Can Vitamin B12 supplements prevent heart disease?

Vitamin B12 supplements have not reliably prevented heart disease, even though low blood levels are linked to higher risk. A review in Nutrition Journal explored Vitamin B12 Supplementation and heart health. It brought together lab work, large studies tracking people, and supplement trials. It covered different groups, rather than one new study of people taking supplements. The key finding is a gap between blood levels and health outcomes. Low Vitamin B12 was linked to higher heart disease risk. But raising levels with supplements did not consistently prevent major heart problems. Fixing a low level is not the same as proving heart protection. Treating a shortage still has established benefits for blood and nerve health. The clearest hint of stroke prevention came from taking several B vitamins together. This was strongest in places without required Folic Acid added to foods. Those findings do not show that B12 alone prevents strokes. The review also compared pills, shots, and products dissolved under the tongue. All raised blood levels, with no clear difference between methods. It described oral doses of 1,000–2,000 micrograms daily for shortages related to diet or age. Those doses concerned treating low levels, not proven heart protection. For BioSocial members, this gives bloodwork tracking a clearer purpose. A rising result can show that levels changed, without proving lower heart risk. Comparing starting levels, supplement form, dose, and follow-up dates can make community notes more useful. The authors also called for better evidence on the best blood-level range. Both low and very high levels were linked to higher death rates; that does not prove supplements caused those deaths. What changes have you seen in your bloodwork while tracking your supplement routine?