I know we have discussed microwaved food before.
I have searched for the thread and can't find it.
In recent months I have been learning about vitamins and their functions in body metabolism.
I have come across this Japanese study and thought you might need to know.
Effects of microwave heating on the loss of vitamin B12 in foods
Vitamin B-12 is naturally found in meat (especially liver and shellfish), milk and eggs,
and is seriously affected by microwave cooking, and so the nutritional value of that food is reduced.
The value is reduced by 30 - 40%
Vitamin B12 explained in Wikipedia-
Vitamin B-12 is a water soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. It is one of the eight B vitamins. It is normally involved in the metabolism of every cell of the body, especially affecting DNA synthesis and regulation, but also fatty acid synthesis and energy production.
Vitamin B12 is found in foods that come from animals, including fish, meat, poultry, eggs, milk, and milk products.
One half chicken breast, provides some .3 µg per serving or 6.0% of your daily value, (DV) 3 ounces of beef, 2.4 µg, or 40% of your DV, one slice of liver 47.9 µg or 780% of your DV, and 3 ounces of Molluscs 84.1 µg, or 1,400 % of your DV, while one egg provides .6 µg or 10% of your DV.
Vegans may have a challenge to ensure that they meet their daily allowance for B-12.
It is the most difficult vitamin for your body to extract from food, so to waste some by microwaving is not a wise practice.