Autumn is here and with it comes a lot of baked goodies and pumpkin spice. This toxicity segment is dedicated to most of the culinary herbs and their potential side effects. Many of the herbs listed here are regarded as safe by the general public, but this is far from reality. A majority of people would argue that since you use spices in low doses that their health effects are negligible and can be considered as safe to use. In my opinion, anything that even has the slightest potential to be toxic or contains toxic compounds is toxic. While all these herbs/spices have varying levels of toxicity, each person feels their effects differently. It’s mostly the content of their essential oils which are known to produce their significant flavors and smells. Compositions of essential oils are extremely different depending on numerous parameters related to the plant’s cultivation, harvest, and storage. This is just a general guideline and you may find some of these less toxic than what I make them to be, but that doesn’t mean they are safe for all people.

A person with cancer might feel awful after consuming tarragon containing food, but it all depends on the condition of each individual. I am not saying that all spices should be avoided, but there should be a limit to them. That’s precisely what I am trying to determine in this segment. Every single spice on this list is highly regarded by some culture (to the point of being considered sacred) and they are grown in heaps, so it’s a billion-dollar industry for sure. It’s really interesting to see how most of the spices are toxic in some way or another. Without further ado, here’s the list, starting from the worst ones.

Star anise (fruit) [Illicium verum]

Star anise (or badian) generally contains more trans-anethole than anise seed, so you are in for a toxic treat. Other toxic compounds include estragole, cis-anethole and veranisatins A-C. Veranisatins are capable of causing convulsions and at higher doses even death 1. Boiling for longer periods increases the concentration of veranisatins making the decoction even more toxic 2.

Trans-anethol has been shown to produce non-malignant, but also malignant lesions in rats, especially liver lesions 3. It is rapidly absorbed upon ingestion and metabolized in liver. High doses are very irritating 4.

A study with rats that were fed anethole has found that it can increase liver and thyroid weight, deplete liver glycogen and reduce food intake. 4

Star anise is often contaminated or confused with Japanese star anise (Illicium anisatum) which contains anisatins, compounds that are similar to veranisatins and act as GABAA receptor agonists, making them potent neurotoxins. 2

There have been several cases of poisoning in infants with neurological and digestive symptoms. 2

Final verdict: Badian fruit is more neurotoxic and deadlier than anise seed, so avoid this at all costs due to possibility of death. If you really wish to use it, use the dosage of 1 star for 250 ml liquid. I would also suggest not boiling it as infusion would be less toxic.

Anise (seed) [Pimpinella anisum]

Anise seeds are surprisingly very toxic. They contain a variety of toxic compounds, namely trans-anethol, cis-anethole, estragole, coumarins, eugenol, anisaldehyde, scopoletin and many others depending on the variety or cultivar 5. Trans-anethole is the major constituent of the essential oil and its concentration can definitely reach above 90%.

It might also be estrogenic in nature, but the studies regarding that are inconclusive (as most studies regarding hormonal herbs are). It has also been shown that trans-anethole might have antifertility effects, more specifically abortifacient effects. 4

Anise oil has potent neurotoxic effects as ingestion of just 1-5 ml of anise oil might cause vomiting, seizures, pulmonary edema and nausea. 4

Scopoletin is a known inhibitor of thyroid function 6.

Final verdict: I have experienced significant neurotoxicity, headaches, heart pain, renal pain, lower back pain and pain of the spleen. Anise seeds are also thyroid disruptors. Avoid it at all costs as it can be deadly.

Nutmeg (seed) [Myristica fragrans]

Nutmeg is commonly consumed in powdered form of the seed kernel. Another spice called mace is also isolated from this plant, but I won’t go into detail about it as it’s not that commonly used. There is a huge amount of toxic compounds present in the seed or its essential oil, these include myristicin (methoxysafrole), safrole, elemicin, eugenol, isoelemicin, isoeugenol, methoxyeugenol, methyl eugenol, toluene and sabinene. 7,8

Myristicin is a narcotic, structurally similar to other hallucinogenic compounds and seems to act in an anticholinergic manner, similar to poisons isolated from nightshade family. Myristicin is also an inhibitor of monoamine oxidase while other constituents are serotonin agonists. Toxicity is mainly related to cardiovascular and central nervous system. 9

Large doses of myristicin cause fatty degeneration of liver 9.

Even though nutmeg is considered to be a rich source of myristicin, its concentration in essential oil is not as high as expected. According to one source, seed contains approximately 10% of essential oil of which myristicin comprises only 5% 10. There are other herbs and spices that contain much more myristicin. The toxicity of nutmeg is mostly due to the synergistic effects of several toxic compounds (this is a very common pattern in spices).

Overdose of nutmeg powder produces symptoms of palpitations, tachycardia, paranoia, anxiety, miosis, paresthesias, mydriasis, drowsiness, nausea, dry mouth, restless and agitation. Other symptoms of intoxication include facial flushing, delirium, hypertension, blurred vision, chest pain, agitation, ataxia, nystagmus, vertigo, tremors, distortion of sensory perception, headaches, weakness, feelings of warmth or coldness and finally death. 11

Dosage of 5 g (approx. 1 tsp.) can be considered as safety threshold, but toxicity may occur even at lower doses. 9 Death can occur at overdose.

The main safety problem is that there is no way of knowing what toxic compounds (especially their metabolites) may await you, so even though there are some varieties low in myristicin, this fact is properly compensated for by other toxic compounds.

Ingestion of nutmeg has also caused teratogenic effects in rats 10.

Safrole, just like myristicin, causes DNA adducts in liver 10.

Final verdict: Nutmeg contains too many toxic compounds, so its regular consumption is like playing a Russian roulette with your body. It’s highly unpredictable even though you may think there is very little essential oil remaining in the powder.

Cinnamon (bark) [Cinnamomum cassia /verum]

There are two main types of cinnamon that are sold commercially, namely Chinese cinnamon (Cinnamomum cassia) and Ceylon cinnamon (Cinnamomum verum). Chinese cinnamon, also known as cassia cinnamon, is more toxic than Ceylon cinnamon due to a higher concentration of coumarins. However, Ceylon cinnamon is far from non-toxic. The composition of their essential oil is mostly the same, so the only difference between is the amount of coumarins. The composition of their essential oils is dominated by cinnamaldehyde (over 60%), cinnamyl acetate and eugenol. Cassia cinnamon seems to contain more cinnamaldehyde (in both its trans and cis forms) than Ceylon cinnamon.

Cinnamon has been implicated as the causative factor of hepatotoxicity in several studies of TCM and Kampo preparations 12. Cinnamaldehyde may also be carcinogenic and teratogenic.

Final verdict: Avoid cinnamon if you can. Use only very small doses (less than 1 tsp. per day). My personal experience with 2 tsp. of cinnamon were pain in stomach, liver, and kidneys coupled with irritated mucosal membranes.

Cloves (flower buds) [Syzygium aromaticum]

Most of the toxicity of cloves is attributed to eugenol, the dominant constituent of essential oil. Eugenol is present in all parts of the plant and sadly, it’s also present in all varieties in high percentages. Clove buds might also contain salicylic acid, methyl salicylate, and tannins. 13

Cloves are very irritating and allergenic. Be wary when using clove essential oil as you can expect allergic rashes for a long period of time. Essential oil can produce these awful stains that you will never wash off from acrylate baths.

Mice fed with high doses of alcoholic and aqueous extracts of cloves have experienced a decrease of sperm counts, motility, density, testosterone and increase of estradiol. 14

Final verdict: Avoid them if you can. While eugenol may not be as toxic as cinnamon’s cinnamaldehyde and coumarins, I would still use other alternatives.

Tarragon (leaf) [Artemisia dracunculus]

Tarragon, as most of the spices, is highly variable in the composition of its essential oil, but the prevalent toxic constituents, estragole and methyl eugenol, have been found to be present in essential oil up to 82% and 39%, respectively. 15

Tarragon may also contain elemicin, sabinene, trans-anethole, cis-anethole, methylisoeugenol, isoelemicin, coumarins (scopoletin, esculetin, coumarin and others) 15. As evident, this makes tarragon highly unpredictable.

Estragole (dominant in French tarragon) is a known indirect carcinogen as its genotoxic effects are mostly attributed to estragole’s genotoxic metabolites. 15

Methyl eugenol is carcinogenic, capable of inducing tumors of liver, stomach, kidneys, neuroendocrine system, mammary glands, skin and mesothelioma. It is directly genotoxic and carcinogenic due to its insufficient metabolic activation. 15

Final verdict: Stay away from this herb. You may experience pain in the stomach, thyroid, liver, kidneys and intestines. I have also experienced drowsiness at high doses (6 tsp. in 500 ml of water).

Marjoram (leaf) [Origanum majorana]

Marjoram contains high levels of arbutin, a highly toxic compound that’s found in a variety of plants, but most famously present in bearberry leaf. Arbutin alone is toxic, but its metabolite hydroquinone even more so. Hydroquinone is mutagenic, genotoxic, carcinogenic, hepatotoxic, nephrotoxic. Hydroquinone might be one of the causes of leukemia as well. 16

Marjoram not only contains arbutin, but also hydroquinone and methyl arbutin 17. Once again, arbutin content hugely depends on your marjoram variety, but this doesn’t mean you should gamble as most varieties contain arbutin. This is honestly one of the worst spices for someone suffering from cancer, especially colon cancer.

Other toxic compounds that might be present in marjoram are anethole, eucalyptol, vitexin and eugenol. 17

Final verdict: Arbutin hardly has any benefits, contrary to the popular belief, so avoid it at all costs. The risk of arbutin causing DNA damage, especially in your intestines is quite high. I have personally experienced thyroid, hip, colon, ear and renal pain.

Basil (leaf) [Ocimum basilicum]

Most, if not all, basil varieties contain estragole and methyl eugenol, both of which are toxic. I won’t go into the detail into other toxic constituents of the essential oil since these highly depend on several factors related to the plant growth, harvesting and its storage. Every variety of basil can be different in many aspects, but estragole and methyl eugenol seem to be the prevalent constituents. If you have a basil that contains very little estragole then chances are the levels of methyl eugenol are quite high, but it’s not a full-proof.

Estragole (also known as methyl chavicol) and methyl eugenol have been found to be carcinogenic and genotoxic. Chronic consumption of basil may potentially increase your risk of developing liver and stomach cancer. Methyl eugenol increases incidence of liver and stomach neoplasms.

Allspice / pimento (fruit) [Pimenta dioica]

The main constituent that gives this spice its flavor and scent is eugenol. The concentration of eugenol in essential oil can reach up to 80% 18, making this on par with cloves when it comes to toxicity. Unripe allspice berries might also contain methyl eugenol 19. Although LD50 was found to be more than 7.5 g/kg BW 20, I do not believe it’s that safe to use considering how many side effects eugenol can bring to the table (quite literally).

Final verdict: High doses were neurotoxic, irritating and disrupted thyroid function.

Fenugreek (leaf/seed) [Trigonella foenum-graecum]

Alkaloids (trigonelline, choline, carpaine) and volatile compounds are responsible for the awful bitter flavor of fenugreek. The seed may contain thyroid disruptors – orientin, vitexin and isovitexin. Fenugreek is known to be a galactagogue, indicating potent estrogenic effects. 21

Saponins constitute roughly 5% of the seeds with two major steroidal sapogenins being yamogenin and diosgenin. These saponins are known for their hormonal effects, exhibiting antifertility and teratogenic effects. 22

Trigonelline is degraded to niacin and other pyridines upon roasting, accounting for most of the bitter flavour. 22

Clinical studies have shown that consumption of fenugreek may produce symptoms of gastrointestinal discomfort. High doses of fenugreek in mice have also produced symptoms of tremors, twitching, writhing, convulsions, rapid respiration and excitation. This suggests that negative effects of fenugreek are mostly concentrated in gastrointestinal tract and central nervous system. Hypoglycemia, allergic reactions, flatulence, diarrhea, dizziness and dyspepsia have all been reported in humans. 22

Fenugreek seed has been linked with detrimental effects on male fertility, causing decreased weights of reproductive organs, decreased sperm counts, abnormalities and histopathological changes in testes. This suggests that fenugreek causes DNA damage in male reproductive system. Not only that, but fenugreek also decreases serum testosterone and LH. These effects are very well-researched and there can be no doubt about its toxic effects on humans as well. 22

Even though fenugreek is popular among lactating women, they should be wary regarding its use. In female rats, the seeds have been shown to cause decrease of hormonal levels, decrease of uterine and ovarian weights and reduction of folliculogenesis. 22

Fenugreek either decreases or increases levels of estrogen, but it’s most likely the former. All in all, this makes fenugreek inappropriate for lactating women regardless of its incredibly strong effects on lactation as it’s highly likely that the constituents will get into your breast milk and ultimately causing mutations in your babies.

There are several studies indicating that fenugreek seeds are highly teratogenic, even capable of producing liver and kidney abnormalities. Rats fed fenugreek leaves have also experienced their teratogenic effects. 22

In children, fenugreek has been shown to increase the risk of encephalopathy and its symptoms, such as anencephaly, hydrocephalus and spina bifida. The seeds also alter neurological development and behavior, making it a potent neurotoxin for prenatal and postnatal women. 22

Fenugreek also has allergenic properties and can potentiate the effects of medicine, especially warfarin. 22

Other studies have shown that fenugreek can cause thyroid disruption, necrotic effects in liver and kidneys and changes of hematological parameters. This is most likely due to the presence of coumarins which are highly toxic to liver and kidneys. 22

Final verdict: This plant is extremely toxic to both women and men. Avoid it if you can, it doesn’t even taste that good.

Fennel (seed) [Foeniculum vulgare]

Essential oil of fennel mostly contains trans-anethole, with fenchone and estragole as minor constituents. 23

Fenchone is potentially hepatotoxic, decreasing levels of hepatic enzymes. 24

Anethole’s derivates have also been linked with estrogenic effects. 23

Final verdict: Avoid it at all costs.

Black pepper (fruit) [Piper nigrum]

This most likely applies to white pepper, red/orange and green pepper, since they all stem from the same plant, the difference is the processing of either ripe or unripe fruit.

The spiciness of this fruit is attributed to piperine, one of the major constituents of this plant. Piperine at the dose of 25 mg/kg and higher has been found to cause irritation, drowsiness, paralysis and death in rats. 25

Other toxic compounds that may be present in lower concentrations are myristicin, sabinene, eucalyptol, trans-anethole, safrole, camphor, methyl eugenol and eugenol. 26

May irritate urinary tract and high doses may cause abdominal heat, burning, thirst, vomiting, fever, convulsions.

Alcoholic extract may cause increased tissue lipid peroxidation in liver and thyrotoxicosis with increased concentrations of thyroid hormones T3 and T4. The water extract did not produce such symptoms. 27

Piperine also causes reversible imbalance of serum FSH, LH, SHBG and testosterone (both in testis and serum). Piperine may have anti-fertility properties on men. 28

Piperine is known for its incredible synergistic properties, increasing bioavailability of other compounds. This may, however, be a double-edged sword if you are taking any medication.

Final verdict: If you need your food to be spicy, go with chilli instead.

Sage (leaf) [Salvia officinalis]

Essential oil of sage may contain α-/ß-thujone, eucalyptol, and camphor. 29 These compounds are mostly neurotoxic, but teratogenicity, hepatotoxicity, and nephrotoxicity may be associated with them as well.

Thujone is a GABA antagonist causing excitations and convulsions. α-thujone is more toxic than ß-thujone, causing seizures, convulsions and ultimately death. Chronic studies of thujones have found that they can increase incidence of lesions in spleen, kidneys, pituary glands, brain. 30

Camphor is a highly toxic compound, capable of causing damage of kidneys, spleen, ovaries and liver 31. It has also been linked with brain cell damage with toxic effects on hippocampus and cerebral cortex 32.

Overdose may cause symptoms of vomiting, seizures, excessive salivation, gastric burning, dizziness, sweating, rapid breathing, loss of consciousness, cyanosis, vertigo, hot flashes, allergic reactions, tachycardia, and swollen tongue 33.

Sage also potentiates the effects of carbon tetrachloride, a common hepatotoxin that is used for hepatotoxicity studies.

Final verdict: The benefits of this herb do not outweigh the risks.

Rosemary (leaf) [Rosmarinus officinalis]

Rosemary oil may contain camphor and eucalyptol, their concentration highly dependent on rosemary’s chemotype.

Final verdict: Rosemary leaf is a strong thyroid disruptor.

Thyme (leaf) [Thymus vulgaris]

Thyme’s constituents may bind to estradiol and progesterone receptors, indicating its hormonal effects. 34

Final verdict: I found thyme to be an endocrine disruptor, so use it with caution.

Parsley leaf [Petroselinum crispum]

Myristicin (63.9 %) and apiole (14.4 %) were found to be major constituents of the essential oil from parsley growing in Cuba 35. Another study focusing on both the curley-leaf and flat-leaf parsley found that the former had a higher concentration of myristicin while essential oil of the latter was predominantly composed of apiole 36. Generally speaking, myristin or apiole will either be one of the major constituents or second highest in concentration with variations of ß-phellandrene and 1,3,8-p-menthatriene.

Apiole and myristicin possess low solubility in water, but excellent solubility in alcohol.

Myristicin is hepatotoxic (causing liver cancer) and neurotoxic 36.

Parsley may also contain coumarins, namely bergapten and oxypeucedanin, 8-methoxypsoralen, imperatorin, isoimperatorin, psoralen, xanthotoxin. The concentration of coumarins are quite low.

Final verdict: Your experience with parsley highly depends on its composition, but I found mine to have negative effects on thyroid and kidneys. Use celery leaf instead.

Saffron (flower) [Crocus sativus]

Saffron contains a huge amount of volatile and non-volatile compounds. Safranal (responsible for its odor) and crocin (responsible for its color) are the main toxic compounds of saffron. 37

Studies regarding the toxicity of saffron are mixed. Ethanolic extract has been shown to increase white blood cell counts and decrease hemoglobin, hematocrit and red blood cell counts. This was also accompanied with elevated urea, uric acid, ALT and AST, suggesting that it’s nephrotoxic and hepatotoxic. 37

Crocin has been found to increase platelets and creatinine while a decrease of ALP, albumin, alveolar size have also been observed. This suggests that saffron causes lung injury as well. 37

In another study, saffranal has been capable of inducing histopathological changes of kidneys and lungs. 37

Saffron, saffranal and crocin have all been shown to be teratogenic. 37

Final verdict: Considering how expensive and hard to get this flower is, it’s very unlikely that its usage will cause you any grievous symptoms, but use it with care.

Dill (weed) [Anethum graveolens]

The main constituents of dill essential oil should be carvone and limonene, α-phellandrene 38–40.

Dill weed may contain up to 28.2 % of myristicin 38. Other toxic compounds that may be present are eucalyptol, anethole, anisaldehyde, apiole and dill apiole 39–41.

Final verdict: It all depends on variety of your dill weed.

Bay (leaf) [Laurus nobilis]

There is a common misconception that bay leaves are toxic when consumed. Technically, they are not toxic, it’s just they might irritate your gastrointestinal tract due to their rough texture. Bay leaves’ smell is most likely due to the presence of eucalyptol (1,8-cineole). Eugenol, methyl eugenol, and sabinene have also been reported to be constituents of the essential oil.

The toxic effects of eucalyptol are mostly focused on respiratory system. Rats injected with the lethal dose of eucalyptol have experienced symptoms of hypoactivity, cyanosis, irregular breathing, convulsions and stupor. LD50 of 1,8-cineole has been determined to be 3.849 g/kg which is quite high. 42

With regular use, eucalyptol has also caused histopathological changes in liver and kidneys 42.

Final verdict: I wouldn’t inhale any oil containing eucalyptol on a regular basis, but I think it should be fine in cooking. It shouldn’t be that toxic if most of the essential oil is evaporated.

Paprika / Cayenne pepper (fruit) [Capsicum annuum]

Paprika and cayenne pepper both stem from the same plant, but different varieties (or cultivars). The spiciness of cayenne pepper stems from the compound capsaicin. Capsaicin is fat soluble and very well-absorbed from skin, so definitely don’t touch sensitive areas when working with peppers.

Topical use of capsaicin-containing preparations may cause irritation, burning and stinging pain. In contact with eyes, it may produce symptoms of conjunctivitis, tearing and blepharospasms. 43

Internal use may cause vomiting, abdominal pain, diarrhea and nausea. 43

Final verdict: Paprika is excellent, but it might be a bit irritating if it contains ground seeds. Cayenne pepper is better than chili due to its lower capsaicin content

Chili (fruit) [Capsicum spp.]

Capsaicinoids found in chili peppers may be extremely irritating, to the point of intense burning and pain.

Final verdict: Use in moderation, depending on how much you can handle.

Ginger (root) [Zingiber officinale]

Ginger may feel like it’s irritating to your gastrointestinal tract, but that’s nothing compared to piperine. I find it to be safe, just don’t use it in alcohol as it had a negative effect on thyroid (most likely due to some compounds in essential oil). I haven’t come across any toxicology studies that found it to have toxic effects on human body.

Final verdict: Ginger is extremely safe with LD50 over 250 g/kg. Feel free to use this wonderful spice that offers numerous benefits. You might experience some side effects, but ginger is far from deadly, unlike so many other spices.

Mustard (seed) [Brassica nigra/juncea/hirta]

You can expect all types of mustard seed to contain isothiocyanates (mostly allyl isothiocyanate) which have been linked with hepatotoxicity, nephrotoxicity, teratogenicity, and carcinogenicity. Isothiocyanates are also potent irritants of skin, mucosal membranes and thyroid gland.

Final verdict: Not worth the risks.

Oregano (leaf) [Origanum vulgare]

Oregano was found to have an affinity for estrogenic receptors 44, but I did not find it to be hormonal at all.

Final verdict: Oregano is one of the good ones. It might contain tannins which are concerning and high doses may be irritating due to carvacrol present in the essential oil, but overall it’s a very decent herb when used in low doses.

Turmeric (root) [Curcuma longa]

Despite the myriad of benefits that turmeric offers, there are still some issues to consider.

Turmeric has been shown to be toxic to male reproductive organs. This is most likely due to the high concentration of curcumin. Aqueous and alcoholic extracts can reduce sperm count and motility, reduce the weight of testis and epididymis, and increase the number of abnormal spermatozoa. Turmeric may also decrease antioxidant content in testis and serum levels of testosterone and DHEA. 45

In female rats, turmeric extracts have decreased FSH and LH levels, which was accompanied by the suppression of estrus phase. This proves that turmeric may act as an anti-fertility agent in both women and men. 45

Turmeric can also be teratogenic and embryotoxic at high concentrations. 46

Final verdict: Turmeric is not that bad, just don’t use high doses since they can be a bit irritating (maybe irritating is the wrong word, but it feels weird) to gastrointestinal tract.

Black cumin (seed) [Nigella sativa]

Black cumin is a wonderful addition to your kitchen. I am not aware of black cumin having any negative effects on human body. There are so many studies confirming its incredible anticancer, hepatoprotective and nephroprotective benefits.

Final verdict: It’s excellent, but keep it in mind that it might be a bit irritating when using a decoction or infusion of ground seeds. I would stick to using whole seeds, but low doses of ground seeds might be fine as well.

Caraway / cumin (seed) [Carum carvi / Cuminum cyminum]

Caraway is often mistaken for cumin (Cuminum cyminum), but it’s so much better than cumin. Caraway essential oil mostly contains limonene and carvone, with minor constituents being carvacrol, α-pinene, linalool, carvenone and others. None of these compounds are highly toxic. Cumin’s main constituents are cuminaldehyde, limonene, α-/ß-pinene, γ-terpinene. Cumin may contain toxic eucalyptol and safranal. 47

Both caraway and cumin have been found to be estrogenic, potentially modulating levels of FSH, LH and estrogen. 47

Final verdict: Caraway may have potential estrogenic/hormonal effects, so use it with caution. Don’t grind it as you might experience higher thyroid disruption. I haven’t tested cumin yet.

Celery (leaf) [Apium graveolens]

The aroma of celery leaf is mostly due to the presence of limonene, ß-myrcene, 4-terpineol and ß-ocimene. 48 It might also contain myristicin.

Celery is also a common allergen for some people.

Final verdict: I found both the root and the leaf to be extremely good, having several health benefits. Celery leaf was much better than parsley leaf, so it’s a good alternative if you can’t use that.

Chives (aerial parts) [Allium schoenoprasum]

Chives are still criminally under-researched when it comes to their toxicity. If there are any toxic compounds to blame, it’s most likely the numerous sulphur compounds (mostly sulphides) present in it.

Final verdict: I found chives to have a negative effect on thyroid and kidneys.

Savory (leaf) [Satureja spp.]

Savory species are rich in carvacrol, similar to oregano. You can expect irritation, but no highly toxic effects.

Final verdict: Good in small doses.

Coriander (seed) [Coriandrum sativum]

Coriander is very safe to use; no serious side effects or histopathological changes have been reported for seed extract.

Final verdict: Coriander is excellent, but it may be a bit irritating at high doses (especially when in its ground form). Feel free to use it as you wish.

Cardamom (seed) [Elettaria cardamomum]

Even though cardamom essential oil has been found to contain a variety of compounds (with eucalyptol being one of the major constituents), its methanolic extract and essential oil are relatively non-toxic. 49

Final verdict: High doses of cardamom (especially in the ground form) are potential thyroid disruptors, but cardamom offers too many health benefits to pass on it. Use it in low doses and you will be fine. It’s one of the best spices that are out there.

Galangal (root) [Alpinia officinarum]

I am not aware of any toxicological studies that found galangal to be toxic to organs or hematology.

Final verdict: Use it as much as you want. High doses of galangal may be a bit disruptive to the thyroid, but other than that, I find it really safe.

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