@mononoke - I think dosing for sodium bicarbonate is different for each person so I can't answer how often you can take it, you might try a search on the board for this or do a separate post. I've taken it 2 x a day with no problem, some people have taken more.
I try to take it at least 30 mins. before eating and at least an hour after eating.
Re taking vitamins and minerals - yeah, there's testing like Nutreval which is very good if you can get it done. It is pricey and it can be hard to find a doctor who will do it. I don't know if Nutreval is available in the UK, would have to ask other UK members. There may be equivalent UK testing.
I had nutreval testing done several years ago and it showed a severe B6 deficiency. I'd been taking a B complex forever but it wasn't enough. So I added in B6 (P-5-P) and had a boost in energy.
Hair analysis always showed my B12 as almost non-existent despite high blood levels. Apparently I (and many others with ME/CFS) have difficulty metabolizing B12. So the high blood levels were meaningless - they were high because of my supplement but did not mean I had to much B12, rather, the opposite - that I was having trouble using the B12 I was taking. So I take high dose B12 (5000 mcg. liquid (sublingual) methylobalamin) and do well with it
I experimented on my self with methylfolate. It boosted my energy for a few days and then caused my potassium to tank from refeeding syndrome. My chief symptom was severe fatigue (after the energy boost). I started taking potassium (titrated up to 1000 mg a day) and the severe fatigue went away.
I'd read that thiamine helped boost energy so just tried it. And it did boost my energy very nicely, for a day or 2, and then severe fatigue hit. But it was different than the fatigue with low potassium, plus potassium didn't fix it. Because i'd read about refeeding syndrome, I knew that low phosphorous - hypophosphatemia - was the hallmark of refeeding syndrome, and so theorized that my phosphorous had tanked, and it had. I determined this by drinking several glasses of kefir - high in phosphorous - and within several hours that fatigue started to abate. I've since learned I need to supplement with phosphorous on a regular basis.
Ideally one would have testing for all of this. But blood testing alone is often inadequate. e.g., one can have low potassium in the cells despite normal blood work, sort of like the B12. I've had to do a lot of experimenting on my own.
I recommend trying to find what sort of nutritional testing is available where you live and what others in the UK have done, and then educating yourself as much as possible if you do decide to do any experimenting.
As to whether you're absorbing nutrients, many of us have low stomach acid. I do. and have to take betaine with pepsin with meals. It has helped my digestion so much. A simple test is dissolve 1/4 to 1/2 teaspoon of baking soda in 8 ounces of water, drink on an empty stomach, and see if you burn within a few minutes. If you don't, it may be an indication of low stomach acid.
So the supplements you were taking may have been good for you, but may not have been enough or you may not have been absorbing them properly. I take a B complex plus extra B1, B6 (P-5-P), folate and B12, as well as a ton of other stuff.
