Vitamin B12 levels in the blood can vary due to several factors tied to supplementation and absorption. Here’s a breakdown of how that works:

1. Absorption Mechanism: Vitamin B12 is absorbed in the small intestine after binding with a protein called intrinsic factor, produced in the stomach¹. When you take supplements, B12 is already in its free form, which removes the initial binding step and allows for easier absorption in the gut².

2. Supplementation and Blood Levels: When you consume B12 supplements, your blood levels may increase quickly because the vitamin can bypass some absorption steps required for B12 from food sources. This rapid absorption can lead to elevated vitamin B12 levels in the bloodstream, which can be detected in tests even long after you stop taking the supplements³.

3. False Reading Concept: The idea of a "false reading" typically refers to cases where B12 blood levels appear normal or high despite a functional deficiency (ineffective cellular utilization due to issues with intrinsic factor, for example)³. Supplements can create an impression of adequate levels, which might not reflect the tissue level or metabolic activity of B12.

4. Persistent Elevated Levels: If your B12 levels stay high after stopping supplements, it may indicate that your body has absorbed and retained the vitamin effectively. Additionally, stores of B12 in the liver can last for years, and diet can continue to maintain elevated levels in conjunction with past supplementation².

5. Interpreting Your Results: It’s encouraging that after discontinuation of supplements for a month, your B12 levels remain in the 700s, suggesting effective absorption and body stores. It's important to consider whether your levels are clinically appropriate by consulting a healthcare professional, as they can be affected by many factors, including diet and individual metabolic needs³.

If the high levels are still concerning or if you have symptoms related to vitamin B12 metabolism, other tests (like methylmalonic acid levels) can provide additional insights into true vitamin B12 status⁴.

Footnotes

1. NHS - Vitamin B12 or folate deficiency causes ↩

2. Harvard - Vitamin B12 ↩ ↩²

3. NIH - Office of Dietary Supplements: Vitamin B12 ↩ ↩² ↩³

4. Harvard - Better markers of B12 activity ↩

Vitamin B12 itself is not typically directly associated with weight gain. However, there are a few potential mechanisms and scenarios where changes in vitamin B12 status might be related to body weight:

1. Improved Metabolism and Energy Levels: Vitamin B12 is crucial for energy metabolism and the proper functioning of nerve cells. If you were deficient in B12, you might have experienced fatigue and a slower metabolism¹. Supplementing and alleviating the deficiency could improve energy levels and metabolic functions, potentially affecting appetite and dietary habits¹.

2. Changes in Appetite: With improved B12 levels, you might experience an increased appetite if you had previously suffered from fatigue or other deficiency symptoms that affected your desire or ability to eat. This could indirectly lead to weight changes if not balanced with physical activity².

3. Improved Nutrient Absorption: If your B12 levels were low, your overall gut health and nutrient absorption might have been compromised, potentially affecting your weight. Restoring B12 to normal levels can aid in the better absorption of nutrients³.

4. Underlying Health Conditions: If you've gained weight alongside B12 supplementation, it might be related to underlying health conditions or dietary habits rather than the supplementation itself. B12 is generally not directly linked to weight gain⁴.

It's important to consider other dietary and lifestyle factors, as well as consult with a healthcare professional for a comprehensive evaluation. This will help determine if additional dietary changes or health conditions might be influencing weight gain.

Footnotes

1. Harvard - Vitamin B12 ↩ ↩²

2. NIH - Office of Dietary Supplements: Vitamin B12 ↩

3. [NHS - Vitamin B12 or folate deficiency anaemia][source 1] ↩

4. Harvard - Better markers of B12 activity ↩

When you talk about "active" forms of Vitamin B12, you're likely referring to methylcobalamin and adenosylcobalamin, which are used by the body directly without the need for conversion. Here's how these forms interact with your body's systems and the notion of "false activation":

1. Active Forms: Methylcobalamin and adenosylcobalamin are coenzyme forms of Vitamin B12 that are biologically active and do not require conversion to be used by the body¹. They bypass the conversion process needed for cyanocobalamin, another form commonly found in supplements.

2. "False Activation" Concept: The term "false activation" in this context typically refers to situations where blood levels of B12 appear sufficient due to supplementation but do not reflect adequate tissue utilization or functional availability. This can occur if there are underlying absorption issues such as with intrinsic factor deficiencies².

3. Assessment of B12 Status: Using active forms like methylcobalamin may lead to elevated serum B12 levels, but this does not always equate to functional sufficiency at the cellular level. Testing for metabolites such as methylmalonic acid (MMA) and homocysteine is recommended to assess the true functional status of Vitamin B12 in the body³. Elevated levels of MMA and homocysteine can indicate a functional B12 deficiency even if serum B12 levels are normal.

4. Benefits of Active Forms: For individuals with certain medical conditions or absorption issues, using active forms might be beneficial as they are absorbed directly and utilized promptly by the cells. However, the perception of "false activation" will still depend on whether the cellular pathways that require B12 are functioning correctly⁴.

Thus, while taking active forms of B12 can be more effective in certain scenarios, it doesn't necessarily eliminate the issue of "false activation" if the underlying cause of deficiency is related to absorption at a different point in metabolism or cellular use.

Footnotes

1. Harvard - Vitamin B12 ↩

2. NIH - Office of Dietary Supplements: Vitamin B12 ↩

3. Harvard - Better markers of B12 activity ↩

4. NHS - Vitamin B12 or folate deficiency anaemia ↩