in foods that were prepared in the microwave, steamed, or stir-fried. Vitamin C in spinach and green beans cooked in the microwave had a mean retention of up to 79% when compared to 66% retained when boiled. Another study cited in the article found that retention of vitamin C was the highest in fresh broccoli, cauliflower, potatoes, frozen corn, and peas cooked by microwave steaming, followed by microwave-boiling, stovetop steaming, and stovetop boiling. Folate, vitamin C, retinol (a from of vitamin A), and thiamin (B1) seem to be most affected by the cooking process.*
The difference in nutrient quality caused by cooking (including microwaving) is very minimal! The most important thing is that you are eating your fruits and veggies! No matter how you prepare them, or what form—fresh, frozen, canned, dried, or 100% juice—you prefer, consuming fruits and vegetables is much more beneficial to you than not consuming them at all!
A bigger concern with microwave ovens is food-borne illness. Here are some key ways to diminish your risk of contracting a food-borne illness when using a microwave:
- Clean microwaves with baking soda and vinegar at least once a week (especially in office settings)!
- Make sure your refrigerator is held at 40° F to decrease the growth of bacteria in leftovers and other food products.
- When using an older microwave that does not have a turn plate, shift your food half way through the cooking process. This will minimize cold spots in your food where bacteria are not killed.
- Use a food thermometer to make sure your food is heated to 165° F—this ensure all bacteria is killed.
Check out our Top 10 Healthy Ways to Cook Fruits & Veggies
* Leskova, Emila, et al. “Vitamin Losses: Retention During Heat Treatment and Continual Changes Expressed by Mathematical Models.” Journal of Food Composition and Analysis (2006); (19) 4: 252-76.