Food

Super-juices

Updated: 02 Dec 2008
Super-juices-hero

Introduction

Are "super-juices" the antioxidant-packed miracle cures their promoters would have you believe, or just a waste of money?

Super-juices are the latest food fad and have brought out of obscurity fruits such as mangosteen, noni, acai and goji - all of which have a long history of traditional use. They've now been elevated to "super-food" status and become commercially available as juices.

We tested their antioxidant capacity and compared them to ordinary juices to find out whether the hype is justified.

What super-fruits do

Mangosteen fruit

All 4 super-fruits (mangosteen (pictured), noni, acai (pronounced ah-sigh-ee) and goji) are considered to be rich in antioxidants - these are beneficial chemicals (phytochemicals) in fruit, vegetables and other plant foods that neutralise the harmful "free radicals" our bodies produce.

Free radicals are made in the body during normal metabolism and during exposure to infection, UV light, pollution, radiation, and even exercise. Free radicals damage cells and speed up the ageing process.

Studies have shown an association between high intakes of antioxidants (especially from fruit and vegetables) and a lower risk of cancers and cardiovascular disease.

About our test

We tested 4 super-juice products for their antioxidant capacity:

  • XanGo (mangosteen)
  • Cook Islands Noni Juice
  • MonaVie (acai)
  • Himalayan Gold Super Goji Juice

Our super-juices were bought from health-food stores and through multi-level marketing networks. We also tested 5 ordinary supermarket juices to see how they compared.

Our lab used the industry-standard oxygen radical absorbance capacity (ORAC) test to determine the antioxidant capacity of the juices. ORAC measures the degree to which a substance neutralises free radicals and how long it takes to do so. These two measurements are then combined into a single unit or ORAC score per serving.

What we found

According to our test results, you get a much better antioxidant bang for your buck with fresh fruit and vegetables. We think you're just wasting your money on super-juices.

Exposing the hype

We compared the juices according to their usual serving quantity. A recommended serving for most of the super-juices is 30ml (40ml for Cook Islands Noni Juice) and a serving of supermarket juice is a standard glass: 250ml.

On a per-serve basis, a standard glass of any of the supermarket juices we tested had a higher antioxidant capacity than the recommended dose of any of the four super-juices.

On a 30ml serving, MonaVie had the highest tested antioxidant capacity of the super-juices tested: an ORAC score of 1146 per 30ml. But all the supermarket juices did much better than this on a 250ml basis. A 250ml glass of the blackcurrant and dark grape juices has around 5 times the antioxidant capacity of a MonaVie 30ml serving.

The other three super-juices had much lower ORAC scores: 30ml of these super-juices had an ORAC score similar to 30ml of the supermarket grape or blackcurrant juices.

Both XanGo and MonaVie contain citric acid - a preservative with antioxidant properties. It's added to extend the product's shelf life but it also contributes to its ORAC score.

Very expensive apples

The humble Granny Smith apple has an ORAC score of 5067 (per 130g apple). To get the antioxidant equivalent from a super-juice, you would have to down at least 4 30ml shots of MonaVie, 6 40ml shots of Cook Islands Noni Juice, nearly 7 30ml shots of XanGo, or more than 10 30ml shots of Himalayan Gold Super Goji Juice.

These juices aren't cheap. We paid between $28 and $81 per bottle (750ml or 1L). If you take the recommended daily "dose", a bottle will last about a month.

The most expensive product we tested was XanGo (mangosteen). At $81 for 750ml, it works out at $3.24 per 30ml serve. And it turns out that its antioxidant capacity isn't much higher than that of a same-sized serving of regular grape or blackcurrant juice.

One Granny Smith apple costs about 55 cents and has the same antioxidant capacity as nearly $23 of Xango. Forget the super-juice and eat an apple is our advice.

Test results

We compared the antioxidant capacity of the juices on a per-serve basis. See What we found for more information.

Table comparing super-juices

Guide to the table

Our test was carried out by an independent New Zealand laboratory.

  • Products are listed, within categories, in alphabetical order. A = concentrate diluted 1:7 as per label.
  • Price per serve is based on what we paid per bottle in September 2008.
  • ORAC score per serve for fruit and vegetables taken from US Department of Agriculture ORAC of selected foods 2007 database. ORAC = oxygen radical absorbance capacity, see About our test for more information.

Marketing hype

Juice on a tray

Marketing literature for many super-juices refer to the superior antioxidant capacity of the super-fruits they contain.

For example, a glossy MonaVie brochure claims that on a gram-for-gram basis the antioxidant capacity of the freeze-dried acai berries in MonaVie is more than 15 times higher than blueberries and more than 20 times higher than raspberries.

We think it's unfair to compare freeze-dried acai berries to fresh blueberries and raspberries. The freeze-dried acai contains no moisture so it's a much more concentrated source of antioxidants.

MonaVie contains 25 percent acai: the other 75 percent comprises various fruits and additives. But it's not always clear just how much of the super-fruit a product contains. XanGo lists mangosteen puree as its first ingredient but doesn't say how much - and it also contains nine other fruit juices.

Read carefully and you'll see that the claims and "scientific studies" usually refer to the super-fruit, not the juice product itself. And while some super-fruits have shown promising results in lab studies, what happens in a test tube or lab animal may not occur in the human body.

Some products emphasise the benefits of specific components of the fruit. Mangosteen sets itself apart from other super-fruits as being rich in "xanthones" (a type of antioxidant) and goji is reported to be a unique source of "polysaccharides" (a fancy name for complex carbohydrates). We've simply tested the juices to find out their antioxidant capacity.

The marketing literature is also filled with impressive testimonials. Users of acai juice claim it cures joint pain, lowers cholesterol and controls diabetes among other (even more miraculous) claims. The mangosteen fruit "battles degenerative diseases like cancer, heart disease, diabetes, arthritis, and all forms of brain malfunctions".

Testimonials are the views of one person, not a scientific study. They should be treated like any other unverifiable opinion and given little credence.

Multi-level marketing

Super-juices such as XanGo and MonaVie are sold through multi-level marketing networks. Anyone can become a distributor and earn profits by either building an active customer base (which then buys direct from the parent company) or by recruiting distributors who build a customer base. Distributors can also earn a profit by selling products purchased from the parent company at wholesale prices.

The XanGo and MonaVie websites promise amazing financial rewards and "generous compensation plans" for distributors, but you'll need to sell a lot of juice to make a living. Multi-level marketing schemes are an aggressive sales method - if these products are as amazing as they claim to be, they should be selling themselves.

Our advice

  • Super-juices are seriously overpriced fruit juices and - at their recommended doses - deliver no more of an antioxidant punch than a glass of ordinary fruit juice.

  • Get your antioxidants from fresh fruit and vegetables. They're much cheaper and you'll get lots of other nutrients and fibre too.

  • Berries, especially blueberries, are rich in antioxidants. But there are lots of relatively cheap, widely available fruit and vegetables (like apples) that are rich sources of antioxidants.

  • Be wary of signing up to a multi-level marketing scheme to sell super-juices - check the level of sales required to make a decent living.


More information


Report by Libby Manley