The tale.
A friend had a faulty lap-top mains adaptor. It was one of these:-
From http://www.pchub.com/uph/laptop/46-33769-9191/Toshiba-Common-Item-Toshiba-AC-Adapter-Laptop.html |
I offered to fault-find it. I measured the output voltage with my multimeter.
The output voltage was 0V.
I felt the lead where it exited the connector. It didn't feel right, so I cut the connector off & stripped-off some insulation. Lo and behold, the inner conductor (it was co-axial cable) was broken. I prepared the conductors, tinned them, soldered them and powered the adaptor, with a sense of impending triumph.
The output voltage was 0V.
I tested the continuity from conductors to connector. That's when I discovered that there was a short-circuit between the inner and outer conductors. I snipped-off the connector and confirmed that it was the connector that was short-circuited, not the adaptor or cable. I fitted a replacement connector and powered the adaptor, with a sense of impending triumph.
The output voltage was 0V.
At this point, I decided that the adapter was Beyond Economic Repair and advised the friend to buy a new one, which subsequently worked perfectly.
So, how did the adapter get to have not one, not two but THREE faults on it? It turned out that the lead had been yanked sideways, which bent the connector. The friend had straightened the connector with pliers (!). This short-circuited the connector, resulting in an internal fuse blowing in the adapter. The friend then "jiggled" the connector in the socket, in a vain attempt to make it work. This broke the inner conductor of the co-axial cable.
The analogy.
Some health problems are multi-factorial. Fixing only one, but not all of the problems, results in not fixing the problem. So, if you try "A" and there's no improvement, either "A" isn't one of the problems, or "B", "C"......"Z" need fixing, too.
This post was inspired by Effects of 12 weeks high dose vitamin D3 treatment on insulin sensitivity, beta cell function, and metabolic markers in patients with type 2 diabetes and vitamin D insufficiency - a double-blind, randomized, placebo-controlled trial.
Taking an effective dose of Vitamin D3 for a reasonable length of time didn't make a significant difference to insulin sensitivity or beta cell function. It did for me, as my only problem was Vitamin D insufficiency. I got lucky.