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It has been estimated that vitamin B12 deficiency is present in about 20% of the elderly population. Nearly 40% of 3000 subjects in the Framingham Offspring study, were found to be B12 deficient.


Measuring MMA levels in the urine (and correcting for creatinine levels) helps reduce the chance that kidney issues are falsely increasing levels, which is not the case for blood MMA levels. This makes it easier to detect when it is even slightly elevated and a more sensitive test. It also doesn’t degrade for several weeks, so your sample will reach the lab in good time to be tested accurately.

Vegans and vegetarians are especially vulnerable to B12 deficiency because it is mainly found naturally in animal foods.

Pregnant women need more B12 to support their baby’s development.

Forty percent of people who take metformin for diabetes have B12 deficiency. This aggravates the neuropathy that is common in diabetes and can lead to serious problems.

People taking antacids or proton pump inhibitors (PPIs) for heartburn can also have B12 deficiency.

People who have had bariatric or other intestinal surgeries are more likely to have issues absorbing B12

Autoimmune diseases can also destroy the parietal cells in the stomach that make intrinsic factor (IF) causing a disease called “pernicious anemia”.

Elderly people can have a digestive system that doesn’t breakdown food as well, which can also contribute to a B12 deficiency.

Symptoms of B12 deficiency include lack of energy, weight loss, irritability, weak muscles and decreased appetite – view study
If left untreated, the symptoms of vitamin B12 deficiency tend to worsen and irreversible problems involving the nerves and brain may develop – view study
People at risk of B12 deficiency are those who have autoimmune disease, follow a vegetarian diet or take medications like Metformin – view study
Up to 40% of US adults could have a B12 deficiency – view study

EPISODE #14: Dr. Dariush Mozaffarian: Translating Nutrition Science into Practice
EPISODE #13: Dr. Jing Kang: How the Fat-1 Mouse Creates Omega-3 from Omega-6
EPISODE #12 – Part 2: Is DHA Essential? – Dr. Norm Salem

