Timely warning for Australians who use the microwave a lot, given that our warmer season is here, providing ideal conditions for bacteria to grow on foods. Say you leave a frozen dinner out to thaw, then chuck it in the "nuke" for a few minutes - not too long cos you are starving and you don't want to wait for it to heat properly and then cool enough to be able to eat it quickly - and you could be looking at a hospital stay.
Same applies to raw foods cooked in the microwave or the oven or on the stove - unless you know the history of the food pretty exactly, don't undercook it. Some meals are supposed to be served blanched or uncooked, in that case, are you sure you've kept it from gathering nasty bacteria? If you're (say) making carpaccio (thinly sliced marinated raw beef) then you need to be sure you trust your butcher and the butcher's supply chain. And you should have stored the beef at the right temperature. Away from other foods to prevent possible contamination.
Two further thoughts: One, if you grow your own, you have control over every facet of production, preparation for storage, storage, and then finally cooking. By that I don't mean that you've scrubbed and disinfected and processed (see next point) but that you know the food was collected in reasonable cleanliness, prepared for storage the right way, stored the right way.
Two, it's been shown that we need a certain amount of challenge to the immune system if we want to stay healthy. Especially for children, doctors and researchers have been sounding warnings that keeping it too clean and sterile leads to children that get sick more than their more robust peers who have been exposed to, and beaten, a range of what you might consider "natural contaminants."
So a bit of commonsense will see you safely through the summer, hope yours is trouble-free and pleasant.