Pine nuts are the seeds of pine trees, and they are not botanical nuts. Pines are gymnosperms, a word from Ancient Greek that means naked seed, so the seeds sit bare between the scales of the cone. The Mediterranean stone pine is slow: its cones ripen three years after pollination, the longest of any pine.
Some pine nuts leave a bitter, metallic taste that shows up 1 to 3 days after eating and can last up to two weeks. It is called pine mouth. Canada’s food inspection agency says it poses no health concern, and not everyone who eats pine nuts gets it. Cases track with nuts of one species, Pinus armandii, which the FAO does not list as an edible pine nut. In French poison center records, the taste began a median of 24 hours after eating and lasted under 14 days in 95% of cases.
An ounce (28 g) of dried pine nuts has 191 kcal, 19.4 g of fat, 3.9 g of protein and 1 g of fiber. Gram for gram, pine nuts have more manganese than any of the 132 foods in our database: an ounce holds 108% of the daily value, plus 42% for copper. They also hold pinolenic acid, a rare fatty acid first found in pine seeds and the reason for studies of Korean pine nut oil capsules. Those trials used oil, not nuts, and the oil’s maker paid for two of them.
Health benefits of pine nuts
The top findings from 18 studies, strongest evidence first
What the stars mean
- Strong. Several randomized trials, pooled in a meta-analysis, point the same way, or regulators (FDA or EFSA) have approved the claim.
- Moderate. Good randomized trials support it, but there are fewer of them, or their results vary.
- Limited. Small, short or single trials, or mixed results. Promising, but it needs confirmation.
Population and lab studies get no stars: they show a link or a mechanism, not proof.
How we rate evidence →- ★★Lower “bad” LDL cholesterol with other nutsAcross 61 trials, each daily serving of tree nuts lowered LDL by 4.8 mg/dL. Pine nuts were not among the nuts tested.
- ★★Fewer heart attacks and strokes with mixed nutsOn a Mediterranean diet with mixed nuts, 3.4% of high-risk adults had a heart attack, stroke or cardiovascular death, against 4.4% on the control diet. The nuts were a mix, not pine nuts alone.
- ★Lower cholesterol in women with metabolic syndromeIn adults with metabolic syndrome, 30 g of mixed nuts a day (pine nuts among them) lowered total and non-HDL cholesterol in women. The trial in Korea was small and lasted 6 weeks.
- ★Pine nut fatty acids raised a fullness hormoneIn 18 overweight women, 3 g of pine nut oil fatty acids (capsules, not nuts) raised the fullness hormone CCK by 60% over 4 hours. In another trial, 2 g of the fatty acids cut food eaten by 9%, but the triglyceride form did not.
- ★Bitter, metallic taste from one pine nut typeSix volunteers ate 6 to 8 Pinus armandii nuts; four got a bitter, metallic taste 1 to 2 days later and two had minor symptoms. No one had symptoms again a year later.
All 18 studies, strongest evidence first
Across 61 trials of tree nuts, each daily serving lowered LDL cholesterol by 4.8 mg/dL, but pine nuts were not among the nuts tested
Meta-analysis of 61 controlled trials (2,582 people) of walnuts, pistachios, macadamias, pecans, cashews, almonds, hazelnuts and Brazil nuts. Each 1-ounce (28.4 g) serving a day also lowered triglycerides by 2.2 mg/dL and apolipoprotein B by 3.7 mg/dL, and the effect was stronger at 60 g a day or more. Pine nuts are not named in the review, so this shows what nuts as a group do, not pine nuts themselves.
A Mediterranean diet with mixed nuts lowered the risk of heart attack, stroke or cardiovascular death (hazard ratio 0.72) in people at high risk
Randomized trial of 7,447 Spanish adults aged 55 to 80, followed for a median of 4.8 years. Major cardiovascular events occurred in 3.4% of the nut group and 4.4% of the control group. The nuts were a mix, not pine nuts alone. The trial was republished after the authors found protocol deviations, and results were similar when 1,588 people with doubtful group assignment were left out.
30 g a day of mixed nuts, pine nuts among them, for 6 weeks lowered total and non-HDL cholesterol in women with metabolic syndrome
Randomized trial in Korean adults with metabolic syndrome, with 60 people in the final analysis. The mix was walnuts, peanuts and pine nuts. Markers of inflammation, oxidative stress and artery function did not change, and the cholesterol gain was reported in women. It was small and short.
3 g of Korean pine nut oil fatty acids with breakfast raised the fullness hormone CCK by 60% over 4 hours and lowered prospective food intake by 36%
Placebo-controlled crossover trial in 18 overweight postmenopausal women, using capsules of pine nut oil, not nuts: 3 g of free fatty acids, 3 g of triglyceride oil or an olive oil placebo. The triglyceride form raised CCK by 22%, ghrelin and PYY did not differ, and the oil’s maker paid for the work.
2 g of Korean pine nut oil fatty acids 30 minutes before lunch cut food eaten by 9%, but the triglyceride form did not
Double-blind crossover trial in 42 overweight women of PinnoThin, a pine nut oil product, against olive oil. Doses of 2, 4 and 6 g of the triglyceride form had no effect, and appetite ratings and macronutrient intake did not change. This was an oil, not nuts, and its maker paid for the work.
Pine nut oil fatty acids in delayed-release capsules raised GLP-1 and lowered ghrelin during a glucose test in healthy adults
Two small crossover studies, in 8 healthy non-obese people and 10 overweight or obese people, who took pine nut oil capsules 30 minutes before a 4-hour glucose test. In the overweight group, 6 g of hydrolyzed oil also raised fullness and lowered prospective food consumption, while blood sugar and insulin fell only a little. This tested an oil supplement, not nuts.
Six volunteers who ate 6 to 8 nuts of the suspect species all developed pine mouth, a bitter, metallic taste
Small trial with 6 volunteers who ate pine nuts suspected of causing the taste problem. Four had the classic bitter, metallic taste 1 to 2 days later, and two had minor symptoms such as dryness and a feeling of enlarged tonsils. Lab tests then showed the nuts were Pinus armandii, and no one had symptoms again a year later.
Each extra 28 g of nuts a day went with a 22% lower risk of dying from any cause, in studies of nuts as a group
Meta-analysis of 20 prospective studies (29 publications) of nuts in general, not pine nuts alone. Per 28 g a day, relative risk was 0.71 for coronary heart disease and 0.85 for total cancer, while stroke (0.93) was not significantly lower. These are links, not proof of cause.
Eating peanuts, pine nuts and almonds once a week or more went with a lower risk of metabolic syndrome over 10 years in Korean adults
Community cohort of 5,306 Korean adults followed for 10 years. The three nuts were counted together as one group, in 15 g servings, so pine nuts alone were not measured. At once a week or more the hazard ratio was 0.72 in men and 0.57 in women.
In 379,310 Korean adults, eating peanuts, pine nuts or almonds once a month or more went with about 10% lower odds of high insulin resistance
Cross-sectional study of health check-up data, so it cannot show cause. The three nuts were counted together in 15 g servings, and the odds ratio was 0.90 for 5 or more servings a week. The link was clearer in women, people with normal blood sugar and people under 40, and was not significant in men, in people with prediabetes or diabetes, or in older adults.
Eating peanuts, pine nuts or almonds 3 or more times a week went with odds of colorectal cancer about 70% lower than eating none, in Korea
Case-control study of 923 colorectal cancer patients and 1,846 controls. The three nuts were one item on a food questionnaire, so pine nuts alone are unknown. Adjusted odds ratios were 0.30 in women and 0.28 in men. Diet was recalled in a questionnaire, and a case-control study cannot show cause.
French poison centers recorded 3,111 cases of lasting bitter taste after pine nuts in under 2 years
Surveillance data from March 2008 to January 2010. The taste began a median of 24 hours after eating and lasted under 14 days in 95% of cases. Raw, cooked and processed pine nuts were all implicated, and the cause was not identified.
The US FDA received 501 reports of lasting bitter or metallic taste after pine nuts, and the cases tracked with the species Pinus armandii
Consumer reports from July 2008 to June 2012. The taste began hours to days after eating, came back with any food or meal, lasted up to a few weeks in some cases and resolved without serious health effects. FDA staff found no clear medical cause in the people who complained and analyzed nuts tied to 15 complaints.
In 10 people with pine nut allergy, 80% of the reactions were severe and 70% were sensitized to pine nut alone
Case series of 10 consecutive teenagers and adults at a Madrid hospital. Two major allergens were identified, and one of them resisted digestion far better than the other. The group was very small.
About 30% of Korean children with pine nut allergy had anaphylaxis
Retrospective review of 42 children at one hospital: 24 with immediate reactions to pine nuts and 18 allergic children who tolerated them. The median age of the allergic group was 3, and 7 of the 24 had anaphylaxis. A blood level of pine nut IgE of 0.40 kUA/L best separated allergic from tolerant children, with a sensitivity of 66.7% and a specificity of 77.8%.
Pinolenic acid, a fatty acid in pine nut oil, switched on two fat-sensing receptors, FFA1 and FFA4, in cells
Cell screen of dietary fatty acids, followed by glucose tolerance tests in mice. Pine nut oil moderately improved glucose tolerance compared with maize oil, and pure pinolenic acid improved it much more. These receptors help control appetite and glucose hormones. No people were tested.
In human immune cells, pinolenic acid cut the inflammation messenger IL-6 by 46% and prostaglandin E2 by 87%
Study in human THP-1 macrophage-like cells plus mouse ear and skin tests. Injected pinolenic acid reduced ear swelling by 15% in thickness, but none was found in the ear tissue, so the authors suspect it acts through cell signaling. It used the pure fatty acid, not nuts.
In mice on a high-fat diet, Korean pine nut oil cut liver triglycerides by 26% compared with soybean oil
Mice ate a 45%-fat diet for 12 weeks with 10% of energy from either pine nut oil or soybean oil. The pine nut oil group gained 10% less weight and had 18% less white fat. This was an oil in mice, not nuts in people.
Who should be careful with pine nuts
Most people can eat pine nuts freely. Take a little care if one of these applies:
- Pine nut and tree nut allergy. Reactions can be severe: 80% of reactions in a case series of 10 people were severe, and 7 of 24 allergic Korean children had anaphylaxis. US labels must name pine nuts as a tree nut, but the EU’s list of eight named tree nuts does not include them, so read ingredient lists and ask an allergist before eating them.
- Pine mouth. A bitter or metallic taste can start 1 to 3 days after eating some pine nuts and fade over a few days to two weeks. Canada’s food agency says it poses no health concern. If it happens, stop eating that batch.
How to choose, store and eat pine nuts
- Portion: an ounce (28 g) has 191 kcal and 1.39 g of saturated fat. Pooled nut trials counted one 28.4 g serving a day, and the Korean trial that included pine nuts gave 30 g a day of a mixed blend.
- Species and labels: importers were advised to trade pine nuts from P. pinea, P. sibirica, P. koraiensis or P. gerardiana. A study of 45 pine nut samples found that most commercial ones from the US market were mixtures of species, so a label may not settle it.
- Pine nut oil capsules: the appetite trials gave 2 to 6 g of a pine nut oil product, either with a light breakfast or 30 minutes before a meal or glucose test. No trial tested whole pine nuts for appetite.
Shelled pine nuts go rancid quickly, so buy small amounts and keep them airtight. StillTasty gives 1 to 2 months in the fridge and 3 to 6 months in the freezer for best quality, and says a bitter taste often means the nuts have gone off.
Sources
- Questions and answers regarding food allergens, including the Food Allergen Labeling requirements of the Federal Food, Drug, and Cosmetic Act (Edition 5): guidance for industry. US Food and Drug Administration. 2025.
- Annex 2: allergen labelling, response of the European Union. European Commission, Codex Committee on Food Labelling. 2018.
- Cabanillas B, Novak N. Allergic reactions to pine nut: a review. J Investig Allergol Clin Immunol. 2015.
- Bitter or metallic taste in pine nuts. Canadian Food Inspection Agency. 2021.
- Destaillats F, Cruz-Hernandez C, Giuffrida F, et al. Identification of the botanical origin of commercial pine nuts responsible for dysgeusia by gas-liquid chromatography analysis of fatty acid profile. J Toxicol. 2011.
- 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.
- Shelled pine nuts: how long do pine nuts last out of the shell? StillTasty.
- Qualified health claims: letter of enforcement discretion, nuts and coronary heart disease (Docket No. 02P-0505). US Food and Drug Administration. 2003.
History of pine nuts
Pine nuts come from pines, which are gymnosperms, so the seed is not wrapped in a fruit. The FAO counts 29 pine species with edible nuts, and 20 of them are traded. Korean pine, from northeast Asia, is the most important species in international trade, and stone pine is the main species in Europe.
People ate them long before farming. A hearth in Gorham’s Cave in Gibraltar, about 60,000 years old, held pine nut remains and cone scales, and charcoal in it points to stone pine. The team that excavated it says Neanderthals may have eaten the nuts and used the resin-rich cones as kindling.
Stone pine has been planted for its nuts for thousands of years. The Greek writer Theophrastus, who lived from about 372 to 287 BC, called it the domestic pine. A papyrus from the 2nd century AD lists 16 pine cones supplied for a sacrifice to the Egyptian river god Nilos, and in Rome, stone pines lined roads such as the Via Appia.
In North America the nuts come from pinyon pines. Shoshone, Paiute, Navajo, Pueblo, Hopi and Washoe peoples and the Hispano communities of New Mexico harvest them, and the Navajo used them in trade. Pinyon cones mature near the end of their second summer, and harvesters dry them in the sun for about 20 days until they open.
Pesto made pine nuts famous. Giovanni Battista Ratto’s 1863 cookbook La Cuciniera Genovese has a basil sauce with pine nuts, and the word pesto comes from the Genoese verb for pound. Pesto’s popularity since the 1990s raised the nuts’ profile in the US, especially on the West Coast.
Today China, Russia, North Korea and Pakistan are the largest exporters. Destructive harvesting, such as breaking off branches, has cut production capacity in China and Russia. Trade took another hit from 2008, when pine mouth reports began in France and the US, and researchers traced cases to Pinus armandii. In Europe, a fungus spread by an introduced insect has also hurt pine nut production in Mediterranean Europe.
Sources
- Pine nut. Wikipedia.
- Pinus pinea. Wikipedia.
- Pinus pinea (pinheiro manso). The Gymnosperm Database.
- Pine cones and pine nuts in Gorham’s Cave. Gibraltar National Museum.
- Pesto. Wikipedia.
- Awan HUM, Pettenella D. Pine nuts: a review of recent sanitary conditions and market development. Forests. 2017.
- Flesch F, Rigaux-Barry F, Saviuc P, et al. Dysgeusia following consumption of pine nuts: more than 3000 cases in France. Clin Toxicol (Phila). 2011.
- Destaillats F, Cruz-Hernandez C, Giuffrida F, et al. Identification of the botanical origin of commercial pine nuts responsible for dysgeusia by gas-liquid chromatography analysis of fatty acid profile. J Toxicol. 2011.
Frequently asked questions about pine nuts
Are pine nuts good for you?
They can be a useful food in small amounts, but pine nuts have little direct evidence. An ounce (28 g) has 191 kcal, 3.9 g of protein, 108% of the daily value for manganese, 42% for copper and 18% for vitamin E. Trials of eight other tree nuts found a 4.8 mg/dL drop in LDL cholesterol per daily ounce, but pine nuts were not among them, and their own trials are small oil studies.
What is pine mouth and how long does it last?
Pine mouth is a bitter or metallic taste that starts 1 to 3 days after eating certain pine nuts. It lasts a few days to two weeks, and Canada’s food agency says it poses no health concern. French poison centers logged 3,111 cases, and 95% of them lasted under 14 days. The cause is not confirmed, but FDA staff found that cases tracked with Pinus armandii.
Are pine nuts actually nuts?
No, they are seeds of pine trees, and pines are gymnosperms, plants whose seeds are not enclosed in a fruit. Allergy rules still treat them as tree nuts in the US, where the FDA lists pine nut among them. The EU’s list of eight named tree nuts leaves them out.
Why are pine nuts so expensive?
The trees are slow and the work is mostly by hand. Stone pine cones ripen three years after pollination, the longest of any pine. In Spain, workers climb trees and collect 400 to 600 cones a day, the cones are dried in the sun, and machines remove the hard shell, which adds cost. About 15 to 22 kg of nuts come from 100 kg of cones.
Do pine nuts help with weight loss?
Not shown. The appetite studies used capsules of pine nut oil, not nuts. In 42 overweight women, 2 g of the oil’s fatty acids cut food eaten at lunch by 9%, and in 18 women, 3 g lowered self-rated prospective food intake by 36%. Pine nuts have 191 kcal an ounce, and no trial tested whole pine nuts for weight.
How many pine nuts can you eat a day?
No study sets a pine nut limit. Pooled nut trials counted one ounce (28.4 g) a day, the Korean trial with pine nuts gave 30 g a day of a mixed blend, and the FDA claim speaks of 1.5 ounces a day of most nuts. An ounce of pine nuts has 191 kcal, so the amount adds up. If you get pine mouth, stop eating that batch.
Are pine nuts a common allergen?
They are a recognized tree nut allergen in the US, and reactions can be severe. In 10 people with pine nut allergy, 80% of reactions were severe, and 7 of 24 allergic Korean children had anaphylaxis. A review found little IgE cross-reactivity with other commonly eaten nuts, but ask an allergist before eating other nuts.
Are pine nuts high in protein?
They have a moderate amount: 3.9 g an ounce (28 g), or 13.7 g per 100 g. Protein gives 8% of the calories and fat gives 86%. Lysine is the limiting amino acid, and the protein scores 77 out of 100 for completeness on our page.