What Causes Lack of B?
                                
                                
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                                    3 min read                                
                            
                                Studies suggest that up to 20% of people over the age of 60 in the US and UK are deficient in vitamin B12 alone, but a lack of any B-complex vitamin can be caused by various factors. These essential, water-soluble nutrients play a critical role in energy production, nervous system function, and DNA synthesis.