Vitamin B12 deficiency is common in vegetarians or vegans as they consume very little animal protein. Stress can also bring down your Vitamin B12 levels. If you have been persistengly feeling tired and irritable without any specific reason or cold in your hand and feet, you may need to go for supplementation as vitamin B12 replenishes our entire body and energises us naturally. Here are some of the sneaky signs of Vitamin B12 deficiency, shared by nutritionist and gut health expert Smriti Kochar on her Instagram post.