(NewsUSA) - Iron deficiency, according to the World Health Organization, is the No. 1 nutrition disorder in the world -- affecting approximately 7.8 million women in the U.S. The most common symptoms of iron deficiency are fatigue, weakness, headaches and irritability.

Iron deficiency is more common among women (especially those of childbearing age), athletes, vegetarians and seniors. Before seeking treatment you should be properly diagnosed by your healthcare professional for an iron deficiency. However, once diagnosed, there are ways to help treat and reduce your deficiency.

Increasing iron intake can be as easy as making adjustments to your diet. There are several foods that contain a large amount of iron and can help restore the body's iron level. Some of these foods are:

* Red meat, fish and poultry

* Egg yolk

* Dark, leafy greens

* Beans, lentils, chick peas and soy beans

* Dried fruit

An iron-friendly diet should, in addition, consist of foods high in vitamin C, such as orange juice and tomatoes.

While maintaining a well-balanced diet can help supply the body with iron, sometimes it isn't enough. In cases such as these, an iron supplement is usually recommended. However, up to 47 percent of people who take iron supplements experience one or more side effects, such as nausea or constipation. In some cases, it is bad enough to make them stop their iron treatment altogether.

Often times, people are unaware that there are different forms of iron that may work better for their body's individual needs. Someone who tolerates iron supplements well might require a different form of iron than someone who often experiences side effects from their oral iron therapy. For those with a sensitive system, there are alternative supplements that provide the body with iron while minimizing common intestinal side effects such as nausea or constipation.

Since iron is an important building block for red blood cells, supplements combine two types of iron for maximum absorption. These forms of iron are most closely compared to those found in red meat and spinach, which are more naturally absorbed into the body to minimize stomach-related side effects.