Take a daily vitamin B12 supplement for 12 weeks to help your body

Back to Vitamin B12 Nutritional Deficiency trials

Recruiting

What is this trial?

Vegetarians are at risk for vitamin B12 deficiency because this nutrient is found mainly in animal products like meat and fish. This study is testing whether methylcobalamin, a natural form of vitamin B12, works better than cyanocobalamin, a synthetic form that's commonly used in supplements, at raising B12 levels in vegetarians who have low-normal B12 levels but no symptoms yet.

Vitamin B12 is essential for preventing serious health problems like anemia and nerve damage. Doctors want to know whether the natural form of this medication might be more effective than the standard synthetic form, especially for people following vegetarian diets who are at higher risk for B12 deficiency.

Do you qualify?

You likely qualify if…

you are 18 years or older and follow a vegetarian diet
you have vitamin B12 levels that are low-normal (between 148–221 pmol/L) but no symptoms of deficiency
you can read, write, and speak Catalan or Spanish
you have not taken vitamin B12 or folate supplements regularly for more than 2 months before joining
you are not pregnant, planning to become pregnant, or breastfeeding

You likely don't qualify if…

you have digestive problems like Crohn's disease, celiac disease, or inflammatory bowel disease
you have had stomach surgery, bariatric surgery, or other abdominal surgery that affects nutrient absorption
you are currently taking medications that interfere with B12 absorption, such as metformin or proton pump inhibitors
you have anemia, kidney disease, liver disease, diabetes, or heart disease
you smoke or have quit smoking in the last 6 months

What participation looks like

You will take one capsule by mouth every day for 12 weeks. About one-third of participants will receive methylcobalamin, one-third will receive cyanocobalamin, and one-third will receive a placebo (a capsule with no active ingredient). You'll visit the study center 8 times over the course of the trial for blood tests and health check-ins to see how your vitamin B12 levels change.

Comparing two forms of vitamin B12 supplements in vegetarians

What is this trial?

Do you qualify?

What participation looks like

Trial locations(2 sites)