Bentonite

Bentonite is formed from volcanic ash and has an extraordinary capacity to absorb water and electrolytes. It is used to detoxify, cleanse skin and hair and aid digestion. Bentonite may also help fight infections, lose weight and relieve allergies.

What is bentonite

Bentonite has been used since ancient times to promote health (1). Bentonite is a type of clay that is formed when volcanic ash reacts with seawater and absorbs its minerals. The resulting clay is tasteless and odorless and its color can range from a light yellow or green to a dark brown or black color. Bentonite has a soft consistency and does not stain (2, 3).

Bentonite is named after the largest spring in the world (Fort Benton, Wyoming). The name of its main constituent, montmorillonite, was derived from the place where it was first discovered (Montmorillon, France). The USA is the largest producer of bentonite, ahead of China, Greece and India (4). Humans have been using clay such as bentonite both externally and internally for thousands of years. Science believes that "geophagy" or "eating the earth" is an adaptive behavior that allowed us to absorb nutrients from the earth and eliminate parasites and toxins from the digestive tract (1, 5, 6).

Bentonite and other types of clay were traditionally consumed or applied to the skin for the following reasons (1, 7):

Balancing nutrient deficiencies
Treatment of poisoning
Treatment of infections
Relieving diarrhea and other digestive problems
Relieving skin irritations
Cleansing the hair and improving the appearance of the hair

Components and mechanisms of action of bentonite

The main component is montmorillonite, a soft clay formed from layers of silica and aluminum. Montmorillonite is normally bound to many clay minerals, especially sodium, calcium, magnesium and aluminum (8, 3). Bentonite may also contain small impurities such as other clays (illite, kaolinite) and crystalline silica (quartz, cristobalite). Although the quantities typically found in bentonite are not dangerous, both kaolin and crystalline silica dust can cause lung disease if inhaled in large quantities. Silica dust has also been linked to autoimmune diseases, kidney damage and cancer (3, 8). The negative charge of montmorillonite is partly responsible for the effects of bentonite. Similar to a magnet, montmorillonite attracts positively charged molecules and binds them to its surface. In this way, montmorillonite can bind many heavy metals and toxins, preventing them from being absorbed by the body (9, 10). Montmorillonite particles have a surprisingly large surface area, which gives them a high capacity to bind toxins. In addition to toxins, these particles also absorb water, which causes the clay to swell (10).

Different types of bentonite

There are two primary types of bentonite: sodium bentonite and calcium bentonite (3):

Sodium bentonite can absorb more water. Although this makes it more effective when it comes to eliminating toxins, the clay is very alkaline and can be too aggressive for the skin. Taken orally, it can cause constipation.
Calcium bentonite absorbs more electrolytes, which makes it more effective in cases of poisoning. This clay is less alkaline and absorbs less water than sodium bentonite.

Although it is generally believed that only calcium bentonite can be used internally, both types are safe and harmless.

Potential health benefits of bentonite

Bentonite binds toxins and can promote detoxification of the body

By binding various substances in the digestive tract, ranging from fungal toxins to pesticides and heavy metals, bentonite may help prevent the absorption of these toxins into the bloodstream and promote their elimination. Here is an overview of the toxins that bentonite could help detoxify:

Mold toxins and other toxins

Aflatoxins are toxins produced by molds. Aflatoxins are toxic and can have negative health effects. They have even been linked to the development of liver cancer (11). Bentonite binds alfatoxins and thus prevents poisoning. In 3 clinical studies with a total of almost 300 subjects exposed to alfatoxin, bentonite (1.5 to 3 grams per day) was able to reduce alfatoxin levels in blood and urine (12, 13, 14). Fumonisin is another toxic mold toxin whose levels in urine were reduced in another human study with 200 test subjects by daily administration of 1.5 to 3 grams of bentonite (15). Bentonite also reduced the levels and toxic effects of a number of other fungal toxins (aflatoxin, fumonisin, deoxynivalenol and ochratoxins) in breeding cattle and reduced damage to the liver, kidneys and digestive tract (16, 17, 18, 19, 20, 21, 22).

In summary, bentonite may be effective in treating or protecting against poisoning from molds and other fungal toxins.

Pesticides

Paraquat is an extremely toxic but widely used weedkiller. Even small amounts of the concentrated solution can be fatal. Two analyses found traces of paraquat (up to 25mg per gram) in an estimated 10% of all marijuana plants. Since a small percentage passes into the smoke, marijuana users may be exposed to this chemical (26, 27, 28, 29). Bentonite can bind paraquat and is routinely used in intensive care units for intoxication (30, 31, 32, 33). Organophosphates are another type of toxic pesticide that are absorbed through the skin and accumulate in the body. Bentonite has been shown in one study to reduce organophosphate absorption through human skin tissue (34). Bentonite can also absorb organochloride pesticides. These chemicals are highly persistent and potentially toxic to humans when consumed via contaminated food (35, 36). By binding pesticides from water, food and beverages, it can protect the health of the consumer. Whether bentonite can also be used for acute poisoning with some of these pesticides (in addition to paraquat) remains to be tested in clinical trials (37, 38, 39, 40, 41).

Heavy metals

Lead is a heavy metal that is toxic to several enzymes and organs (especially the brain). Lead can enter the body through contact with lead-containing products, dust, contaminated water and contaminated food. Bentonite has been shown to prevent lead accumulation in pigs and lambs (42, 43, 44). Cadmium can contaminate soil and groundwater near industrial areas. It has been linked to cancer, infertility and organ damage in humans. In fish that ingested cadmium with their feed, bentonite was able to reduce the toxic effects of cadmium (45, 46). In summary, bentonite can bind heavy metals and possibly prevent them from entering the bloodstream. However, further research is needed as all studies to date have been conducted with animals. Bentonite can be used to promote skin health. The following benefits of bentonite have been observed when used topically:

Allergies and skin irritation

In 2 clinical studies with over 200 participants suffering from allergies to poison ivy and oak leaves, lotions containing bentonite reduced eczema (47, 48). In another study of 33 subjects suffering from occupational eczema on the hands, a cream containing bentonite reduced eczema and the use of corticosteroids in 76% of cases (49).

In two studies of babies with diaper rash, a cream containing bentonite improved and accelerated wound healing more effectively than a herbal preparation (calendula) (50, 51). In summary, bentonite could be helpful for skin allergies and skin irritations.

Acne

Bentonite applied to the skin may help people suffering from acne by killing infectious bacteria and absorbing the oil that clogs pores. A commercially available face mask with a similar clay reduced the number of acne lesions in a clinical trial involving nearly 200 participants (4, 52, 53, 54).

Although the limited evidence is promising, further research is needed into the effect of bentonite on acne.

Skin ageing

An anti-aging cream containing bentonite improved skin hydration and protected human skin tissue from UV rays (55). However, this was a cell study, which means that further studies are needed.

Wound healing

Synthetic materials combining bentonite with antimicrobial agents are being investigated as wound dressings. They have been observed to improve wound closure and kill infectious bacteria without damaging skin cells (56, 57, 58). Combinations of bentonite with similar clays (zeolite and hallosite) accelerated blood clotting in human blood samples and in injured dogs and rats (59, 60, 61, 62). These benefits have only been studied in cells and artificial tissues, so further research is needed to determine whether bentonite is effective in promoting wound healing in humans.

Bentonite could support digestive health and balance gut flora

A healthy gut wall helps digest food, absorb nutrients and fight infection. A damaged intestinal barrier, impaired enzyme activity or an imbalance in gut flora can lead to digestive problems (63). In a clinical study of 500 patients with irritable bowel syndrome, bentonite (3 grams, three times a day) relieved symptoms of constipation in patients - possibly by binding to the intestinal wall and reducing pain. In pigs and mice with irritable bowel syndrome, bentonite reduced inflammation by absorbing cytokines and blocking their production (64, 65, 66).

Interestingly, bentonite has been used for centuries to relieve diarrhea - possibly to absorb microorganisms, toxins and water in the gut. In an old study of 35 subjects, bentonite (2 tablespoons, three times a day) quickly relieved diarrhea, stomach pain, nausea and lack of appetite (67). In animals, bentonite added to the diet increased the activity of digestive enzymes, maintained a normal intestinal barrier, and promoted nutrient absorption and utilization (63, 68, 69, 70, 71, 72).

Bentonite may also help with intestinal flora imbalances. In studies conducted with animals, bentonite had the following effects:

An increase in the amount of "good" intestinal bacteria that aid digestion and a reduction in "bad" bacteria (63, 66, 69, 73).
Restore balance to imbalances caused by high-fat diets by reducing the levels of obesity-promoting bacteria (74, 75). In summary, bentonite may be effective in relieving constipation caused by irritable bowel syndrome and may also help with diarrhea. Bentonite not only has the potential to improve the function of the digestive system, but also to restore the balance of the intestinal flora. However, the latter has so far only been observed in animals.

Bentonite could promote weight loss

Bentonite could promote weight loss by optimizing the intestinal flora (74, 75). In rats fed a high-fat diet, bentonite increased fat excretion and reduced the growth of bacteria that promote obesity and inflammation. Furthermore, bentonite reduced weight gain, blood lipid levels and fat accumulation in the liver (74, 76, 77). In addition, a reduction in weight and body fat levels was observed in an observational study of 49 people who followed a weight loss program that combined a low-calorie diet with a cleansing supplement containing bentonite. However, the exact contribution of bentonite to weight loss in this study is unclear (78). In summary, there is limited evidence to suggest that bentonite may help with weight loss.

Bentonite could help relieve allergies

In a clinical study of 20 people allergic to dust mites, a single dose (0.28 ml per nostril) of a spray containing bentonite relieved nasal congestion and inflammation of the nasal mucosa within 60 to 90 minutes (79).

Bentonite could help with hyperthyroidism

Bentonite can bind the thyroid hormones T3 and T4. This reduced the blood levels of these two thyroid hormones and symptoms of an overactive thyroid gland in rats and mice (80). Whether this effect also occurs in humans has yet to be investigated in further clinical studies. Bentonite could help prevent the accumulation of waste products in the body Creatinine, urea and uric acid are three metabolic waste products that can accumulate in the blood of people with kidney damage, as these waste products are mainly excreted in the urine. In rats, bentonite was able to bind these substances and prevent them from reaching the bloodstream (81, 82, 83).

Bentonite could fight infections

In cell-based and animal studies, bentonite has been shown to kill a wide range of bacteria, including bacteria that can cause the following conditions and problems:

Diarrhea and food poisoning (84, 85, 86, 87, 88, 89)
Skin infections (84, 85, 89)
Stomach ulcers (90)
Antibiotic-resistant infections (84)
Infections of other tissues caused by intestinal bacteria (91)
Plague (85)

Bentonite absorbed viruses - including the viruses that cause influenza, dengue fever and conjunctivitis - and in some cases reduced their capacity to cause disease. This raises the possibility of using bentonite to combat viral infections in humans (92, 93, 94, 95).

Bentonite could have anti-cancer activity

In cell-based studies, bentonite has been shown to have an effect on the following types of cancer by reducing cell growth and cancer cell survival:

Liver cancer (96, 97)
Brain tumors (98)
Leukemia (99)
Colon cancer (100)
Breast cancer (101)

In one study, however, bentonite promoted the growth of lung cancer cells (98). However, these are only cell studies, which does not necessarily mean that bentonite has any medical value in the context of cancer therapy. Many substances that show anti-cancer activity at the cellular level fail in animal and human studies due to lack of efficacy or safety.

How can bentonite be used?

Bentonite is usually available in powder form. A paste with the desired consistency can be prepared from this powder by adding water. Water should be added to the powder little by little to avoid excessive dilution.

Note: Although not yet confirmed by studies, bentonite may react with metal objects and lose its effectiveness. For this reason, the use of plastic or wooden spoons is often recommended.

The applications for external use of bentonite are almost endless. Here are some ideas:

Soothing skin paste: this paste is applied to burns, insect bites and rashes and left to dry on the skin.
Face mask: Bentonite mixed into a paste is applied to the skin of the face and left on for 10 to 20 minutes.
Hair treatment: A bentonite paste is applied to the hair once or twice a week. A little apple cider vinegar and a few drops of hair nourishing oil can be added to this paste.
Baths for softer skin: bentonite is added to bath water to soften the skin and remove toxins that accumulate on the skin.
Homemade soap: although a little more complicated, bentonite can also be mixed with oils and lye to make soap for oily skin.
Toothpaste powder: you can clean your teeth with bentonite to remineralize them, whiten them and kill bacteria.

Before using bentonite on the skin, a skin test for allergies should be carried out first. This involves applying a small amount to the skin and waiting 24 hours to see if skin reactions occur. Bentonite can also be used orally to eliminate toxins from the body and aid digestion. Although there are no official dosage recommendations, unofficial dosage regimes have become established among manufacturers and users. As a rule of thumb, 0.5 to 1 teaspoon of bentonite should be dissolved in a cup of water and this mixture should be drunk once a day. Most clinical studies use up to 3 grams per day.

Side effects and precautions

Bentonite is relatively safe at a dosage of 1.5 to 3 grams per day and only caused mild digestive discomfort (bloating, stomach pain, constipation, diarrhea) in less than 10% of people who took bentonite for two weeks. Half of this dosage did not cause any side effects in children. In both adults and children, bentonite did not reduce the absorption of minerals and vitamins (102, 103, 104). However, excessive oral dosing can lead to nutrient deficiencies. A three-year-old child given adult doses and a cat that ate waste containing bentonite developed severe potassium deficiency with vomiting, constipation, insomnia and weakness (105, 106). Application to the skin has also been shown to be generally safe in clinical trials. However, one test subject experienced a slight, temporary reddening of the skin due to a bentonite lotion (48). High levels of bentonite dust have been associated with an increased incidence of respiratory disease and cell damage in several studies of workers in mines and steel factories. However, potentially toxic impurities (quartz, kaolin, perlite) may also have contributed to this (107, 108, 109, 11). A dental assistant developed severe inflammation of the cornea with reduced vision and sensitivity to light after eye contact with a toothpaste containing bentonite (111).

Although the use of bentonite during pregnancy and lactation has not been studied, bentonite did not reduce mineral absorption and use in pregnant rats (112).

Interactions

Bentonite may bind some drugs - particularly positively charged drugs - and prevent them from entering the bloodstream. Some of these drugs include

Antibiotics (such as tetracycline, trimethoprim and rifampicin antibiotics)
Medications for heart disease (digoxin, quinidine)
Antiallergic drugs (promethazine, chlorpheniramine)
Stimulants (caffeine, amphetamine)
Medication for psychiatric disorders (lithium)
Respiratory drugs (theophylline)
Sedatives (propoxyphene)
Diabetes medication (metformin)

The attending physician should therefore be consulted before taking bentonite if medication is being taken.

Conclusion

Bentonite is a medicinal healing clay. It has a unique structure with a negative charge and different layers that can trap toxins, water and fats. This allows bentonite to bind these substances and remove them from the skin when taken externally. When ingested, bentonite could bind toxins in the digestive tract and help to eliminate them. Scientific research also suggests that bentonite may aid digestion, relieve allergies and promote weight loss, although most of these benefits are still poorly understood.