Why is it not recommended to eat vegetables grown in greenhouses?

1) plants grown in greenhouses contain an increased amount of nitrates, since the soil is enriched with manure or mineral nitrogen fertilizers;
2) nitrates disrupt the transport of oxygen and carbon dioxide in the human body and can cause the development of cancer.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.