Does Mark Hyman recommend Vitamin B12?
Mark Hyman recommends Vitamin B12 in some contexts, but has also raised cautions.
Published research rates it strong evidence. Of Mark Hyman's 26 tracked claims, 0 are supported or partially supported by studies on PubMed.
Evidence last reviewed May 2026
Mark Hyman on Vitamin B12 — 26 claims
“the ones that are really causing Havoc are you know deficiencies and you know the methylation nutrient it's like the B vitamins folate B6 B12 deficiencies”
Deficiencies in methylation nutrients including B12, folate, and B6 are among the most common and impactful nutrient deficiencies causing problems in the country.
“We check your level of B vitamins like homoyine and methylonic acid which measure B12, folate, B6 effectiveness.”
Methylmalonic acid and homocysteine can be tested to measure the effectiveness of B12, folate, and B6, as part of a 'test, don't guess' approach to identifying nutrient deficiencies.
“a B12 shot and they're on a different path”
Giving a B12 shot to patients with low-normal B12 levels who have severe depression can put them on a different (improved) path.
“the ones that are really causing Havoc are you know deficiencies and you know the methylation nutrient it's like the B vitamins folate B6 B12 deficiencies”
Deficiencies in methylation nutrients including B12, folate, and B6 are among the most common and impactful nutrient deficiencies causing problems in the country.
“We check your level of B vitamins like homoyine and methylonic acid which measure B12, folate, B6 effectiveness.”
Methylmalonic acid and homocysteine can be tested to measure the effectiveness of B12, folate, and B6, as part of a 'test, don't guess' approach to identifying nutrient deficiencies.
“a B12 shot and they're on a different path”
Giving a B12 shot to patients with low-normal B12 levels who have severe depression can put them on a different (improved) path.
“you want to make sure that you reduce your uh drugs if you can or switch to different drugs or are not that are not depleting the the nutrients or that you actually take the nutrients as a replacement”
If taking nutrient-depleting drugs such as acid blockers, patients should either switch drugs or take the depleted nutrients (including B12) as replacement.
“you want to make sure that you reduce your uh drugs if you can or switch to different drugs or are not that are not depleting the the nutrients or that you actually take the nutrients as a replacement”
If taking nutrient-depleting drugs such as acid blockers, patients should either switch drugs or take the depleted nutrients (including B12) as replacement.
“some of the nutritional deficiencies that are pretty common that any family doc could do would be vitamin B12 and d”
Vitamin B12 deficiency is a common nutritional deficiency seen in patients with depression that is modifiable.
“some of the nutritional deficiencies that are pretty common that any family doc could do would be vitamin B12 and d”
Vitamin B12 deficiency is a common nutritional deficiency seen in patients with depression that is modifiable.
“if you taking an acid blocking drug you're going to prevent B12 absorption and even magnesium and and zinc absorption”
Acid-blocking drugs prevent B12 absorption.
“It inhibits B12 absorption which is critical for so many functions that can cause depression, dementia, neurologic issues. People don't know this”
Long-term use of proton pump inhibitors (PPIs) inhibits B12 absorption, which is critical for many functions, and can cause depression, dementia, and neurologic issues.
“It inhibits B12 absorption which is critical for so many functions that can cause depression, dementia, neurologic issues. People don't know this”
Long-term use of proton pump inhibitors (PPIs) inhibits B12 absorption, which is critical for many functions, and can cause depression, dementia, and neurologic issues.
“if you taking an acid blocking drug you're going to prevent B12 absorption and even magnesium and and zinc absorption”
Acid-blocking drugs prevent B12 absorption.
“vitamin B12 is a pet peeve of mind because our normal range the lab slips might say 220 to 1100 and nobody feels well with a level of 220 so times we've treated people with severe depression that we're told by their PCP they have normal B12”
The conventional lab normal range for B12 (220–1100) is misleading because nobody feels well at a level of 220, and patients with severe depression have been told they have normal B12 when they do not.
“vitamin B12 is a pet peeve of mind because our normal range the lab slips might say 220 to 1100 and nobody feels well with a level of 220 so times we've treated people with severe depression that we're told by their PCP they have normal B12”
The conventional lab normal range for B12 (220–1100) is misleading because nobody feels well at a level of 220, and patients with severe depression have been told they have normal B12 when they do not.
“We check your level of B vitamins like homoyine and methylonic acid which measure B12, folate, B6 effectiveness.”
Measuring methylmalonic acid and homocysteine can assess B12 effectiveness as part of a functional medicine workup.
“rather than just taking a drug to suppress stomach acid which we desperately need to digest our food to absorb minerals to absorb B12 to digest protein”
Stomach acid is needed to absorb B12, and drugs that suppress stomach acid interfere with this absorption.
“rather than just taking a drug to suppress stomach acid which we desperately need to digest our food to absorb minerals to absorb B12 to digest protein”
Stomach acid is needed to absorb B12, and drugs that suppress stomach acid interfere with this absorption.
“We check your level of B vitamins like homoyine and methylonic acid which measure B12, folate, B6 effectiveness.”
Measuring methylmalonic acid and homocysteine can assess B12 effectiveness as part of a functional medicine workup.
Other supplements Mark Hyman discusses
Claims are extracted from publicly available podcasts and videos, attributed to their source, and compared against PubMed research. This is educational information only — consult a healthcare provider before starting any supplement.
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