What is African mango?
Despite the name, african mango has nothing to do with the common mango (scientific name: mangifera indica). The plant in question is known as Irvingia gabonensis and the fruits of the tree look like mangoes, hence the colloquial name.
The supplement you are actually consuming comes from the seeds. The seeds have traditionally been used as a soup thickening agent, with other uses merely being cosmetic or industrial (fatty acids from plants tend to be used in making products, due to their physical properties). A very uneventful and boring history.
What is African mango said to do?
Irvingia gabonensis is said to be a fat burning agent, mostly due to one in vitro (conducted in a petri dish outside of a living system) experiment showing that it inhibited the activity of a receptor known as PPARgamma (PPARγ). Theoretically, this should reduce the rate of fat cell growth, and thus cause an anti-obesity effect.
Throw in sensationalist marketing and an endorsement from Dr. Oz (the same guy who pumped both raspberry ketones and green coffee extract based on questionable and limited evidence) and now you have a social craze around its fat burning effects.
What does it actually do?
It likely does not do anything substantial to PPARγ, to be honest. The one study conducted used a high concentration of the basic seed extract and, when using high concentrations, most polyphenolic compounds can be forced to influence PPAR receptors. Fatty acids themselves are ligands (access keys) to these receptors, so some influence with high concentrations is honestly expected. PPARγ inhibition from irvingia gabonensis has not yet been detected in a living system.
The active and/or unique molecule is not known and as such cannot be tested to see if this activity remains at lower concentrations; this is assuming such a bioactive exists, as research on this seed is sparse.
Studies done in humans are too few and questionable in nature. The disclosure on their methodology is suspect, and of the three trials actually conducted, two of them were financed by the company producing the seed, and one of them was actually a combination of african mango and cissus quadrangularis.
To sum up, the legitimate research in human data sucks right now
What is african mango likely to do? Based on its soup thickening properties and the recommendation to take it 30 minutes before a meal rather than alongside the meal, it is likely that this supplement is relying on the gel forming (thickening) properties to occur in the stomach and suppress appetite. This is reliably seen, to a small magnitude of benefit, with isolated glucomannan supplementation (a gel forming soluble fiber). The dietary fiber composition of african mango is not yet characterized, but it appears to be soluble and gel forming in nature.
African mango may turn out to be an expensive way to get some fiber to suppress appetite, without any real fat burning effects.
Why should I use it?
At this moment in time, there is absolutely no reason to use african mango. No unique molecules have been isolated from the plant, and due to its marketing hype, it’s not a cheap supplement.
The properties observed with african mango very closely mimic that seen with glucomannan. Buying glucomannan is likely to be much cheaper and confer the same, if not more, benefits as you are getting a higher amount of glucomannan per gram (Irvingia gabonensis is about 3% fiber by weight).