Over time, peripheral nerve damage resulting from vitamin B-12 deficiency can lead to movement problems, said Medical News Today. The health site continued: “Numbness in the feet and limbs may make it hard for a person to walk without support. “They may also experience muscle weakness and diminished reflexes.” Vitamin B12 deficiency: The lesser-known warning found in the way you are walking (Image: Getty Images) Vitamin B12 deficiency symptoms can cause damage to the nervous system which affects the way a person’s legs move and the way they walk. Lacking in the vitamin can therefore impede a person’s overall balance and could even make them prone to falling.