Food is our sustenance, for life and health. Traditional thought is that food is our medicine, and we should choose it carefully, and that all illness is due to "bad" foods we ingest.
Food comes in various forms, colours and smells and by listening to our body we will know what is good for us. Vibrant colours and smells will attract animals, which eat and then through their excrements will sow the seeds for renewal of the plant species.
Foods are primarily in plant form, but some animals eat other species for their survival.