Iron is one of the most important nutrients for good health and optimal function. Iron is responsible for helping your body produce hemoglobin, which is a protein in the red blood cells that carries vital oxygenated blood from the lungs to the rest of the body.
Iron is necessary for a healthy metabolism and to maintain overall health. Iron also helps us absorb nutrients, balance hormone levels, think clearly, and manage our moods. Iron is essential for physical growth, neurological development and cellular functioning.
When you don’t have enough iron, your body has a very hard time getting oxygen to the brain, tissues, muscles and your cells. This makes you feel extremely fatigued and weak. A severe deficiency in iron results in a health condition called anemia. Symptoms of anemia include: weakness, cold hands and feet, shortness of breath, dizziness, sore tongue, brittle or spoon-shaped nails, pica, poor appetite and more.
Iron deficiency is one of the most common nutritional deficiencies in the United States, according to the Centers for Disease Control (CDC), with about 10% of women considered iron deficient. Up to 80% of the world’s population are potentially short on iron, and 25% or more have iron deficiency-related anemia.
Iron comes from a variety of foods and is classified as either ‘heme’ or ‘non-heme’, depending on the source. Heme iron comes from meat, poultry, and seafood. Non-heme iron comes from plant food sources such as whole grains, nuts, seeds, legumes, and leafy greens. Heme iron is much more bioavailable and easier to absorb and utilize in the body.
While we have been well educated as to the importance of iron in the diet and avoiding iron deficiency anemia, the fact is–too much iron is very dangerous to your health and can be life threatening.
An iron overdose can be all of a sudden, or build up gradually, but either way can become an medical emergency.
Taking too much iron in the form of supplements has the potential of causing acute iron toxicity and can be deadly. In fact, one of the most dangerous items in your medicine chest may be your iron supplement pills. Young children and the elderly are especially vulnerable to overdoses of iron supplements.
Doses of supplemental iron (45 milligrams/day or more) can cause side effects including nausea, vomiting, cramps and constipation. Acute iron poisoning causes GI, cardiovascular, metabolic, hepatic and central nervous system toxicity, leading to liver failure and cardiovascular collapse as a cause of death.
Iron overload can happen in a couple different ways:
- Iron poisoning can occur when people overdose on iron supplements.
- Hereditary hemochromatosis is a classified as a genetic disorder characterized by excessive absorption of iron from food.
In either of the above scenarios, iron can accumulate, over time, in your body, leading to a serious health condition. Excess free iron in your body is a pro-oxidant (the opposite of antioxidant) and causes damage to your cells.
Excess iron accumulates in the heart, liver, joints, pancreas, and pituitary gland. If untreated, it can cause serious and irreversible organ damage, and can lead to heart attacks, diabetes, cirrhosis of the liver, arthritis, depression and even premature death.
Hemochromatosis is a genetic defect, caused by the body’s iron regulatory system not functioning properly, allowing iron to build up in the body. The body does not have a quick and easy way to dispose of extra iron, except through blood loss or donating blood. Women who are still menstruating can help rid their bodies of excess iron, but women who are postmenopausal cannot as easily.
The disorder tends to show up more frequently in older men and postmenopausal women. One study suggests that elderly people are more likely to have chronic positive iron balance and elevated total body iron than iron deficiency.
While hemochromatosis can be a genetic condition, many times people do not even realize they have it. They frequently get misdiagnosed as having arthritis, diabetes, heart disease, liver or gallbladder disease, or digestive disorders. Symptoms may not appear until advanced stages of the disease, and diagnosis can be tricky as routine blood tests may not reveal hemochromatosis.
People of Northern European descent, including people of Scottish, Irish and English descent are at increased risk, as is anyone with a family member with hemochromatosis.
Symptoms can include:
- Chronic fatigue-most common
- Joint pain or arthritis
- Loss of libido
- Abdominal pain
- Yellowish, reddish, or grayish skin color
Blood tests can help diagnose hemochromatosis by checking levels of iron and ferritin in the blood, along with total iron binding capacity and transferrin iron saturation. All adults over the age of 40 should be screened for this silent and possibly deadly condition.
Iron overload is treated by chelation therapy (drug therapy) or therapeutic phlebotomy, where a doctor will remove blood–or the patient can choose to routinely donate blood.
While iron from food is generally safe, iron supplementation can be harmful if your iron stores are sufficient. It’s best not to take iron supplements unless recommended by a medical professional. And by all means, keep iron supplements out of reach of children. They can be poisonous.
Iron and Cancer
Excess iron has been shown to lead to cancer in humans. Observational studies also suggest that a high intake of heme iron can increase the risk of colon cancer. Clinical trials in humans do show that heme iron from supplements or from red meat may increase the formation of cancer-causing N-nitroso compounds in the digestive tract, but more information is needed in this type of study.
Iron and Medication
Iron can also interact with medications including:
- Levodopa and Carbidopa—for Parkinson’s disease or restless leg syndrome
- Levothyroxine (Synthroid)—for hypothyroid conditions
- Proton pump inhibitors—for GERD
- Tetracycline, Ciprofloaxin, and Penicillin
While iron is an essential nutrient and many people in the world are iron deficient, you can get too much of a good thing. In short, iron is dangerous in higher quantities, especially if you are taking it as a supplement. If you happen to have a family member who has hemochromatosis, or if you are in a high risk group, be sure to ask your doctor to test you for hemochromatosis.
If you are a woman who is postmenopausal or an older man, it’s important to pay attention to you iron intake. Here are a few ways to ensure you can mitigate any negative effects of too much ingested iron.
- Eat foods containing lots of polyphenols, flavanols, phytonutrients, and other plant-derived antioxidant compounds. You can accomplish this by eating a wide variety of brightly colored fruits and vegetables.
- Drink coffee and/or tea with your meals. Coffee blocks iron absorption. Tea also blocks iron absorption–both black and green tea. This is possibly why coffee is constantly associated with lower rates of mortality.
- Eat dairy with meals, or after meals. Calcium is a potent inhibitor of iron absorption.
- Avoid eating red meat with iron-fortified food. The two types of iron tend to magnify each other, as heme iron actively increases absorption of non-heme iron.
- If you drink alcohol, make it red wine and lower-alcohol wines. Wine contains polyphenols that will inhibit iron absorption, while hard liquor like vodka, tequila, and gin enhance iron absorption.
- Drink mineral water. Mineral water contains magnesium and calcium that inhibit iron absorption and it reduces the cancer-causing effects of heme in the colon.
- Exercise reduces iron stores as it builds muscle.
- Living at altitude uses up iron stores more readily as the body has an increased need for oxygen in the blood.
While iron is an important nutrient, as we age, we tend to build up cumulative stores of iron in our bodies which can become a serious health threat, especially if we happen to have a genetic tendency to develop hemochromatosis, or are taking excess iron in the form of supplements. Be sure to have lab work to check for iron overload—or see a doctor or medical professional if you have any of the above symptoms of too much iron.