10 Things You Need to Know About B12

5. Too Much Folate Can Hide a B12 Deficiency

The percentage of people with B12 deficiencies may seem strangely uncertain. This is because other nutrients, such as folic acid, can mask vitamin B12 deficiencies until they advance. Large quantities of folic acid can help correct megaloblastic anemia, a condition caused by B12 deficiency. However, even folate cannot reduce the cognitive decline and neurological damage that a lack of B12 will eventually cause. Some studies suggest folate may even worsen the symptoms. Healthy adults should not have more than 1,000 mcg of folic acid per day.