Low iron hinders proper blood flow and metabolism, both of which are crucial for maintaining body temperature and feeling warm. Poor circulation especially causes the hands and feet to feel cold.

Low iron affects many aspects of the brain and mental health. Low iron levels can prevent parts of the brain from getting enough oxygen, which can manifest as anxiety, depression, and brain fog (inability to focus). Iron also regulates neurotransmitters, including those that influence mood, and myelination, which is how neurons connect to each other.

Low iron can cause restless legs syndrome (RLS), an uncomfortable condition that causes sensations in the leg and urges to move, especially at night. RLS may be caused by low dopamine levels resulting from low iron. RLS is typically worse at night because dopamine levels naturally fall throughout the day.