This mineral has an essential role in helping to keep your body energised. Iron is involved in the transport of oxygen in the blood, helping to deliver the oxygen required for your muscles to function efficiently. It also has an important role in keeping your immune system healthy. Low levels of iron within the body may lead to fatigue, tiredness, decreased immune function and small, pale red blood cells. Females are most risk of having low iron levels, particularly those who are menstruating, pregnant or involved in heavy activity, as iron can be lost through blood loss and sweating. The recommended RDI of iron is 8mg per day for men, 18mg per day for women. This can be obtained from high iron sources such as meat, seafood, spinach, broccoli and peas. When eaten in combination with foods that contain vitamin C, iron absorption is increased. If you suspect you are low in iron, see your doctor before undertaking any supplementation, as consuming too much iron can be harmful.