Less iron = less energy

Iron is an essential mineral for human health. It’s an integral part of haemoglobin, the oxygen-carrying portion of red blood cells, and the oxygen-storing molecule, myoglobin, found in muscles. Iron also helps the body make ATP (adenosine triphosphate), the energy source for most metabolic functions.

Low iron levels can result in anaemia, a condition characterised by a decrease in the number of red blood cells and low haemoglobin and hematocrit levels. With fewer red blood cells circulating and less haemoglobin available, less oxygen is available for the brain and other organs and tissues.

People with iron-deficiency anaemia may complain of

• fatigue,
• shortness of breath,
• impaired concentration, and
• poor immune function.

Sleepy mystery solved

Fatigue is one of the first symptoms that shows up in people with iron-deficiency anaemia, but people who have low iron levels without overt anaemia may also become excessively tired.

The study assessed the effects of iron supplementation in nonanaemic 18-to-53-year-old women with borderline-low iron stores who complained of fatigue. The women were assigned to take 80 mg of elemental iron or placebo for 12 weeks.

• Fatigue declined by almost 50% in women who took the iron supplement, compared with a 29% decline in the placebo group.
• Iron supplementation significantly increased iron stores as well as haemoglobin and hematocrit levels compared with placebo.

“Iron deficiency may be an under-recognised cause of fatigue in women of child-bearing age,” commented the researchers, pointing out that identifying iron deficiency as a potential cause of fatigue may “reduce the unnecessary use of health care resources, including inappropriate pharmacologic treatments.”

Making iron work for you

Low iron levels can stem from two main sources—blood loss and not getting enough in the diet. The most common cause of iron-deficiency anaemia in premenopausal women is excessive menstrual blood loss. Iron deficiency can also be a sign of other more serious conditions. A doctor can help pinpoint the source of the problem—and while eating an iron-rich diet (see tips that follow) is good for most people, it’s important not to supplement iron unless you know you are deficient as a small number of people may not be able to effectively eliminate iron, resulting in a toxic build up of the mineral.

• Eat some C. Vitamin C, that is. Eating iron-containing foods with those that are rich in vitamin C, like peppers, strawberries, oranges, papaya, broccoli, and kiwi, enhances iron absorption.
• Cook in cast iron. Cooking acidic foods like tomatoes in cast iron can increase the iron content of your meal.
• Go paleo. Animal foods—including beef, poultry, venison, fish, oysters, and buffalo—contain the most absorbable form of iron, called haem iron.
• Eat your vegetables. Good plant-based sources of iron include beans, leafy greens, lentils, dried fruit, and blackstrap molasses.

(CMAJ 2012. doi:10.1503/cmaj.110950)