I only just saw your comment. If you can't burp anyway that makes the baking soda test a bit redundant. :)
Its also possible that you are taking too small doses of Vitamins, or ones that are in forms which the body cannot really use.
For example:
Zinc in the form of Picolinate has demonstrated actual higher levels in the body after longer use by peer reviewed studies, while other forms did not show any benefit at all.
Similar results were apparently observed with Copper Sebacate.
As for Vitamin C... ascorbic acid (and as crystals) seem to be effective, but mostly when taking it in higher doses such as 5 to 10 grams per day (dispersed throughout the day).
Also... Liposomal Vitamin C apparently demonstrated much higher effects compared to ascorbic acid... here's an extract:
This form of vitamin C is packaged inside nano-scale phospholipid spheres ("liposomes"), much like a cell membrane protects its contents. The lipid spheres protect the vitamin C from degradation by the environment and are absorbed more quickly into the bloodstream. Liposomes are also known to facilitate intracellular uptake of their contents, which can cause an added clinical impact when delivering something such as vitamin C. This form is supposed to be 5-10 fold more absorbable than straight ascorbic acid.
In addition... Vitamin D3 is the only viable supplement form of Vitamin D to take in measures of say 10 000 IU per day.
D2 is artificial form which is not readily usable by our body.
As for Selenium... Brazilian nuts contain highest concentrations of Selenium available through diet alone (I would imagine 3 or 4 of them daily would suffice).
In supplement form, I think that selenomethionine is the best potential form to take.
I suggest you try to find peer reviewed studies on the Vitamins you wish to supplement with to ascertain which forms have demonstrable effects by increasing levels in the body after longer use, as well which potencies are good.
The RDA for example is way too low for most Vitamins to have a measurable effect on the body (in reality you need much larger amounts).
I've had a Nissen Fundoplication surgery done to help with acid reflux. I normally don't burp. I can't even throw up. Would this surgery make the results of the baking soda test inaccurate?
Low stomach acid impairs the body's ability to absorb nutrients. Try the baking soda (sodium bicarbonate, not baking powder) test...
The following steps help to determine your stomach's acidity:
1. Perform this test first thing in the morning on an empty stomach (before
eating or drinking)
2. Dissolve ¼ teaspoon of baking soda into an 8 oz glass of cold water
3. Drink the solution and start timing
4. Record the time until you first burp up gas
5. Perform this test for 5 consecutive days (or longer) at the same time each day to give a better estimation of your stomach’s acidity
Time until first burp:
If you burp immediately and excessively your stomach acid level is probably too high
Under 2 min: indicates normal acidity
2 - 5 min: low normal acidity
Over 5 min: possible hypochlorhydria (low stomach acid)
No burping indicates possible achlorhydria (no stomach acid).
***
From the Ancient Minerals article Need More Magnesium? 10 Signs to Watch For...
"If you answer yes to any of the following questions, you may be at risk for low magnesium intake.
1. Do you drink carbonated beverages on a regular basis
2. Do you regularly eat pastries, cakes, desserts, candies or other sweet foods?
3. Do you experience a lot of stress in your life, or have you recently had a major medical procedure such as surgery?
4. Do you drink coffee, tea, or other caffeinated drinks daily?
5. Do you take a diuretic, heart medication, asthma medication, birth control pills or estrogen replacement therapy?
6. Do you drink more than seven alcoholic beverages per week?
7. Do you take calcium supplements without magnesium or calcium supplements with magnesium in less than a 1:1 ratio?
8. Do you experience any of the following:
Anxiety?
Times of hyperactivity?
Difficulty getting to sleep?
Difficulty staying asleep?
9. Do you experience any of the following:
Painful muscle spasms?
Muscle cramping?
Fibromyalgia?
Facial tics?
Eye twitches, or involuntary eye movements?
10. Did you answer yes to any of the above questions and are also age 55 or older?"