When a woman, pregnant or NOT desires or craves chalk, for taste or the sensation of crunching, there is an iron  deficiency in the woman and she is  anemic. (more tired, need energy building foods). Once she gets the iron balanced in her system, she will NO LONGER have the craving for the chalk.
When one supplement’s their diet with iron pills, it is important to take the iron pills with something acidic, like orange juice, BECAUSE it helps to ENHANCE the absorption of iron in your body.
When one takes rolaids, it is COUNTER PRODUCTIVE to the absorption of the iron in the body. Rolaids
is an ANTACID, (not acidic) and you NEED acid to absorb the iron in your body. So, you are just canceling out the iron supplement each time a rolaid is taken.  It doesn’t matter if one takes one or ten…IT IS NOT GOOD!  Research shows if a pregnant woman has to choose between chalk and rolaids, the more favorable choice is the chalk.  It doesn’t have the antacid element to it.  STOP rolaids immediately if your doctor has suggested this as a solution away from the chalk.
Eating iron rich foods is imperative.  If one needs to find foods that will satisfy a need to CRUNCH try something like ALMONDS or other kinds of seeds or nuts rich in iron. Leafy green veggies are high in iron and so are dried apricots which are ALSO high in Vitamin C, ( an acidic source )
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Floradix is a liquid formula that will help to enhance the iron absorbtion in one’s body when eating iron rich foods.
Floradix Formula Iron (250mL) Brand: Flora http://www.amazon.com/Floradix-Formula-Iron-250mLBrand/dp/B0002DUFKU/ref=sr_1_3?ie=UTF8&s=hpc&qid=1254578184&sr=8-3 Uses: Energy, Anemia etc.. The absorption rate of Floradix (liquid iron gluconate) is twenty-five per cent compared solid iron tablets that have an absorption rate of two to ten per cent. Floradix provides maximum absorption by using the most highly absorbable form of iron, iron gluconate. Floradix also contains B vitamins and vitamin C to enhance absorption, herbal extracts to increase digestion, and fruit juices to ensure proper stomach acidity. A twenty milligram dose of Floradix satisfies the Recommended Daily Allowance (RDA) of fifteen milligrams of iron for women of child-bearing age.
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Homeopathic remedies to help get your minerals balanced in one’s body are:
1. Â Ferrous Phosphate: Â 6X or 12X strength, take 1-4 times per day, 4 pellets. This very useful cell salt is known as the “oxygen carrier”. It has the ability to carry oxygen to all the cells of the body for use in conversion to energy.
2,  Bio-chemic Tissue Salts:  take 5/6 of these COMBINATION  3-4X’s per day. The 
12 Tissue/Cell Salt Combination As the name implies, this is a combination of all 12 salts in a single tablet. This combination can be used daily in much the same way as you would take a vitamin or supplement. To treat specific conditions, however, select one of the single salts listed above. RECOMMENDED POTENCY – 6X is the most widely used potency These are all the different MINERALS combined into the 12 Tissue/Cell Salts. Calcarea Fluoricum Calcarea Phosphoricum Calcarea Sulphuricum Ferrum Phosphoricum Kali Muriaticum Kali Phosphoricum Kali Sulphuricum Magnesia Phosphoricum Natrum Muriaticum Natrum Phosphoricum Natrum Sulphuricum Silicea (Silica)
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How Much Iron?
The recommendation increases to 27 mg for pregnant women.
http://www.healthcastle.com/iron.shtml
Iron Rich Foods containing Heme Iron (Iron found in animal protein)
Excellent Sources               Good Sources
Clams                                       Beef
Pork Liver                                Shrimp
Oysters                                     Sardines
Chicken Liver                           Turkey
Mussels
Beef Liver
Iron Rich Foods containing Non-Heme Iron
Excellent Sources Good Source
Enriched breakfast cereals Canned beans
Cooked beans and lentils         Baked potato with skin
Pumpkin seeds                               Enriched pasta
Blackstrap Molasses                         Canned asparagus
Warning: Pregnant women should not eat liver because of its very high Vitamin A content. Large amounts of Vitamin A can be harmful to the baby.
The absorption of Non-heme iron can be improved when a source of heme iron is consumed in the same meal. In addition, the iron absorption-enhancing foods can also increase the absorption of non-heme iron. While some food items can enhance iron absorption, some can inhibit or interfere iron absorption. Avoid eating them with the iron-rich foods to maximize iron absorption.
Iron Absorption Enhancers  (GOOD to eat)
Meat/fish/poultry
Fruits: Orange, Orange Juice, cantaloupe, strawberries, grapefruit etc
Vegetables: Broccoli, brussels sprouts, tomato, tomato juice, potato, green & red peppers
White wine
Iron Absorption Inhibitors  (BAD to eat)
Red Wine, Coffee & Tea
Vegetables: Spinach, chard, beet greens, rhubarb and sweet potato
Whole grains and bran
Soy products
Is Spinach a good source of Iron? Written by Gloria Tsang, RD
Published in May 2006 (HealthCastle.com)
Spinach and Iron has been a highly discussed topic in our free nutrition forum. Many readers know that spinach is a source of iron. However they are confused that spinach is said to contain an iron absorption inhibitor as mentioned in our Iron Rich Foods article.
Spinach – a source of Iron
Spinach is a source of non-heme iron, which is usually found in vegetable sources. Unlike heme iron found in animal products, non-heme iron is not as bioavailable to the body.
According to the USDA National Nutrient Database, one cup of cooked spinach provides ~3.5mg of iron whereas a cup of raw spinach only contains 1 mg of iron.
Spinach – also inhibits(stops) iron absorption
Spinach also contains oxalic acid (sometimes referred as oxalate). Oxalic acid binds with iron, hence inhibiting its absorption.
Spinach is not the only food containing high levels of oxalic acid. Whole grains such as buckwheat and amaranth, other vegetables such as chard and rhubarb, as well as beans and nuts all contain significant levels of oxalic acid.
So Should you or Should you not eat Spinach?
You do not need to give it up if you are a spinach lover! Simply eat spinach with any foods containing iron absorption enhancers. Here are some examples:
Iron Absorption Enhancers  (Good to eat)
Meat, fish, or poultry
Fruits: Orange, Orange Juice, cantaloupe, strawberries, grapefruit and other Vitamin-C rich fruits
Vegetables: Broccoli, brussels sprouts, tomato, tomato juice, potato, green & red peppers
White wine