Clay

Contents of this page:
Synonyms Evidence Dosing Safety	Interactions

Clay

Synonyms

Akipula, aluminium silicate, anhydrous aluminum silicates, askipula, beidellitic montmorillonite, benditos, bioelectrical minerals, chalk, cipula, clay dirt, clay dust, clay lozenges, clay suspension products, clay tablets, colloidal minerals, colloidal trace minerals, fossil farina, humic shale, Indian healing clay, kaolin, kipula, mountain meal, NovaSil, panito del senor, plant-derived liquid minerals, Terra sigillata , tirra santa, white clay, white mud.

Evidence

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Uses based on scientific evidence	Grade^*
Fecal incontinence associated with psychiatric disorders (encopresis): clay modeling therapy in children There is not enough scientific research to support a recommendation for play with modeling clay as an effective therapeutic intervention in children with constipation and encopresis.	C
Functional gastrointestinal disorders There is not enough scientific evidence to recommend the medicinal use of clay by mouth in patients with gastrointestinal disorders. Some clay preparations have been found to be similar to Kaolin® and Kaopectate®, which are used to treat gastrointestinal disturbances including diarrhea. However, overall, there are significant potential risks that accompany the use of clay, including intestinal blockage and injury as well as lead poisoning.	C
Mercuric chloride poisoning Clay lozenges have been used historically in the treatment of mercuric chloride poisoning, and were officially mentioned in several European pharmacopoeias, including the Royal College, until the middle 19thCentury. However, there is not enough scientific evidence to recommend the use of clay by mouth for poisoning at this time, as there is risk of clay itself containing contaminants.	C
Protection from aflatoxins Aflatoxins are toxic substances from the fungus Aspergillis flavus . This fungus infects peanuts, and ingestion of aflatoxins from peanuts and cereals (primarily in warm and humid regions) has been associated with liver cancers in humans and multiple cancers in animals. Phyllosilicate clay has been shown to adhere to aflatoxins in laboratory study, and HSACS clay in animal diets may diminish or block exposure to aflatoxins. However, the risks of chronic clay exposure likely do not justify the potential benefit.	C

*Key to grades
A: Strong scientific evidence for this use;
B: Good scientific evidence for this use;
C: Unclear scientific evidence for this use;
D: Fair scientific evidence against this use;
F: Strong scientific evidence against this use.

Grading rationale

Uses based on tradition or theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Acidosis, animal bites, cancer, constipation, detoxification, diarrhea, dysentery, eye disorders, fevers, heart disorders, hemopurification, menstruation difficulties, nutrition, plague, poisoning, skin fairness, smoking, stomach disorders, syphilis, vomiting, vomiting/nausea during pregnancy, water purification, weight loss.

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Adults (18 years and older)

There is not enough scientific evidence to recommend safe use of clay.

Children (younger than 18 years)

There is not enough scientific evidence to recommend safe use of clay in children.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

There are no reports of allergy to clay in the available scientific literature. However, in theory, allergy/hypersensitivity to clay, clay products, or constituents of clay may occur.

Side Effects and Warnings

The practice of eating dirt, clay, or other non-nutritious substances is called "pica" or "geophagia," and may occur in early childhood or in mentally handicapped people. Clay or dirt eating has been associated with lead poisoning in infants, children, and pregnant women, with potential risks such as low red blood cell count and brain damage. Death has occurred, related to complications of lead poisoning and brain damage after drinking from a glazed clay pitcher. Clay pots containing candy have been recalled in the United States by the Food and Drug Administration due to high levels of lead in the candy, absorbed from clay pots. Pica may carry a risk of central nervous system damage. The risk of neurolathyrism, a neurodegenerative, irreversible disorder that causes spastic paraparesis of the body leading to paralysis, was reported to quadruple in a case-control study in Ethiopia when cooking grass pea with clay utensils.

Clay products may contain varying amounts of contaminants including aluminum, arsenic, barium, nickel, and titanium. Elevated levels of 2,3,7,8-tetracholorodibenzo-p-dioxin have been found in fish and eggs from chickens fed a diet including clay. Chronic clay eating has also been associated with imbalances of blood chemistry, such as increased calcium or magnesium, decreased iron and potassium. Myopathy due to severe hypokalemia (low blood potassium levels) has been reported in one case report with large quantities of clay ingestion.

In the 19th Century, a condition was described called "Cachexia Africana," including a swollen appearance, enlarged heart, increased urination, and death. Descriptions of people who chronically ate clay in the 19th Century noted skin that was initially dry and shiny, and in late stages of disease, especially in children, skin ulcerations occurred over the arms and legs. Chronic clay eating has also been associated with small gonads (testes), and muscle injury.

Heartburn, gas, loss of appetite, constipation, diarrhea and vomiting after meals have been reported with use of clay. One study on safety using NovaSil clay for two weeks found that mild gastrointestinal effects occurred such as abdominal pain, bloating, constipation, diarrhea and flatulence, but that these effects were no more common than placebo. Clay eating has also been associated with intestinal blockage and injury, bowel rupture (perforation), formation of stones in the intestine, and enlarged liver/spleen.

It is reported that children with pica are more likely to develop lung infections. Chronic bronchitis, trouble breathing, and infections have been associated with dust exposure in the heavy clay industry. Hookworm infections may result from eating clay. Tetanus contracted from clay has been described in an infant who ate clay, and in a newborn whose umbilical cord was wrapped in clay.

One study on safety using NovaSil clay for two weeks found that mild gastrointestinal effects occurred such as abdominal pain, bloating, constipation, diarrhea and flatulence, but that these effects were no more common than placebo.

Pregnancy and Breastfeeding

Use of clay during pregnancy or breastfeeding is not recommended. Eating clay during pregnancy may increase the risk of toxemia or complications at birth.

Interactions

Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.

Interactions with Drugs

When taken together, clay may inhibit the absorption of drugs such as cimetidine (Tagamet®).

Kaolin has been shown to reduce the bioavailability of quinine in laboratory study.

Interactions with Herbs and Dietary Supplements

Clay can interfere with iron absorption.