One of the best performing pages on this blog is “Restore for Gut Health: Danger Will Robinson”. Coal tar has been used topically (on skin) for psoriasis vulgaris for decades , but what about internal consumption of coal tar extract (which appears to be substantially what Restore appears to be “Lignite Extract“).
So what are possible risk with internal consumption?
Potential DNA Damage
- [A association of genetic polymorphisms of XRCC1 and damage levels in workers exposed to coal tar pitch].
- Oral exposure to commercially available coal tar-based pavement sealcoat induces murine genetic damage and mutations .
- Genetic polymorphisms in biotransformation enzymes for benzo[a]pyrene and related levels of benzo[a]pyrene-7,8-diol-9,10-epoxide-DNA adducts in Goeckerman therapy . – this therapy uses coal tar topically for psoriasis.
- [DNA methylation and telomere damage in occupational people exposed to coal tar pitch] .
- Oxidative damage to nucleic acids and benzo(a)pyrene-7,8-diol-9,10-epoxide-DNA adducts and chromosomal aberration in children with psoriasis repeatedly exposed to crude coal tar ointment and UV radiation .
- CYP1A1 gene polymorphisms: modulator of genetic damage in coal-tar workers .
- Final safety assessment of Coal Tar as used in cosmetics . ” Four therapeutic Coal Tar preparations used in the treatment of psoriasis were mutagenic in the Ames assay. Urine and blood from patients treated with Coal Tar were genotoxic in bacterial assays. Coal Tar was genotoxic in a mammalian genotoxicity assay and induced DNA adducts in various tissue types. Chronic exposure of mice to Coal Tar significantly decreased survival and liver neoplasms were seen in a significant dose-related trend; in other studies using mice lung tumors and perianal skin cancers were found. Coal Tar was comedogenic in three small clinical studies. Folliculitis is associated with the prolonged use of some tars. Several published reports describe cases of contact sensitivity to Coal Tar.”
- Should coal tar products carry cancer warnings?
- DNA strand breaks, oxidative damage, and 1-OH pyrene in roofers with coal-tar pitch dust and/or asphalt fume exposure .
A reader forwarded me information to find two published studies. The reader noted that these were not done independently, but by members of the company (Aka CONFLICT OF INTERESTS). I reviewed them and quoted below:
- “The lignite supplement blocked a PT-gliadin dependent decrease in TEER in small intestine and colon cell line membranes. ….demonstrated a statistically significant reduction in apoptosis in RPTCs. Human clinical trials are needed to evaluate the use of RESTORE to support health in gluten-sensitive individuals.”  statistically significant can mean as little as 1% change, some of the confidence intervals as a very high 5% (< 0.05).
- DAR and ZB are shareholders and employees of Biomic Sciences, LLC, the entity that produces the lignite extract supplement used in the study. JJG is a consultant and shareholder of Biomic Sciences, LLC.
- “, the lignite supplement was tested by ultra-sensitive mass spectrometry based heavy metal detection and found to be free of potentially toxic heavy metals or soil minerals [7,8].” — the studies referenced were NOT testing their product and further more, 7 states:
- “Ultrastructural changes of myocardium cells, neurons of sensorimotor cerebral cortex, endothelium of blood microvessels were registered by transmissive electron microscopy in mice receiving rock balm preparations per os. Both stimulating and toxic effects were observed dependently on used concentrations. This necessitates dosage to be strictly observed.” 
- 8 states “One-fifth of both US-manufactured and Indian-manufactured Ayurvedic medicines purchased via the Internet contain detectable lead, mercury, or arsenic.” 
- Their 2017 study “Protective Effects of Lignite Extract Supplement on Intestinal Barrier Function in Glyphosate-Mediated Tight Junction Injury”
- “Initially introduced in a 1962 patent, and commercialized in the herbicide Roundup® in 1976, glyphosate is widely used in both industrial agriculture and residential settings.” — so their claim is that it helps Roundup caused damage.
- ” RESTORE itself is comprised of the 150 mg of Terrahydrite™ lignite extract”, a new fancy TRADEMARK name that was refused on 2017-02-02. Legally, they were required to remove this from all of their websites immediately. They did not.
- ” Further studies are needed to assess potential clinical applications of lignite extract supplements.”
Update — I have even deeper doubts about this product and the operations of the company selling it.
There are ZERO published safety studies on this product — this is essential given the nature of the product. Safety studies should include DNA mutations. There are no published studies on it’s effectiveness on PubMed. This product has the appearance of “snake oil” with placebo effects being likely.
The use of coal tar extracts internally does not appear anywhere on PubMed. Studies exists where occupation working with coal tar results in internal consumption — and all of those presenting very undesired consequences.
I strongly advise against using this product.