Common knowledge?

We’ve talked over the past two Minutes about critical thinking. The webinar that prompted these musings adds one more concept: knowledge illusion. Sometimes we talk so much about a subject that we think we know more than we do. Or more correctly, we think we know more facts than we do.

A perfect illustration occurred last week. Taking a garden tour with a Master Gardener we learned more than we could ever remember about self-seeding plants, pruning, varietals of basil…she was an expert in her subject matter. Then, she said, if we would all get 10 minutes of sunshine daily, we would meet our vitamin D requirement.

It probably IS common knowledge that vitamin D is called the sunshine vitamin. Do we know any other facts? A few of us will remember that a chemical in the skin (a type of cholesterol) is converted by UV B radiation which then requires work by the liver, then kidneys to become an active form of vitamin D in the body.

What was missing from this gardener’s confident admonition that 10 minutes is all we need? Before prescribing 10 minutes/day we must know:

  • your latitude
  • presence or lack of air pollution
  • what clothing you’re wearing – fabric content and color
  • presence or absence of sunscreen
  • season of year (in your hemisphere)
  • time of day
  • is the sun is passing through a glass or other compound
  • your skin color

The gardener had knowledge illusion. She spoke confidently and authoritatively about vitamin D, but her “expertise” was not in nutrition. I’m not certain our group was listening that carefully but it reminded me of all the times someone offers a nutrition “fact” with a kernel of truth amid a melange of misinformation – it can potentially be  harmful.

So, I thought we’d take a few of our upcoming Minutes to look at some nutrition basics for some knowledge WITHOUT the illusion to be well,



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