Why Dr. Greger Recommends Cyanocobalamin
Based on his review of peer-reviewed scientific studies, Dr. Michael Greger explicitly recommends cyanocobalamin for most people seeking a vitamin B12 supplement. He explains that while cyanocobalamin is a synthetic form, it is converted by the body into the active B12 forms needed for biological function, such as methylcobalamin and adenosylcobalamin.
His rationale for favoring cyanocobalamin includes:
- Superior stability: Cyanocobalamin is more stable than other forms, particularly when exposed to light, making it a reliable option.
- Cost-effectiveness: It is often the most cost-effective and widely available form of the supplement, making it accessible to a wider population.
- Extensive research: The vast majority of studies on B12 supplementation have been conducted using cyanocobalamin, demonstrating its effectiveness in addressing deficiencies.
- Reliable conversion: For most healthy individuals, the body effectively converts cyanocobalamin into the necessary active forms.
Exceptions to the Rule
There are a few specific circumstances where an alternative to cyanocobalamin might be preferable. For example, Dr. Greger notes that methylcobalamin may be a better option for those with impaired kidney function. Other forms might also be considered in specific cases like heavy smoking.
Dr. Greger's B12 Supplementation Recommendations
Dr. Greger provides different supplementation options based on individual needs and lifestyle preferences. Note that these are specific to cyanocobalamin supplementation:
For Adults Under 65 (Vegan, Vegetarian, or Flexitarian):
- Weekly Option: A weekly supplement of cyanocobalamin is one approach to consider.
- Daily Option: A daily supplement of cyanocobalamin is another potential option.
For Adults Over 65:
- Due to age-related decline in absorption, Dr. Greger advises a daily approach to cyanocobalamin supplementation.
For Pregnant and Breastfeeding Individuals:
- A daily or more frequent supplementation approach is suggested.
For Children:
- Specific recommendations are provided for various age groups, typically starting after weaning and increasing with age.
Optimal Administration
To potentially maximize absorption, Dr. Greger suggests taking B12 supplements in a chewable, sublingual (dissolving under the tongue), or liquid form. This is especially important as we age and gastric acid production declines. He also recommends taking the supplement as a stand-alone, preferably on an empty stomach, to avoid interference from other vitamins and minerals commonly found in multivitamins.
Cyanocobalamin vs. Methylcobalamin: A Comparison
To understand the difference between the two most common B12 supplement forms, here is a comparison based on the available research Dr. Greger references:
| Feature | Cyanocobalamin | Methylcobalamin |
|---|---|---|
| Source | Synthetic (artificially produced) | Natural (found in foods like meat and eggs) |
| Stability | Highly stable; less prone to degradation from light | Less stable and more susceptible to light destruction |
| Cost | Less expensive and often more cost-effective | Typically more expensive |
| Research | More extensively studied and shown to be effective | Less research evidence, with mixed results on efficacy |
| Absorption | Converted in the body; some studies show potentially better absorption | Potentially higher retention, but may require a different approach to dosing |
| Use Case | General supplementation for most people on plant-based diets | Potential benefit for those with kidney issues or high cyanide exposure |
Fortified Foods as an Alternative
For those who prefer not to take supplements, B12 can be obtained from fortified foods such as nutritional yeast, plant-based milks, and breakfast cereals. However, this method requires consistent effort and careful label reading. It typically involves consuming fortified foods multiple times daily. For many, this is considered a less reliable and potentially more complicated approach compared to a simple supplement.
Conclusion
Dr. Michael Greger's recommendation for cyanocobalamin is rooted in its proven effectiveness, high stability, and cost based on the available scientific literature. For the majority of people, especially those following a plant-based diet, cyanocobalamin offers a simple, reliable, and often affordable way to meet their B12 needs. By considering his specific recommendations and opting for sublingual or chewable forms, individuals can work towards ensuring proper B12 status. For further reading on the science, visit the official NutritionFacts.org website.
