I call it "so-called" cold and flu season due to the reality that sickness shouldn't increase during this time if proper care is taken to maintain good health! For information on remedies to support the system during increased need:
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Be sure you are not deficient in Vitamin D. It is not expensive to to test for. Whole food sources of Vitamin D come from eggs, fresh salmon, sardines and shiitake mushrooms. Dry, flaky skin can be an indication of a need for more Omega 3 fats - also a great source of vitamin D from Anchovies and supplements such as krill, tuna, or cod liver oil.
Friendly bacteria - what consumers fail to realize is their scented antibacterial soaps carry the high price tag of suppressing the immune system. "Cleaning up" the germs also means destroying the good bacteria that combat the bad and help protect us from disease.