We all need 'nature’s Prozac’

For most of my adult life I have avoided doctors. They have been figures of fear for me since the day, aged eight, that I managed to convince my gentle and indulgent mother that I had such a bad stomach ache that I couldn’t go to school. It wasn’t the first occasion I had managed to pull off the “sick trick” – I was highly accomplished at faking symptoms that were not quite serious enough for a visit to the doctor’s surgery but allowed me a precious day at home.
But on this particular occasion I was so convincing that my alarmed mother called the doctor and, worried I would be found out, I so overdid the moans of agony when he examined me that an ambulance was called and I was rushed into hospital for an emergency – but quite unnecessary – appendectomy. As a result of that traumatic experience I have only ever gone near a doctor in the intervening years when I was pregnant or one of my three children was ill (or had pulled a “sick trick” on me).
Ironically it was severe stomach pain (real, not imagined) that forced me, for the first time in nearly 10 years, to see a doctor in late January. There were other symptoms: lethargy, loss of appetite and – something I had never suffered from before – depression. The doctor, a locum, diagnosed a possible kidney infection, and put me on antibiotics. But in the following weeks I developed unrelated infections, took two more courses of antibiotics and even underwent hospital X-rays as the locum sought to find the cause of what he called my “symptoms of a low immune system”.
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I had a severe vitamin D deficiency that had suppressed my immune system and was the likely cause of my depression. The cure was a capsule of pharmaceutical strength vitamin D (20,000 IU) to be taken once a week for three months.

Source  - Telegraph