Selenium
Some search terms matched…t enzymes work, but a GPX variant does not prove a selenium deficiency. Review food, multivitamins, thyroid products and separate supplements together. Taking too much selenium can be harmful.
How supplementation is approached
Dr. Purser co…
Shiitake
Some search terms matched…APA result. A cell-response finding is not a diagnosis of a deficiency in this botanical or compound.
Shiitake mushrooms used as food differ from concentrated mushroom extracts.
What symptoms can—and cannot—tell you
There is no established…
Strontium
Some search terms matched…oms can—and cannot—tell you
There is no established dietary deficiency syndrome for this specific botanical or compound. Symptoms are not evidence that you need this supplement.
Food sources
Trace amounts occur in foods and water; there is …
Sulforaphane
Some search terms matched…APA result. A cell-response finding is not a diagnosis of a deficiency in this botanical or compound.
Broccoli-derived preparations may supply sulforaphane or its precursor glucoraphanin, sometimes with myrosinase. These labels are not int…
L-Threonine
Some search terms matched…e or a laboratory finding is not automatically a standalone deficiency diagnosis. Assess overall protein intake, absorption and the clinical setting with a qualified clinician.
Food sources
Protein foods such as eggs, fish, poultry, meat, d…
Turmeric
Some search terms matched…APA result. A cell-response finding is not a diagnosis of a deficiency in this botanical or compound.
Turmeric as a spice differs from concentrated curcumin extracts, especially formulas with absorption-enhancing ingredients.
What symptoms…
L-Valine
Some search terms matched…e or a laboratory finding is not automatically a standalone deficiency diagnosis. Assess overall protein intake, absorption and the clinical setting with a qualified clinician.
Food sources
Protein foods such as eggs, fish, poultry, meat, d…
Vanadium
Some search terms matched…oms can—and cannot—tell you
There is no established dietary deficiency syndrome for this specific botanical or compound. Symptoms are not evidence that you need this supplement.
Food sources
Trace amounts occur in foods such as mushrooms, g…
Vitamin A
Some search terms matched…ts vision, immune function and tissue development.
Possible deficiency symptoms
Deficiency can cause night blindness and eye-surface damage.
How supplementation is approached
Distinguish preformed vitamin A from beta-carotene and review exi…
Vitamin B1 (Thiamine)
Some search terms matched…od into usable energy and supports nerve function.
Possible deficiency symptoms
Severe deficiency can cause weakness, nerve problems, confusion and heart problems.
How supplementation is approached
Review thiamine within food intake, digest…
Vitamin B2 (Riboflavin)
Some search terms matched…may matter, but an MTHFR result does not prove a riboflavin deficiency or tell you a dose. Include any B-complex or multivitamin you already take when you review your options.
How supplementation is approached
Dr. Purser connects riboflavin…
Vitamin C (Ascorbic Acid)
Some search terms matched…tioxidant activity and absorption of nonheme iron.
Possible deficiency symptoms
Severe deficiency can cause bleeding gums, easy bruising, poor wound healing and fatigue.
How supplementation is approached
Review vitamin C intake, the actual …
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