Irvingia Gabonensis (African Mango): Research and Safety

Irvingia gabonensis, sold as African mango, is a West and Central African tree whose seed kernel extract is marketed for weight management. A handful of small trials, mostly from one research group, reported lower body weight and waist size than placebo, but independent reviewers rate those trials as poorly reported and at high risk of bias. The honest summary: interesting, unproven, and not well studied for long-term safety.

Key Takeaways

African mango supplements are made from the seed kernel (the "dika nut"), not the fruit flesh you would eat.
Three early trials, all by the same Cameroon-based authors, reported weight and waist reductions versus placebo, with doses from 300 mg to 3,150 mg a day for 4 to 10 weeks.
Systematic reviews in 2013 and 2020 judged the trials too few, too small and too poorly reported to prove an effect; the only trial rated low risk of bias found no significant difference.
The largest trial was partly funded by the company that supplied the extract.
Reported side effects were mild (headache, sleep difficulty, gas), but human safety has not been rigorously studied and one case of serious kidney decline has been published.

Evidence grade: Emerging. About five small, short randomized trials in people, most rated at high risk of bias by independent reviewers, with mixed results in the one higher-quality trial.

What Is Irvingia Gabonensis?

Irvingia gabonensis is a fruit-bearing tree native to western and central Africa [1]. It is also called African mango, bush mango, wild mango or dika nut [6]. Despite the name, it is a different plant from the common mango (Mangifera indica) sold in grocery stores. We explain the botany and nutrition differences in the difference between African mango and regular mango.

Different parts of the tree have different uses. The ripe fruit pulp is eaten fresh or made into juice, and a 2024 review describes the pulp as rich in vitamin C [6]. The kernels inside the seed are widely traded and used in traditional West African cooking [6]. Mucilage from the seed is used to make traditional soups and sauces [7].

Seed extract versus fruit

Supplement interest centers on the seed kernel. The kernel is mostly oil, made up largely of myristic and lauric acids. Once the oil is removed, the remaining extract contains flavonoid glycosides and ellagic acid derivatives [6]. Supplements use either ground seed or a concentrated extract. The most studied extract is a proprietary product called IGOB131 [1][3].

This distinction matters. Eating the fruit is not the same as taking the seed extract, and none of the weight-related trials tested the fruit.

Why Researchers Became Interested

The NIH Office of Dietary Supplements (ODS) summarizes the proposed mechanisms. In laboratory cell studies, the seed kernel extract inhibited adipogenesis, the process by which new fat cells form. In one human trial, the IGOB131 extract lowered blood levels of leptin, a hormone that tracks with body fat [1][3]. The earliest trial was framed around the seed as a source of dietary fiber [2].

These are proposed mechanisms. Results in cells do not show that the same thing happens in a person taking a capsule.

What the Human Trials Measured

Only a few randomized controlled trials have tested Irvingia gabonensis in people. The table summarizes the main ones we could verify.

Trial	Who took part	Product and daily dose	Length	What was reported
Ngondi et al., 2005 [2]	40 adults in Cameroon (28 active, 12 placebo)	Seed preparation, 1.05 g three times a day (3.15 g/day)	1 month	Body weight fell 5.26% vs 1.32% on placebo; changes in blood lipids also reported
Oben et al., 2008 [8]	72 adults in Cameroon, three groups of 24	Cissus quadrangularis alone, or combined with Irvingia, twice daily	10 weeks	Both active groups beat placebo; the combination did better, but Irvingia was never tested alone
Ngondi et al., 2009 [3]	102 adults with a BMI above 25 completed (120 enrolled)	IGOB131, 150 mg before lunch and dinner (300 mg/day)	10 weeks	Average weight change of -12.8 kg vs -0.7 kg on placebo; lower waist, body fat, cholesterol and glucose reported
Méndez-Del Villar et al., 2018 [9]	24 adults in Mexico meeting metabolic syndrome criteria (12 per group)	150 mg twice daily (300 mg/day)	90 days	Waist fell from 94.0 to 91.0 cm; lower triglycerides and later-hour glucose during a glucose test
Nonsa-Ard et al., 2022 [10]	Adults with overweight in Thailand	300 mg once daily	12 weeks	No between-group differences in metabolism or inflammation; higher plasma vitamin C and adiponectin

The 2005 seed trial

In the first trial, 40 adults followed a calorie-appropriate diet and took either ground seed or placebo three times a day for one month [2]. The seed group lost an average of 5.26% of body weight, against 1.32% in the placebo group. The groups were unequal in size (28 versus 12), and the trial lasted only four weeks.

The 2009 IGOB131 trial

This is the trial most often quoted on supplement labels. The reported difference was very large: an average loss of 12.8 kg on the extract against 0.7 kg on placebo over 10 weeks [3]. Several details deserve attention when you read it:

Part of the funding came from the company that prepared the extract and supplied the capsules [3].
The published full text contains numbers that do not fully agree with each other. For example, the waist-change figure in the table does not match the start and end values listed, and the group sizes after dropouts do not line up with the dropout counts given [3].
Eighteen of 120 people dropped out, including 10 who left because they did not lose weight quickly [3].

Later trials

A 2018 trial in Mexico used the same 300 mg daily dose for 90 days in 24 adults. It reported a three-centimeter drop in average waist size and lower triglycerides [9]. A 2022 trial in Thailand, funded by a supplement company, gave 300 mg a day for 12 weeks. It found no differences from placebo in metabolism, inflammation or aerobic capacity. The extract group did show higher plasma vitamin C and adiponectin [10].

What Independent Reviews Concluded

The trials look positive on paper, but reviewers who did not run them have been cautious.

2013 systematic review. Researchers at the University of Exeter found three randomized trials. All had flaws in how their methods were reported. They concluded that the effect on body weight is unproven and that Irvingia gabonensis "cannot be recommended as a weight loss aid" [4].
NIH ODS. The ODS fact sheet notes that the trials in that review used different methods, small samples, short durations and doses ranging from 300 mg to 3,150 mg a day. It adds that all of them were conducted by the same authors [1].
2020 meta-analysis. A review of five randomized trials rated four as high risk of bias. Pooled results favored the extract, but the one trial rated low risk of bias showed no significant difference in weight outcomes [5].
2020 review of herbal products for weight loss. A larger review covering 54 trials of many herbs listed Irvingia among products tested in three or fewer trials. It warned that these findings should be read cautiously because of poor methods and reporting. It concluded there was not enough evidence to recommend any of the herbs it reviewed for weight loss [11].

Retraction status. As of October 2026, we found no retraction notice or expression of concern attached to these trials in PubMed or on the journal pages. The concerns above come from published reviews and from the trial reports themselves, not from formal retractions.

Doses Used in Studies

There is no established dose for Irvingia gabonensis. The studies used two very different approaches [1][2][3]:

Standardized extract (IGOB131 or similar): 300 mg a day, usually split as 150 mg taken 30 to 60 minutes before lunch and dinner, for 10 to 12 weeks.
Ground seed: 3.15 g a day, split into three doses, for one month.

Products on the market vary in what part of the seed they contain and how concentrated it is. A study dose of one product does not carry over to another. If you are weighing this supplement, the habits with the strongest evidence still come first: an eating pattern you can keep, regular activity and sleep. Our guide to the Mediterranean diet for weight management covers one well-studied approach.

Safety and Interactions

NIH ODS describes Irvingia gabonensis extract as appearing well tolerated, but notes that its safety has not been rigorously studied in humans [1].

Reported side effects. Trials reported headache, difficulty sleeping, flatulence and gas. These were generally mild [1][4]. Trials lasted only one to three months, so longer-term effects are unknown. See African mango side effects for more detail.
Animal toxicity data. A 90-day rat study found no adverse effects at up to 2,500 mg per kilogram of body weight a day [7]. The lead author worked for the company that supplied the extract, and rat data cannot set a safe human dose.
Kidney case report. A 2015 report described a 42-year-old with existing kidney disease whose kidney function declined rapidly, leading to dialysis, after 2.5 months of African mango use [12]. A single case cannot prove cause, but anyone with reduced kidney function should talk to their doctor first.
Medications. Trials reported changes in blood glucose and blood lipids [2][3][9]. If you take medicine for blood sugar, such as insulin or metformin, or medicine for cholesterol, talk to your doctor or pharmacist before using African mango. No formal drug-interaction studies were found.
Pregnancy, breastfeeding and children. Safety in these groups has not been studied, and human safety in general has not been rigorously evaluated [1]. Avoid it unless your clinician advises otherwise.

Frequently Asked Questions

Is African mango the same as regular mango?

No. African mango is Irvingia gabonensis, a different tree from the common mango (Mangifera indica). Its fruit is eaten locally, but supplements are made from the seed kernel, often called the dika nut [1][6].

Does Irvingia gabonensis help with weight loss?

Small trials reported weight and waist reductions versus placebo, but independent reviews found them poorly reported and at high risk of bias. The only trial rated low risk of bias found no significant difference. Its effect on body weight is not established [4][5].

How much African mango was used in studies?

Extract trials used 300 mg a day, usually 150 mg before lunch and dinner, for 10 to 12 weeks. An earlier ground-seed trial used 3.15 g a day for one month. There is no established dose [1][2][3].

Can eating the fruit give the same results?

No study has tested that. The research used seed preparations, not the fruit pulp. The pulp is a food that supplies vitamin C and carbohydrates [6].

What are the side effects of Irvingia gabonensis?

Trials reported mostly mild headache, sleep difficulty, flatulence and gas. One case of rapid kidney decline has been published in a person with existing kidney disease. Talk to your healthcare provider before use [1][12].

Were the African mango studies retracted?

We found no retraction notice for the main trials as of October 2026. They have been criticized by independent reviewers for small size, poor reporting, high risk of bias and coming from a single research group, and the largest trial was partly funded by the extract supplier [1][3][4][5].

Sources

Disclosure: OPA Nutrition sells supplements, including products mentioned in this article. This content is for education only and is not medical advice. Statements about dietary supplements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. Talk to your healthcare provider before using any supplement, especially if you take medication or have a medical condition.

Written and reviewed by Michael Gonzales, Founder, OPA Nutrition · Last reviewed: October 17, 2026 · How OPA researches and writes

Irvingia Gabonensis (African Mango): Seed Extract, Studies and Safety

Key Takeaways