9 best vitamins for sleep

Iron helps transport oxygen throughout your body, which is why a deficiency can leave you feeling fatigued. Remember how Popeye eats spinach and becomes strong and powerful? Yep, spinach is packed with iron. An iron deficiency has been linked to restless leg syndrome, a condition that causes uncomfortable sensations in the legs and an urge to move the legs when falling asleep. Dr Levitan and her co-author, endocrinologist Dr Romy Block, say iron deficiency is common – particularly among women. If you have iron-deficiency anaemia, you may need to take a supplement.