Goji berry

What it is

Goji berries are the fruit of Lycium barbarum, a thorny deciduous shrub in the nightshade family (Solanaceae). The berries are most often eaten dried, or used to make juice, tea, or wine, and are incorporated into foods like yogurt and granola; they have a long history of use in Chinese traditional medicine, where they are known as Gouqizi.

What the research says

Goji is marketed for general well-being, antioxidant status and eye health. A small industry-linked randomized trial reported improvements in self-rated energy, mood and sleep, though the same trial found no differences in any objectively measured outcome. A separate small unmasked randomized pilot trial found macular pigment optical density rose in the goji group over 90 days. The well-being trial's own authors write that “further research is indicated to confirm and extend knowledge of the potential effects of Lycium barbarum upon human health.”

Evidence grade: Limited evidence.

What goes wrong

A case report describes one warfarin patient who developed hematuria after drinking a small amount of Gouqizi (goji) wine. (Source 1)

• Case report, Certainty not rated.
• Size: 1 patient.
• Who: A 65-year-old man on long-term warfarin for a prosthetic heart valve.
• How long: after a single 20 mL dose of goji wine.
• Result: Hematuria with an abnormal urinary red blood cell count of 33,201.5/μl against a normal range of 0 to 23/μl.
• Funding: not applicable.

Limit of this finding: This is a single case, not a rate. It shows what happened to one person already taking warfarin; it does not tell you how often goji affects people on anticoagulants, or whether it affects people who are not.

an abnormal urinary red blood cell count of 33201.5/μl (the normal range is 0–23/μl)

The authors of that case report conclude that large doses of Gouqizi (goji) can significantly enhance warfarin's anticoagulant effect, while noting the mechanism is not established. (Source 1)

• Case report, Certainty not rated.
• Size: 1 patient.
• Who: A warfarin-treated patient.
• How long: not applicable.
• Result: Authors attribute a significant enhancement of warfarin's anticoagulant action to doses above 6 to 12 g of Gouqizi, and state that the mechanism needs further study.
• Funding: not applicable.

Limit of this finding: This conclusion is drawn from one patient. The authors themselves say the mechanism of the interaction still needs to be studied.

large doses (more than 6–12 g) of Gouqizi can significantly enhance the anticoagulant action of warfarin

A case report describes toxic hepatitis attributed to goji berry consumption in one patient, which its authors describe as the first such published case. (Source 2)

• Case report, Certainty not rated.
• Size: 1 patient.
• Who: A 24-year-old woman.
• How long: not stated.
• Result: Jaundice at the sclera, right upper quadrant tenderness and high liver function tests, with other causes excluded.
• Funding: not applicable.

Limit of this finding: This is one case, not a rate. The authors call it the first published report of goji-related liver toxicity, which means there is no body of evidence behind it yet and no way to say how likely it is.

this case is the first publication that goji berries can be toxic to the liver. Although larger studies are required, it should be kept in mind that liver toxicity may occur during intensive use.

In a study of people already allergic to plant foods, four of 30 recruited patients reported symptoms after eating goji berries, and the authors concluded goji berries have allergenic potential in this high-risk group. (Source 3)

• Case series, Certainty not rated.
• Size: 30 plant food-allergic individuals recruited, plus the index patient.
• Who: People with existing plant food allergy attending an allergy clinic in Spain.
• How long: recruited over 3 months in 2010.
• Result: 4 reported symptoms on intake, 6 tolerated the berries and 20 had never tried them; skin tests to goji were positive in 24 patients (77%), and positivity tracked with sensitisation to the panallergen lipid transfer protein.
• Funding: not stated.

Limit of this finding: The paper's own numbers do not hold together, and two of them should not be carried forward. Its abstract says "Nearly half of the patients reported symptoms (45%)", but that percentage is calculated against only the 11 patients who had ever actually eaten a goji berry, not against the full series; measured against the series it is about 16%. Its abstract also says 89% of skin-test-positive patients had never eaten goji berries, which the paper's own body contradicts — the body gives 16 of 24, about 67%. The methods say four patients reported symptoms while the results say five, and the series totals 31 rather than 30 because an index patient is included without being counted. Take the concrete counts — 4 reported symptoms, 6 tolerated the berries, 20 had never tried them — and note these were people already allergic to plant foods, not the general population.

Four patients reported symptoms on intake, 6 tolerated the berries, and 20 had never tried Goji berries.

In January 2022 a company, BCS International Corp., announced a recall of a goji berry snack for undeclared sulfites and the FDA posted the notice; the sulfites were found by New York State inspectors, not by the FDA. (Source 4)

• Official position, Certainty not rated.
• Size: not applicable.
• Who: Consumers with sulfite sensitivity, particularly asthmatics.
• How long: not applicable.
• Result: New York State Department of Agriculture and Markets sampling and laboratory analysis found 13.6 mg of sulfites per serving with no sulfite declaration on the label, against a reported 10 mg per serving level said to elicit severe reactions in some asthmatics; the notice records that no illnesses or allergic reactions involving the product had been reported.
• Funding: not applicable.

Limit of this finding: This is a company's own recall announcement that the FDA published, not an FDA finding: the testing was done by New York State Department of Agriculture and Markets inspectors and the FDA neither tested the product nor reached a conclusion about it. It concerns one mislabelled product in January 2022, not goji berries in general — sulfites are an added preservative, not something goji contains naturally — and the notice states no illnesses had been reported.

Consumers who have severe sensitivity to sulfites run the risk of serious or life-threatening allergic reactions if they consume this product.

What the evidence supports

In a randomized, double-blind, placebo-controlled trial of a standardized goji juice, the goji group's self-rated scores for energy, sleep, focus and mood improved significantly between day 1 and day 15; these are reported feelings, not measured changes in the body. (Source 5)

• Randomized trial, Low certainty.
• Size: 34 healthy adults (16 goji juice, 18 placebo)
• Who: Healthy adults.
• How long: 14 days.
• Result: Within-group increases from day 1 to day 15 in the goji group (N = 16) across energy, athletic performance, sleep quality, ease of awakening, focus, mental acuity, calmness, health, contentment and happiness; the placebo group (N = 18) showed only two significant changes (heartburn and happiness)
• Funding: industry (the first author is employed by FreeLife International, LLC, the maker of the GoChi juice tested)

Limit of this finding: Two things limit this trial. First, the first author is employed by FreeLife International, the company that makes the GoChi juice being tested. Second, every positive result is a self-rated questionnaire score, and the objectively measured items — body weight, body-mass index, blood pressure, pulse rate and visual acuity — showed nothing at all. The significant changes are also within the goji group between day 1 and day 15, not a direct statistical comparison against placebo. With 34 people over 14 days, this is a small, short, industry-authored study of how people said they felt.

Significant differences between day 1 and day 15 were found in the GoChi group (N = 16) in increased ratings for energy level, athletic performance, quality of sleep, ease of awakening, ability to focus on activities, mental acuity, calmness, and feelings of health, contentment, and happiness.

A small unmasked randomized pilot trial found macular pigment optical density rose significantly in the goji berry group over 90 days, while it did not change in the lutein/zeaxanthin supplement group. (Source 6)

• Randomized trial, Low certainty.
• Size: 27 participants.
• Who: Healthy adults aged 45 to 65.
• How long: 90 days, dosing five times weekly.
• Result: MPOD significantly increased in the goji group at 0.25 and 1.75 retinal eccentricities (p = 0.029 and p = 0.044); skin carotenoids increased at day 45 (p = 0.025) and day 90 (p = 0.006); no changes in the lutein/zeaxanthin group.
• Funding: not stated.

Limit of this finding: This was a small pilot trial, it was unmasked, and it had no placebo arm — both groups got an active product, and everyone knew which. Results are reported as changes within each group over time rather than as a head-to-head comparison, so it does not establish that goji berries beat the supplement. Macular pigment density is a marker associated with macular degeneration risk, not eyesight or disease itself.

After 90 days, MPOD was significantly increased in the goji berry group at 0.25 and 1.75 retinal eccentricities (p = 0.029 and p = 0.044, respectively), while no changes were noted in the LZ group.

What the evidence does not support

The same trial found no significant change in musculoskeletal or cardiovascular complaints in either group, and no differences at all in its objectively measured outcomes. (Source 5)

• Randomized trial, Low certainty.
• Size: 34 healthy adults.
• Who: Healthy adults.
• How long: 14 days.
• Result: No significant changes in musculoskeletal or cardiovascular complaints in either group; body weight, body-mass index, blood pressure, pulse rate and visual acuity were not significantly different between groups or over time.
• Funding: industry (the first author is employed by FreeLife International, LLC, the maker of the GoChi juice tested)

Limit of this finding: Two things limit this trial. First, the first author is employed by FreeLife International, the company that makes the GoChi juice being tested. Second, every positive result is a self-rated questionnaire score, and the objectively measured items — body weight, body-mass index, blood pressure, pulse rate and visual acuity — showed nothing at all. The significant changes are also within the goji group between day 1 and day 15, not a direct statistical comparison against placebo. With 34 people over 14 days, this is a small, short, industry-authored study of how people said they felt.

All parametric data (body weight, etc.) were not significantly different between groups or between day 1 and day 15 for either group.

Where the research disagrees

How much of goji juice's apparent benefit to general well-being reflects a real effect, given that the positive outcomes were all self-rated and the trial was industry-linked

• GoChi trial authors (one manufacturer-affiliated), rct: These results clearly indicate that daily consumption of GoChi for 14 days increases subjective feelings of general well-being, and improves neurologic/psychologic performance and gastrointestinal functions. (Source 5)
• The same trial's objectively measured outcomes, rct: All parametric data (body weight, etc.) were not significantly different between groups or between day 1 and day 15 for either group. (Source 5)

How much

• Reference intake: No RDA or AI has been established for goji berries as an essential nutrient by NIH ODS, EFSA or the literature we reviewed. A 2025 review describes L. barbarum berries as “generally regarded as non-toxic” in traditional use while noting that research into possible toxic compounds in the fruit remains limited. (Source 7)
• Upper limit: No formal Tolerable Upper Intake Level has been set. Case reports flag risk in specific contexts rather than at a defined dose: a warfarin interaction occurred after a single 20 mL dose of goji wine, and its authors suggest caution above 6 to 12 g of the dried herb in patients on warfarin. (Source 1)
• Studied: A randomized trial gave 120 mL/day of a standardized Lycium barbarum juice for 14 days. (Source 5)
• Studied: A randomized pilot trial gave 28 g of dried goji berries, five times weekly, for 90 days. (Source 6)
• Studied: A case report describes harm after a single 20 mL dose of Gouqizi (goji) wine added to long-term warfarin therapy. (Source 1)

A common belief, and what the research shows

The belief: Goji berries are a completely safe superfood with no meaningful risks or drug interactions.

What the research shows: A case report describes a warfarin patient who developed hematuria with “an abnormal urinary red blood cell count of 33201.5/μl (the normal range is 0–23/μl)” after a single dose of goji wine, its authors concluding that “large doses (more than 6–12 g) of Gouqizi can significantly enhance the anticoagulant action of warfarin.” A separate case report states “this case is the first publication that goji berries can be toxic to the liver.” And an allergy study concluded: “Our results demonstrate the allergenic potential of Goji berries in high-risk individuals, which is probably due to cross-reactivity with LTP from other foods.” Each of these is a single report or a selected high-risk group, not a population risk.

Questions and answers

What is it?

Goji berries, also called wolfberries or Gouqizi, are the fruit of Lycium barbarum, a deciduous thorny shrub in the nightshade family, alongside potatoes, tomatoes and peppers. A 2025 review reports it accounts for nearly 90% of the goji berries on the market. The berries are usually eaten dried, or made into juice, tea or wine. (Source 8)

What does it do in the body?

Goji is marketed for general well-being, antioxidant status and eye health. Small trials have reported improvements in self-rated energy and mood, and a rise in a marker of macular pigment density, but the trials are small, short and in one case industry-linked. The authors of the largest well-being trial say more research is needed before the effects can be considered established. (Source 5)

Is it good or bad for you?

A 2025 review describes goji berries as generally regarded as non-toxic in traditional dietary use, while noting that, as a nightshade, questions about tropane alkaloids in the fruit have not been well studied. Against that, specific documented harms exist: a case report of a serious warfarin interaction, a case report of liver toxicity, and allergic reactions in people already allergic to plant foods. Whether it is good or bad depends heavily on the person and the context. (Source 7)

How do you get more of it?

Goji comes from the Lycium barbarum plant, eaten as dried berries or drunk as juice, tea or wine. As studied, one randomized pilot trial gave 28 g of dried goji berries five times weekly for 90 days; another randomized trial gave 120 mL of a standardized goji juice daily for 14 days. (Source 6)

If it is harmful, what reduces it?

Not answered in the sources we could verify. The case reports describe the harms and call for caution and further study, but none of the passages we could read verbatim describes what reverses a goji-related problem once it starts, beyond the implicit step of stopping the product. (Source 1)

We searched: Searched the Gouqizi-warfarin case report and the goji hepatotoxicity case report for a verbatim statement describing recovery or reversal after goji was stopped; the reachable text of both gives presentation, findings and conclusions but no such recovery statement.

Why might someone be low in it or missing it?

Not directly addressed in the literature we reviewed. Goji is a food and traditional remedy rather than a nutrient the body requires, so the sources we found do not describe a goji-deficient state. (Source 8)

We searched: Searched for 'goji deficiency' and 'Lycium barbarum essential nutrient'; found no such literature, only reviews of its botany, food uses and health claims.

Which whole foods contain it or feed it?

The whole-food source is the goji berry itself, the fruit of Lycium barbarum. A 2025 review notes it is usually eaten dried or blended into other foods such as yogurt, tea and granola. Other parts of Lycium plants, including leaves, young shoots and root bark, have also been used traditionally. (Source 9)

What happens if you do not have it?

Not directly addressed. Because goji is not an essential nutrient, the literature we reviewed describes no consequence of not eating it. (Source 8)

We searched: Searched the 2025 review and the goji trials located for any described consequence of not consuming goji berries; none describes one.

How can you test for it?

There is no validated test of goji intake itself. The clinically relevant test is INR monitoring for people taking warfarin who also take goji or Gouqizi products, since a case report describes a patient losing control of a previously stable INR range after drinking goji wine. (Source 1)

References

1. Toxicology Reports. Bleeding due to a probable interaction between warfarin and Gouqizi (Lycium Barbarum L.). 2015. PMID 28962463. Read the source
2. Journal of Emergency Medicine Case Reports. A New Hepatotoxic Agent: Goji Berry. 2019. DOI 10.33706/jemcr.517021. Read the source
3. Journal of Investigational Allergology and Clinical Immunology. Goji Berries (Lycium barbarum): Risk of Allergic Reactions in Individuals With Food Allergy. 2012. PMID 23101309. Read the source
4. U.S. Food and Drug Administration. BCS International Corp. Issues Alert on Undeclared Sulfites in “Dr. Snack Goji Berry”. 2022. Read the source
5. The Journal of Alternative and Complementary Medicine. A Randomized, Double-Blind, Placebo-Controlled, Clinical Study of the General Effects of a Standardized Lycium barbarum (Goji) Juice, GoChi. 2008. DOI 10.1089/acm.2008.0004. Read the source
6. Nutrients (MDPI). Goji Berry Intake Increases Macular Pigment Optical Density in Healthy Adults: A Randomized Pilot Trial. 2021. PMID 34959963, DOI 10.3390/nu13124409. Read the source
7. Exploration of Foods and Foodomics. From botany to bedside: a review of the health benefits of Lycium barbarum as a functional food (safety and toxicity). 2025. DOI 10.37349/eff.2025.101070. Read the source
8. Exploration of Foods and Foodomics. From botany to bedside: a review of the health benefits of Lycium barbarum as a functional food. 2025. DOI 10.37349/eff.2025.101070. Read the source
9. Exploration of Foods and Foodomics. From botany to bedside: a review of the health benefits of Lycium barbarum as a functional food (traditional and food uses). 2025. DOI 10.37349/eff.2025.101070. Read the source