1) What form of B12 is your sublingual and what's the dosage? Take this on an empty stomach for better absorption.

2) Your B complex would be best if it contained the bio active forms. Methly B12, P5P form of B6 and methyl folate. These forms do not require you body to convert them to a usable form.

3) Absorption issues
The liver can store approximately a five year supply of B12. So by the time your B12 shows up as being low to low-normal, you've probably had some issue going on for awhile. It's important to look at digestive health.

Off the top of my head, here are some reasons for low B12 absorption:
A - you lack intrinsic factor. Either due to damage to the lining of stomach or a possible auto-immune issue which destroys it.

B - Over growth of the wrong kind of gut bacteria, candida as well as h.pylori. The bad stuff eats up B12 so it gets to it before you do and compromise the gut lining.

C - You do not have sufficient HCI (stomach acid) to break down your food. People on acid reflux drugs will have an issue at some point. I know this sounds counter-intuitive, but alternative doctors will treat heart burn and acid reflux with HCI. You need B1, zinc and iodine to make stomach acid. If you don't have adequate stomach acid, you won't absorb zinc either.

D - Digestive enzymes produced by the pancreas are insufficient. Raw foods can help because they contain enzymes that will help break down food.

E - Celiacs disease/gluten intolerance will destroy the lining of gut and small intestine causing all kinds of issues as well as destroy the cell responsible for making intrinsic factor. And as you know, wheat and grain are inflammatory to many. Most people won't test positive for Celiac but benefit greatly when stopping gluten. It can a long time to heal from this.

F - Antibiotic use, aspirin, NSAIDs, Acid reflux drugs and alcohol abuse can mess things up.

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Regarding your IPAD/PHONE. The more common problem with these devices is related to structure. How you hold your neck and head can cause tension in the muscles which can lead to nerve issues. Pay attention to your posture.

You may want to try epson salt bath or hand soak. Espom salt contains magnesium and is very relaxing. There are also Magnesium creams you can try on the back of your neck/shoulders.

It can take months to restore your B12 and for your nerves to recover. So you are on the right track by cleaning up your diet and it's great that you have stopped smoking.

One last question....did they check your iron?