What's the difference between eating food and adultery?

A question for the initial phase of starting meditation. To start meditation, it's important to know food first as per satipatthana. Materialistic food preserves cell-offspring reproduction inside body. In a way food helps in adultery. Whether we eat once a day or many times a day, no difference. Why to forcibly carry-on adultery within body at cellular level? Why not let the cells die naturally instead of allowing them to produce daughter cells by providing them required things. For this question, there is another subquery that can be considered, "what is natural?" "Is there anything as natural?" Various precepts might say adultery is natural, attraction of opp. identities(of any material) is natural but buddha gave a proper reason that can break this naturality. Is this merely a misguided term because natural is what it should be buddha's teachings but this teaching ends whole cycle and hence in the end, ends itself. Where is natural (infinite process of causes & effects) in here? So subquery can be ,Why word natural has contradictory meanings as per above 2 paragraphs? EDIT 1:: Understood subquery part, only 1st remains now. Impermanence is natural and nature. Natural is not infinite rather it is universally acceptable.