Broccoli, garlic, bell peppers … when processed with high temperatures such as sautéing, microwaves will destroy many nutrients.


Broccoli contains large amounts of phytochemical sulforaphane, which helps to prevent cancer, heart disease, inflammation, and depression. According to scientists, the body absorbs sulforaphane faster when eating raw broccoli instead of cooked. Making broccoli by microwave, boiling and stir-frying also reduces the amount of vitamin C. If you still want to eat it, you can steam it. This method has the least effect on the nutrients of broccoli.


Garlic contains allicin which helps to increase the body’s resistance, prevent flu, cancer. However, under the effect of heat, allicin is very volatile. Heating garlic at 200 degrees C for 6 minutes completely inhibited the antiplatelet activity of garlic. Garlic boiled for 20 minutes will completely inhibit antibacterial activity and just one minute in the microwave has destroyed 100% of its anti-cancer ability.


Onions can prevent cancer thanks to the flavonoid quercetin. When eaten raw, you will absorb maximum flavonoid quercetin. A 2012 study found that when onions were heated in an oven, the heart’s heart-healthy nutrients completely disappeared after 30 minutes.


According to Dr. Julie Joffrion, bodybuilding nutritionist at All Inclusive Health, blueberries contain lots of antioxidants thanks to their high levels of polyphenols. However, according to scientists, processing blueberries by baking or cooking will significantly reduce polyphenol content.

Bell pepper

As you know, red bell peppers are an excellent source of vitamin C. According to nutrition experts, just eating 100g of red bell peppers can ensure the recommended amount of vitamin C. However, heat will damage vitamin C.


Kale contains glucosinolates. When glucosinolates comes in contact with the enzyme myrosinase, it will form isothiocyanates that have anti-inflammatory and anti-cancer properties. When cooked, heat disables myrosinase, so cooked kale does not have the same disease-prevention properties as raw kale salad.


Beets contain high levels of fiber, folate, vitamin C and manganese. Cooking depletes 25% of folate and other vitamins and minerals.


According to a 2010 study, fresh pineapple juice was more effective at reducing inflammation and spasms of colitis, compared to boiled pineapple juice. Researchers believe that fresh pineapple juice has higher levels of the enzyme bromelain, which helps fight inflammation.