By Dr. Mercola
Chewing on ice on a hot summer day may relieve some heat, but if you crave ice frequently, it may mean something more. Chewing ice is a form of pica, or the craving to eat something non-nutritional.
Pica is seen more frequently in children, but ice chewing is an addiction that crosses all age boundaries. Craving a non-nutritional substance is often related to a nutritional deficiency.
In this case, chewing ice may be a symptom of iron deficiency or anemia.1 To fit the criteria for pagophagia, or the addiction to chewing ice, you must persist in chewing ice for one month or more. People who are addicted to chewing ice will seek out ice, even to the point of eating freezer frost to meet their needs.2
Although a simple craving for ice may mean you are iron deficient, there is a complex interaction between nutritional requirements and behavior. In many instances simply supplementing with iron may fix the problem.
However, since iron levels can create significant problems when they are too high or too low, it's important to understand the process and monitor your iron levels.
Pagophagia With Iron Deficiency
To demonstrate the association between chewing ice and iron deficiency, one study evaluated the behavior of 81 patients who suffered iron deficiency anemia and found pagophagia was a common form of pica.3
In this population the 16 percent of participants who experienced pagophagia exhibited relief from their symptoms more quickly with iron supplementation than the recovery of their hemoglobin levels may have indicated.
While symptoms of pica have been present for centuries, there appears to be a young community of physicians who may not be aware of the links between craving non-nutritional substances and a nutritional deficiency.4
In one case study, both the patients and the physicians treating them were unaware of the significance of pica behavior and the links to iron deficiency.
The researchers recommend that physicians look closely for chronic blood loss in patients who exhibit pica behaviors as it may be an indication of slow blood loss and iron deficiency. The anemia is caused when your level of red blood cells is lower than normal and reduces the amount of oxygen your body can deliver to your cells.
Without oxygen your body is unable to function effectively. However, when the loss occurs slowly your body may adapt and you may not notice a difference in performance or function until your level of red blood cells becomes dangerously low. In other words, you may become functionally anemic.
Risks Associated With Chewing Ice
In this short video you'll discover some of the ways that ice can damage your teeth and jaws. An addiction to chewing ice may seem innocuous but there are dangers to the condition.
The side effects are not nearly as dangerous as an addiction to chemicals, such as tobacco, drugs or alcohol, however it may cause dental damage and lack of treatment of the anemia can cause heart damage.
Some patients have gone as far as purchasing snow cone makers for home and work to meet the needs of their addiction.5 However, when not chewing on crushed ice or ice from a snow cone maker, you may be tempted to bite down on a common ice cube, increasing the potential for damage to your teeth.
In the throes of addiction you may crave ice like a smoker needs a cigarette to soothe his craving. Chewing through ice may chip your teeth, damage your gums, damage your tooth enamel or damage existing fillings or crowns.6 You may also suffer from sore jaw muscles or aggravate a temporomandibular joint disorder.
What's the Link Between Ice and Anemia?
There are several theories as to why you may crave chewing ice when you have an iron deficiency. Some of the gastrointestinal symptoms of an iron deficiency are a sore tongue, dry mouth,7 altered sense of taste, difficulty swallowing and mouth sores.8
Each of these symptoms may be alleviated by chewing or sucking on cold ice that may help reduce swelling and reduce discomfort. However, further research has also found that chewing on ice when you are iron deficient changes neurological processing that improves cognitive functioning.9
Does Chewing Ice Improve Cognitive Function?
Other symptoms of iron deficiency and anemia are fatigue and exhaustion that often affect cognitive skills and ability.10 Researchers hypothesized that chewing ice may trigger changes in the brain's vascular system that could lead to an increased amount of oxygen delivery.
This increased perfusion of blood and oxygen may then result in an increase in alertness and processing speed.11
In this study researchers were able to demonstrate that chewing ice in individuals who suffered from iron deficiency indeed improved their processing speed, while it had no effect on their healthy control participants.
They compared testing results between people who were iron deficient and had water versus those who chewed on ice directly before testing.12 The researchers theorize the reflexive increase in blood flow to the brain may be related to a dive reflex.
Study author Melissa Hunt, Ph.D., clinical psychologist at the University of Pennsylvania, describes the reflex:13
"If you think about whales and dolphins diving, the water gets colder and their peripheral blood vessels constrict and shunt all the blood to the internal organs and the brain. It is sort of vestigial, but humans do show the dive reflex."
This reflex appears to be triggered when cold water touches the face, shunting more blood flow to the brain, thereby providing a boost in cognitive functioning. Hunt had not heard the participants or her patients describe needing ice for a jolt of energy, but rather as a craving. Dr. Michael Bromberg, hematologist at Temple University, said:14
"Patients tend to be somewhat secretive about these kinds of behaviors. You have to tease it out. I had one patient tell me: 'I love ice. It's better than sex.'"
How Iron Deficiency Anemia Affects Your Health
There are several ways you may experience iron deficiency, with or without anemia. It may originate from a chronic blood loss, such as from gastrointestinal polyps, chronic heavy menstrual periods, chronic bleeding stomach ulcers15 or following certain surgical procedures that reduce the amount of iron your body may absorb, such as a gastric bypass procedure.16
The condition may result in long-term damage from both the original problem causing the anemia and from the anemia itself. The first step is to discover the reason behind the blood loss. The loss of oxygen supply to your cells may be experienced as chronic fatigue, shortness of breath, dizziness and fast or irregular heartbeat.
Complications from long-term iron deficiency and chronic anemia can include heart failure from long periods of time when your heart must beat faster to deliver more blood to your cells to meet the oxygen need.17
Children are also at risk from iron deficiency anemia. While pregnant, you may deliver your child too soon or with a low birth weight, both associated with negative outcomes for the child. Children who are chronically anemic may experience delayed growth and development and an increased vulnerability to infections.18
Ask for These Blood Tests
Before taking matters into your own hands, it's important you know if you are iron deficient. Having too much iron in your body can be even more damaging to your health than having too little. Like most nutrients there is a happy medium at which your body functions optimally.
There are three basic reasons for suffering from anemia: blood loss, impaired blood cell production or destruction of blood cells.19 In each case it is important to not only diagnose the anemia, but also to find the reason you are experiencing blood loss as, in some cases, supplementing with iron can cause serious damage.
Checking for iron deficiency, and overload, can be done with a simple blood test called a serum ferritin test. It measures the molecule in your blood that carries iron. If your ferritin levels are low, then your iron levels are also low. A healthy range for serum ferritin is between 20 and 80 nanograms per milliliter (ng/ml). Some labs extend the highest acceptable level to 300 ng/ml,20 but I believe that is much too high.
The dangers of iron overload are serious and potentially life threatening. You can read more in my previous article, "Iron in Your Blood."
Other testing that may be important in the diagnosis of your iron deficiency include a complete blood count during which a technician will determine the size, number and volume of your blood cells. In combination with a serum ferritin level, your physician may also order other testing if an immune attack on your red blood cells or defects in enzymes, hemoglobin or clotting are suspected.
Boost Your Iron Stores Naturally
Depending upon your iron levels, you may be able to alleviate your iron deficiency by improving your eating habits. There are two different types of iron you find in foods: heme and non-heme iron. Heme iron is found in meat and seafood.21
Plant-based foods such as fruits, vegetables and nuts contain non-heme iron. Although these sources may not be absorbed as quickly as heme iron, they are a very important part of a nutritious diet. Whether you're eating heme or non-heme nutritional sources of iron, you may want to also include foods that are high in vitamin C to improve absorption.
Tomatoes, yellow and red peppers, citrus fruits, kale, broccoli and Brussels sprouts top the list of foods high in vitamin C. Foods that are high in iron include:22
✓ String Beans
✓ Beet Greens
✓ Dried Peas
✓ Dried Beans
✓ Tomato Products
If you need more than foods high in iron to raise your iron levels to normal levels, after you know why your levels are low, consider a supplement using ferrous bisglycinate instead of ferrous sulfate. The most commonly prescribed supplement is 325 milligrams (mg) of ferrous sulfate taken three times a day.23 However, the side effects increase the likelihood patients stop taking the medication.
In comparisons between different oral preparations of prescription iron supplements, researchers found wide variations in the time in which the supplements dissolved and the bioavailability of the supplement.24 Important factors included the type of preparation and the form of the iron in the supplement.
In recent research the bioavailability of iron-rich mineral water appeared equivalent to synthetic iron formulations.25 Supplementation with ferrous bisglycinate has the added benefit of little to no gastrointestinal side effects, lower dosages needed to correct iron levels, and often a lower cost.26,27,28
How Vitamin D May Affect Your Iron Status
Vitamin D may have an effect on the production of red blood cells, called erythropoiesis. In one study evaluating blood sampling from over 550 participants, the researchers were able to demonstrate an association between vitamin D deficiency and an increased risk of anemia.29
This should not be surprising as vitamin D plays an integral role in many of your body's functions, including gastrointestinal health, depression, brain health, metabolic functioning and cancers. Normalizing your vitamin D levels is a simple, effective and inexpensive way of optimizing your overall health.
An estimated 50 percent of the general population is at risk of vitamin D deficiency and insufficiency. Sunlight is the ideal way to optimize your vitamin D levels, but the only way to know if you have therapeutic levels is to have it measured. There is a significant difference between your level of vitamin D to prevent disease and to promote your health.
In my previous article, "Do You Need a Vitamin D Supplement to Maintain Ideal Levels?" I discuss when you may consider a supplement, what's important to do in conjunction to taking that supplement and how to increase your absorption of vitamin D from the sun.