You can store it 21 days at room temperature under 25C (77F) or 28 days in a refrigerator at 2 to 8C (36 to 46F)
Quality and sourcing concerns
The mechanism that matters most for understanding the before and after timeline is angiogenesis
Although the vitamin sounds like a single vitamin, there are in fact eight B vitamins that are more of less prevalent in different foodstuffs, and regularly added as fortification to breads and cereals, for example - thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folate/folacin or folic acid (B9) and cobalamins (B12)
Storage above 25C reduces it further, to around 7 days
Even with a balanced diet, its common to miss key nutrients that play important roles in energy, immunity, bone health, and skin repair