Why do some pine nuts cause a bad taste in your mouth that can last for weeks?
Pine Mouth Syndrome: Prolonged Bitter Taste from Certain Pine Nuts
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Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
The reason I make my pesto with walnuts instead of the more traditional pine nuts is not only because walnuts are probably healthier—we’re talkin’ 20 times more polyphenols—but also because of a mysterious phenomenon known as PMS. Nope, not that PMS. “Pine Mouth Syndrome,” characterized by what has become my favorite word of the week, cacogeusia, meaning a bad taste in your mouth. You can get it from heavy metal toxicity, seafood toxins, certain nutritional and neurologic disorders, or from eating the wrong kind of pine nuts. “Termed ‘Pine Mouth’ by the public,” a few days after eating pine nuts, you get this persistent metallic or bitter taste in your mouth that can last for weeks.
Thousands of cases have been reported. Raw versus cooked pine nuts doesn’t seem to matter. Could the cause be some “unidentified toxin present in some varieties of non-edible pine nuts”? “Out of more than 100 different [kinds] of [pine trees, the nuts of only about] 30 are considered to be edible…”
So, pine nut samples from stricken consumers were analyzed, and indeed they all contained nuts from Chinese white pine, which is not reported to be edible. That tree is typically used only for lumber. These are the good ones; these are the bad ones. It’s like a game: good, bad, good, good. You don’t know it’s the Chinese white pine nuts, though, until you put it to the test.
Researchers had a few folks consume six to eight Chinese white pine nuts. Most of the subjects hadn’t ever heard of Pine Mouth syndrome, and boom—they all developed symptoms. We still don’t know exactly what it is in those nuts that causes such a weird reaction. We just know to stay away from those kinds of pine nuts.
So, what kinds of pine nuts do we have on our shelves here? All kinds, apparently, including those associated with pine mouth. Good, good, good, bad, good. So, unsurprisingly, hundreds of cases have been reported in the U.S. as well. Most of the implicated nuts were “[reportedly labeled as] … originating from Asia, and in most cases China.”
Europe actually did something about it and demanded China stop sending them toxic nuts, which they did in 2011. And “this export restriction likely resulted in [less being imported into] the U.S. as well,” given the decline in cases going into 2012. Rare cases still happen, though, as evidenced by an active Facebook group entitled “Damn you Pine Nuts.” The primary reason I made this video is just to allay fears should this ever happen to you. Although there are no proven therapies, Pine Mouth syndrome appears to be benign and just goes away on its own.
Please consider volunteering to help out on the site.
- Bolling BW, Chen CYO, McKay DL, Blumberg JB. Tree nut phytochemicals: composition, antioxidant capacity, bioactivity, impact factors. A systematic review of almonds, Brazils, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts. Nutr Res Rev. 2011;24(2):244-75.
- Munk M. “Pine Mouth” Syndrome: Cacogeusia Following Ingestion of Pine Nuts (Genus: Pinus). An Emerging Problem? J Med Toxicol. 2010;6(2):158-9.
- Flesch F, Rigaux-Barry F, Saviuc P, et al. Dysgeusia following consumption of pine nuts: More than 3000 cases in France. Clin Toxicol. 2011;49(7):668-70.
- Destaillats F, Cruz-Hernandez C, Giuffrida F, Dionisi F, Mostin M, Verstegen G. Identification of the Botanical Origin of Commercial Pine Nuts Responsible for Dysgeusia by Gas-Liquid Chromatography Analysis of Fatty Acid Profile. J Toxicol. 2011;2011:316789.
- Zonneveld BJM. Pine nut syndrome: a simple test for genome size of 12 pine nut-producing trees links the bitter aftertaste to nuts of P. armandii Zucc. ex Endl. Plant Syst Evol. 2011;297:201-6.
- Ballin NZ. A trial investigating the symptoms related to pine nut syndrome. J Med Toxicol. 2012;8(3):278-80.
- Munk MD. Pine mouth (pine nut) syndrome: description of the toxidrome, preliminary case definition, and best evidence regarding an apparent etiology. Semin Neurol. 2012;32(5):525-7.
- Fardin-Kia AR, Handy SM, Rader JI. Characterization of pine nuts in the U.S. market, including those associated with "pine mouth", by GC-FID. J Agric Food Chem. 2012;60(10):2701-11.
- Kwegyir-Afful EE, Dejager LS, Handy SM, Wong J, Begley TH, Luccioli S. An investigational report into the causes of pine mouth events in US consumers. Food Chem Toxicol. 2013;60:181-7.
Video production by Glass Entertainment
Motion graphics by Avo Media
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
The reason I make my pesto with walnuts instead of the more traditional pine nuts is not only because walnuts are probably healthier—we’re talkin’ 20 times more polyphenols—but also because of a mysterious phenomenon known as PMS. Nope, not that PMS. “Pine Mouth Syndrome,” characterized by what has become my favorite word of the week, cacogeusia, meaning a bad taste in your mouth. You can get it from heavy metal toxicity, seafood toxins, certain nutritional and neurologic disorders, or from eating the wrong kind of pine nuts. “Termed ‘Pine Mouth’ by the public,” a few days after eating pine nuts, you get this persistent metallic or bitter taste in your mouth that can last for weeks.
Thousands of cases have been reported. Raw versus cooked pine nuts doesn’t seem to matter. Could the cause be some “unidentified toxin present in some varieties of non-edible pine nuts”? “Out of more than 100 different [kinds] of [pine trees, the nuts of only about] 30 are considered to be edible…”
So, pine nut samples from stricken consumers were analyzed, and indeed they all contained nuts from Chinese white pine, which is not reported to be edible. That tree is typically used only for lumber. These are the good ones; these are the bad ones. It’s like a game: good, bad, good, good. You don’t know it’s the Chinese white pine nuts, though, until you put it to the test.
Researchers had a few folks consume six to eight Chinese white pine nuts. Most of the subjects hadn’t ever heard of Pine Mouth syndrome, and boom—they all developed symptoms. We still don’t know exactly what it is in those nuts that causes such a weird reaction. We just know to stay away from those kinds of pine nuts.
So, what kinds of pine nuts do we have on our shelves here? All kinds, apparently, including those associated with pine mouth. Good, good, good, bad, good. So, unsurprisingly, hundreds of cases have been reported in the U.S. as well. Most of the implicated nuts were “[reportedly labeled as] … originating from Asia, and in most cases China.”
Europe actually did something about it and demanded China stop sending them toxic nuts, which they did in 2011. And “this export restriction likely resulted in [less being imported into] the U.S. as well,” given the decline in cases going into 2012. Rare cases still happen, though, as evidenced by an active Facebook group entitled “Damn you Pine Nuts.” The primary reason I made this video is just to allay fears should this ever happen to you. Although there are no proven therapies, Pine Mouth syndrome appears to be benign and just goes away on its own.
Please consider volunteering to help out on the site.
- Bolling BW, Chen CYO, McKay DL, Blumberg JB. Tree nut phytochemicals: composition, antioxidant capacity, bioactivity, impact factors. A systematic review of almonds, Brazils, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts. Nutr Res Rev. 2011;24(2):244-75.
- Munk M. “Pine Mouth” Syndrome: Cacogeusia Following Ingestion of Pine Nuts (Genus: Pinus). An Emerging Problem? J Med Toxicol. 2010;6(2):158-9.
- Flesch F, Rigaux-Barry F, Saviuc P, et al. Dysgeusia following consumption of pine nuts: More than 3000 cases in France. Clin Toxicol. 2011;49(7):668-70.
- Destaillats F, Cruz-Hernandez C, Giuffrida F, Dionisi F, Mostin M, Verstegen G. Identification of the Botanical Origin of Commercial Pine Nuts Responsible for Dysgeusia by Gas-Liquid Chromatography Analysis of Fatty Acid Profile. J Toxicol. 2011;2011:316789.
- Zonneveld BJM. Pine nut syndrome: a simple test for genome size of 12 pine nut-producing trees links the bitter aftertaste to nuts of P. armandii Zucc. ex Endl. Plant Syst Evol. 2011;297:201-6.
- Ballin NZ. A trial investigating the symptoms related to pine nut syndrome. J Med Toxicol. 2012;8(3):278-80.
- Munk MD. Pine mouth (pine nut) syndrome: description of the toxidrome, preliminary case definition, and best evidence regarding an apparent etiology. Semin Neurol. 2012;32(5):525-7.
- Fardin-Kia AR, Handy SM, Rader JI. Characterization of pine nuts in the U.S. market, including those associated with "pine mouth", by GC-FID. J Agric Food Chem. 2012;60(10):2701-11.
- Kwegyir-Afful EE, Dejager LS, Handy SM, Wong J, Begley TH, Luccioli S. An investigational report into the causes of pine mouth events in US consumers. Food Chem Toxicol. 2013;60:181-7.
Video production by Glass Entertainment
Motion graphics by Avo Media
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Title
Pine Mouth Syndrome: Prolonged Bitter Taste from Certain Pine Nuts
LicenseCreative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Content URLDoctor's Note
Isn’t that strange? Nuts in general, though, are health-promoting. See:
- Walnuts and Artery Function
- Nuts May Help Prevent Death
- Pistachio Nut for Erectile Dysfunction
- Nuts and Obesity: The Weight of Evidence
- PREDIMED: Does Eating Nuts Prevent Strokes?
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