Vitamin B12: Hidden Deficiency?

According to the American Journal of Clinical Nutrition, approximately 6% of individuals over the age of 60 in the United Kingdom and the United States suffer from vitamin B12 deficiency. Researchers state that this vitamin deficiency is far more common in populations of less developed countries, beginning early in life and persisting throughout.

Vitamin B12 deficiency can cause a wide variety of symptoms that initially develop gradually and may worsen if the condition is left untreated.

Vitamin B12 deficiency can be diagnosed based on physical symptoms and also through a blood test. It is crucial for it to be diagnosed and for a replenishment method to be found as quickly as possible, because, although many symptoms improve with treatment, some problems caused by the condition can be irreversible.

Unfortunately, vitamin B12 deficiency is relatively common, especially among older populations. A national health and nutrition survey in the United States showed that 3.2% of adults over 50 years old have very low levels of the vitamin, and 20% already exhibit symptoms of the deficiency.

We find Vitamin B12 ONLY in meats, milk, cheeses, eggs, and supplements. The B12 found in algae and fermented foods is different from what we need for our metabolism.

Approximately 50% of vegetarians have vitamin B12 deficiency; however, about 40% of non-vegetarians also have vitamin B12 deficiency, suggesting that factors influencing the absorption of this nutrient are likely involved in this inadequacy.

Symptoms are quite non-specific, which makes clinical diagnosis (based on signs and symptoms) difficult, necessitating evaluation through laboratory tests to rule out other problems with similar symptoms.

The earliest symptom I have observed in patients I treat are complaints of tingling in the legs after only a few minutes of sitting with crossed legs. Similarly, complaints of reduced cognitive activity (concentration, memory, and attention) are the norm. In B12 deficiency, there is difficulty maintaining intellectual activity comfortably.

It can manifest with altered sensation in the feet and legs, reduced proprioception (the individual has difficulty adequately perceiving their own body), and psychiatric symptoms.

Anemia due to B12 deficiency can occur, but it is less common than the neurological symptoms mentioned above.

In the past, approximately 250 apparently normal individuals were recruited, and their blood was collected. Of the values found, 95% of them were between 200 to 900 pg/mL of vitamin B12. Thus, this value was used as the normal range.

2) The range is very broad (200 to 900 pg/mL), which already suggests an exaggerated flexibility in data analysis. With different blood markers, we verify that being within this normal range does not mean having optimal blood levels. Below, we will see the levels at which it should be maintained from our preventive perspective.

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