Iron is a double-edged sword. Insufficient iron results in anemia, a potentially serious condition that affects 25% of Americans with diabetes.
Too much iron is also problematic. When excesses of iron build up in the body—most often due to an inherited disorder called hemochromatosis—it damages organs and tissues and dramatically increases your risk of chronic diseases, including diabetes.
How Can Hemochromatosis Cause Diabetes?
Iron is absorbed in the intestinal tract from the food you eat. Once you have enough of this essential mineral, which is required for hemoglobin production and other essential functions, absorption is reduced, and iron levels stay at a constant optimal level.
For people with hemochromatosis, however, there’s a glitch in the body’s ability to regulate iron. The message to curb absorption doesn’t get through, and iron builds up. Because there is no storage depot for excess iron, it is deposited in tissues and organs throughout the body— unleashing a cascade of inflammation and free radical damage that causes serious organ damage.
One of the biggest problems is that the pancreas is a prime storage spot for excess iron. Too much iron in the pancreas impairs the ability of beta cells to synthesize and secrete insulin. To add insult to injury, iron overload also affects the liver, which plays a role in insulin sensitivity, and cells throughout the body become insulin resistant as well.
The end result is increasing blood sugar levels and, all too often, an eventual diagnosis of diabetes. Approximately 50% of people with hemochromatosis develop diabetes (type 1 or type 2).
Unfortunately, Iron Overload Can Go Undetected
Early signs of hemochromatosis include fatigue, muscle weakness, and joint pain—vague complaints that could be attributed to any number of conditions. Furthermore, symptoms rarely become evident before age 40 for men and age 60 for women. (Menstrual periods and childbirth make women less likely to store excess iron.) At that point, symptoms are often dismissed as a normal part of aging.
That’s why hemochromatosis has been called a “stealth disease.” By the time it is diagnosed, iron excesses have been accumulating for decades and real problems have already begun.
Should You Be Tested for Hemochromatosis?
Hemochromatosis is the most common inherited disorder in North America and Europe. About 10–15% of people of northern European ancestry are carriers of a single copy of the predisposing mutation (C282Y variant of the HFE gene). Although the disorder doesn’t develop unless both parents pass on the mutated gene, more than a million Americans have two copies of the gene, or full-blown hemochromatosis.
I am not suggesting that everyone rush out and get tested for hemochromatosis risk, but if you have any family history of this condition—or of unexplained diabetes, liver or heart disease, joint pain, etc.—discuss this with your doctor.
I also recommend testing ferritin, a protein that stores iron. Iron overload is missed on routine blood tests, such as CBC/complete blood count. A high ferritin level is another indication for ruling out hemochromatosis with genetic testing.
The Dangers of Untreated Iron Overload
Hemochromatosis and iron overload can affect many other aspects of your health in addition to raising your risk of diabetes:
- Liver: Around 70% of patients with hemochromatosis have serious liver disease, including cirrhosis and liver cancer.
- Joints: Iron deposits in the joints are associated with pain, stiffness, and bony growths that persist and sometimes progress even after treatment.
- Heart: Cardiovascular abnormalities such as arrhythmias, dilated cardiomyopathy—and in severe cases heart failure—are common in individuals with iron overload.
- Hormones: Related hormonal problems such as hypothyroidism (low thyroid function) and hypogonadism (low sex hormones) can result in fatigue, erectile dysfunction, infertility, and menstrual irregularities.
- Skin: When iron stores are extremely high, it collects in the skin, which takes on a bronze or gray hue. Because advanced hemochromatosis is often accompanied by diabetes, the condition has been referred to as “bronze diabetes.”
Even in the absence of hemochromatosis, elevated iron levels are associated with a significantly increased risk of type 2 diabetes, heart disease, and other chronic conditions.
There is no cure for hemochromatosis—but unlike many genetic diseases, it can be successfully treated.
The most effective treatment is phlebotomy, which involves removing blood (and excess iron) from the body. It’s a simple process, like donating blood at a blood bank or hospital—and in some cases, the blood is used for transfusions.
Phlebotomy may initially be required once or twice a week, depending on the level of iron. After levels normalize, treatments generally taper down to an average of once every two to four months.
Chelation is sometimes used, although it is generally reserved for patients who cannot undergo phlebotomy. Chelating agents, administered orally, by injection or intravenously, bind to excess iron, which is then excreted in the urine or stool.
By reducing iron overload, these treatments help to improve symptoms—plus they can help to slow, and in some cases reverse, progression. Better yet, if hemochromatosis is diagnosed and treated early and regularly, organ damage can be prevented altogether.
What Is the Best Diet for Hemochromatosis?
In addition to reducing your iron levels, it’s also important to minimize your intake of iron.
- Cut back on red meat: Red meat contains heme iron, the most easily absorbed form–so it’s important to limit your intake.
- Eat more plant foods: Produce provides a bounty of protective antioxidants and other phytonutrients. Although some vegetables such as leafy greens contain iron, it is nonheme, which is not very well absorbed. Fiber-rich foods and phytic acid/phytate (in beans and grains) inhibit iron absorption.
- Drink coffee & tea with meals: Tannins in these beverages interfere with iron absorption.
- Reduce or eliminate alcohol: Hemochromatosis is hard on the liver and alcohol can make it worse. Cut out alcohol if you have any signs of liver problems.
- Avoid iron-fortified foods: Read packages and avoid cereals and other processed foods enriched with iron.
I also recommend taking a good daily multivitamin supplement. Antioxidants are important to counter the torrent of oxidation triggered by excess iron. Vitamin C, however, enhances iron absorption, so limit your supplemental dose to 500 mg and take it between meals.
You obviously want to avoid supplemental iron. Iron is included in many multivitamins, so read labels carefully. In fact, unless blood tests reveal a low iron level, I recommend that everyone avoid supplements containing iron.
You may also want to consider giving blood. Some studies suggest that healthy people who give blood a couple of times a year have a reduced risk of heart attack, likely because of its effect on iron stores.