I have already explained that one particular head of broccoli does not necessarily equal another head of broccoli; the nutritional composition of apparently identical foods can be highly variable. Not only do different samples of the same type of food differ wildly in protein content, amino acid ratios and mineral content, their vitamin and vitamin-like substances also vary according to soil fertility and the variety grown. These days, food crop varieties are bred for yield and other commercial considerations, such as shipability, storage life, and ease of processing. In pre-industrial times when each family propagated its own unique open-pollinated varieties, a natural selection process for healthy outcomes prevailed. If the family's particular, unique varieties carried genes for highly nutritious food, and if the family's land was fertile enough to allow those genes to manifest, and if the family kept up its land's fertility by wise management, their children tended to survive the gauntlet of childhood illness and lived to propagate the family's varieties and continue the family name. Thus, over time, human food cultivars were selected for their nutritional content. But not any longer! These days, farming technology with its focus on bulk yield and profit, degrades the nutritional content of our entire food supply. Even commercial organically grown food is no better in this respect. Sub-clinical, life-long, vitamin and mineral deficiencies contribute to the onset of disease; the malnourished body becomes increasingly enervated, beginning the process of disease. Vitamin supplements can increase the body's vital force, reversing to a degree the natural tendency towards degeneration. In fact, some medical gerontologists theorize that by using vitamins it might be possible to restore human life span to its genetically programmed 115 years without doing anything else about increasing nutrition from our degraded foods or paying much attention to dietary indiscretions. Knowing what I do about toxemia's effects I doubt vitamins can allow us to totally ignore what we eat, though supplements can certainly help. More than degraded nutritional content of food prompts a thinking person to use food supplements. Our bodies and spirits are constantly assaulted and insulted by modern life in ways our genetics never intended us to deal with. Today the entire environment is mildly toxic. Air is polluted; water is polluted; our food supply contains traces of highly poisonous artificial molecules that our bodies have no natural ability to process and eliminate. Our cities and work places are full of loud, shocking noises that trigger frequent adrenaline rushes and other stress adaptations. Our work places are full of psychological stresses that humans never had to deal with before.