Mangosteen: Great Taste, Inflated Claims
If you already know what a mangosteen is, it means one of two things: either you have spent your vacation in Thailand, where this delicious fruit is widely sold, or you keep track of the latest weight loss fads. In the West, mangosteen juice is promoted not just as a way to get slim, but as the next best cure for cancer. Can that possibly be true?
The proven benefits
One thing is certain: mangosteens are delicious! Purple on the outside, they conceal several segments of white, tender, sweet and fragrant flesh. And as all fruits, it contains many vitamins and nutrients – here are a few:
- Vitamin C – while it may not cure common cold, it has many other benefits, which we have written in one of our articles
- Vitamins of the B group – necessary for metabolism, immune system, and production of “good” cholesterol;
The xanthone mystery
It is not mangosteen’s vitamin contents, however that have attracted so much online attention. Rather, it is chemical compounds called xanthones – occuring in various tropical plants, they are particularly abundant in mangosteens. According to the producers of mangosteen puree and juices, xanthones can do many things for you:
- Fight cancer – alpha-mangostin (one of the xanthones) in particular is cited as potentially efficient against prostate cancer (see this study, for example), breast cancer, and skin cancer;
- Prevent allergy – some data show that mangosteen extract can inhibit the production of histamines, which cause allergic reactions;
- Keep blood sugar low – according to some researchers, mangosteen can inhibit the enzyme alpha-amylase, which is responsible for breaking down carbs.
Does it make you lose weight?
This claim is what made mangosteen juice all the rage. According to the manufacturers, this miraculous effect is due to its high level of fiber, which (presumably) absorbs sugar and fats that you eat. The effect is frequently supported by citations of research papers. There are two issues with mangosteen’s miraculous slimming powers, though.
- Beware of company-funded research. Unfortunately, it is common for manufacturers to order research to be conducted… with the sole purpose of “proving” their marketing claims. Such studies are usually done using small samples and are methodologically dubious (more critical info here).
- The sponge effect. On websites selling mangosteen juice, you will often read that its high level of fiber causes you to eat less and absorbs sugar and fats as a sponge. It is true that fiber is essential for good digestion, and it does partially prevent the absorbtion of fats. The issue is that there are many plant foods that contain much more soluble fiber than mangosteen does. The best are oats, barley, beans, and lentils, followed by pears, apples and other fruit.
As you can see, the problem is not that mangosteen doesn’t provide health benefits – it does, but so do all other fruits. The real problem is that marketing wizards try to make you pay a lot of money for benefits that you can easily get elsewhere. A bottle of mangosteen juice sells for up to 50 dollars – compare that to a pack of oats or apples… and make a wise choice.