Monday, February 25, 2008

Don't Believe the Hype

Superfruit juices

Can juice from 'super' fruits — goji, noni, mangosteen or açai — really cure cancer?
Online 08/07


In brief
  • So-called "superfruits" — goji, noni, mangosteen and açai — are rich sources of antioxidants, but some of the marketing hype exaggerates the benefits of their juices. There’s no good evidence that drinking them will cure diseases such as cancer or diabetes.
  • You can pay as much as $85 for a 1L bottle of one of these juices. On a serve-by-serve basis, many common fruits such as strawberries and apples, contain more antioxidants, and are cheaper.
  • CHOICE sets out the facts about our testing and responds to the industry's claims about our approach.


Forget about an apple — if you really want to keep the doctor away, you need to knock back a daily dose of juice from goji, mangosteen or some other even more exotic "superfruit". Or so say the distributors of these products. Most suggest having at least one 30mL serve a day.

Açai (pronounced ah-sigh-ee), goji, mangosteen and noni fruits have a long history of traditional use. But it’s only in relatively recent times that they’ve gained the "superfruit" tag, been actively marketed and entered the mainstream. You can even find packs of dried goji berries adorning the aisles in Woollies.

So why buy them? The marketing message that’s common to all superfruits is that they — and their derivative products — are packed full of antioxidants. But when CHOICE tested the antioxidant activity of nine juices, we found it wasn’t as high as the marketing hype had led us to expect.


Brands tested

We tested the following açai, goji, mangosteen and noni juices:

  • Nu Açai and Guarana, from RioLife
  • Absolute Red NingXia Wolfberry Purée
  • Himalayan Goji Juice from FreeLife
  • Medicines From Nature Goji Juice
  • Tree of Health Goji Juice Blend
  • Xango Whole Fruit Beverage
  • Xanberry
  • Tahitian Noni Juice
  • Tree of Health Noni Juice

The CHOICE verdict
  • Superfruit juices contain a range of nutrients, but marketing spin has vastly exaggerated their health benefits. Until there’s much better scientific evidence, it’s cheaper and wiser to get antioxidants from other fruit (and veg) sources. A wide variety of types and colours of fruit and veg can help protect against diseases such as cancer, heart disease and type 2 diabetes — in part due to phytochemicals such as antioxidants, but also due to other nutrients they contain, including fibre.

  • Look into the claims and you’ll find there’s very little evidence to back them up. Testimonials abound, but they’re purely anecdotal. Marketers occasionally cite long lists of lab studies as ‘proof’ of the health benefits claimed. While some of the results of these studies are promising, there are few clinical trials, and what happens in a test tube or animal may not occur in humans. CHOICE looked in more detail at the scientific evidence for each fruit and has summarised our findings in Juices compared.

  • Health and therapeutic claims for food are currently prohibited under the Australia New Zealand Food Standards Code. Several websites for superfruit products pay lip-service to this fact by posting a disclaimer such as “this product is not intended to diagnose, treat, cure or prevent any disease”. But the health claims that appear above the disclaimer tell a different story. It’s clear that the regulation isn’t being effectively enforced for these products.

Some Truth

Choice compared a number of these so-called super-juices and found that:

  • their health claims are exaggerated.
  • the products are overpriced.
  • most of the drinks are sold via a Network Marketing (or MLM) process.


superjuice.jpg

Certainly the drinks contain a range of nutrients, but you may be surprised at the (often touted) antioxidant content.

For example (Note: TAC means Total Antioxidant Capacity)

  • You’d need to drink almost five 30mL serves of Tahitian Noni Juice to match the TAC of a navel orange (2540).
  • Three 30mL serves of Xanberry Mangosteen Juice Plus would still fall short of matching the TAC of a cup of strawberries (5938), raspberries (6058) or cultivated blueberries (9019).
  • The TAC of the humble Red Delicious apple (5900) is roughly equivalent to ten 30mL serves of Himalayan Goji Juice.

What about the scientific evidence? Choice provides some examples of potential health benefits. However real clinical trials on humans are scarce.

The Bottom Line

Fruit contains a vast array of nutrients - and most of us are not consuming enough fruits or vegetables. However, no single fruit or food will ever be the solution for all of our ailments, and - if anything - a diverse diet is best.

These super-juices are pricey and come with a number of spurious and anecdotal health claims.

Be sensible and wise. It's both sad and astonishing to see people with a diet consisting of pie and chips believing that a bottle of super-juice will make them well.

Nutrients

Acai - Origin Amazon Rain Forest, the fruit is picked daily and freeze dried within 24 hours of harvest.

Mangosteen - Origin Thailand, harvested when seasonally ripe for maximum efficacy, The xanthone rich pericarp is separated from the pulp and seed. The pericarp undergoes a freeze dried process.

Goji - Origin Tibet, also known as Wolfberry, grows on extensive vines in the sheltered valleys of the Himalayas in Tibet. The round, red berries are very tender and must be shaken from the vine rather than picked in order to avoid spoiling. The fruit is preserved by slowly drying in the shade.



Acai Berry - a nutritious berry found in the Amazon Rainforest. Acai was recently featured on the “Oprah Winfrey Show” and “MSNBC News."

Acai is reported to be the No. 1 Superfood in the world. Acai has a higher ORAC value than any other berry on the planet. Acai contains more anthocyanins that any other food.

Anthocyanins have been shown to restore mental function, concentration, memory, mental clarity. They are also know for capillary health which in turn helps with oxygen uptake, sexual performance, and the reduction of macular degeneration (vision loss due to aging). Due to their ability to protect the brain form free radical damage anthocyanins are know to be one of the most valuable anti-aging anti-oxidants known.

The famous research regarding the "French Paradox" attributes anthocyanins as being the antioxidant that protects the French from heart disease. The French are known to consume large amounts of coffee, nicotine, sugar, white flour and cheese and yet they have almost no incidents of heart disease. The red wine grape, due to its anthocyanins is what is believed to be responsible for the low incidence of heart disease. While red wine has anthocyanins the acai berry has 30 times the anthocyanins levels of that of red wine.

Cancer, heart disease, diabetes are all know to be "aging" diseases. Supplying yourself with quality "anti-aging" anti-oxidants along with a healthly diet is your first and best line of prevention.


Goji Berry - is grown in the Himalayan region of Tibet. The goji fruit has a long history of medicinal use that dates back thousands of years.

It has been used in general as an energy, restorative and longevity tonic. It also helps with a wide range of ailments from skin rashes and eyesight problems to diabetes.

The goji fruit is a very rich source of vitamins and minerals, especially in vitamins C, E, flavanoids, beta carotene and other bio-active compounds. It is also a fairly good source of essential fatty acids, which is fairly unusual for a fruit.

Goji is being investigated as a food that is capable of reducing the incidence of cancer and also as a means of halting or reversing the growth of cancers.


Mangosteen Pericarp - a delicious fruit grown in South East Asia. The mangosteen pericarp, which is the rind or peel, contains the highest level of xanthones known to man.

Laboratory tests have indicated that the xanthones in mangosteen pericarp have activity against several cancer cell lines including breast, liver, and leukemia.

Xanthones also contains anti-histamine and anti-inflammatory properties, as well as helping to assist with healthy blood sugar levels.

Pictures

Açaí Goji ("wolfberry")

Acai vs. Goji (Wolfberry)

Oxygen radical absorbance capacity -- "ORAC" -- is the most commonly used

quantitative measure of antioxidant strength in foods.

It has its problems, however. ORAC may vary unpredictably due to

variations in the plant species, growing conditions, environment,

harvesting and processing methods, assay conditions, oxidant species and

others..

Here are comparative data for antioxidant strength

Açaí (a)

Goji
“Wolfberry”
(b)

per 100 g
Euterpe
oleracea

Lycium

barbarum

Total phenolics*, mg
1,390
1,309^?

Main phenolic,

Proanthocyanidins, mg

1,289
nm

Ellagic acid, mg ^

nm
86 ?
Total carotenoids, mg
nm
182
Total ORAC
102,700
30,300^
Water-soluble ORAC
99,700
30,300
Fat-soluble ORAC
3,000
?

Brunswick Labs,

Total ORAC (c)

53,600

22,000


  • açaí may be best for water-soluble antioxidant applications (beverages)
  • goji may be best for mixed- or fat-soluble antioxidant applications

(foods, yogurt, smoothies)

  • açaí is difficult to transport as a whole fruit because of its high fat content

(series essay #1) which may oxidize and so limit it to use as a freeze-dried powder

  • goji has more versatility as a raw material, e.g., below as a whole dried fruit

(not possible for açaí)



Let's give the nod to açaí for its exceptional total ORAC!

Who wins the overall comparison between açaí and goji

for nutrient-richness, antioxidant strength and versatility as a functional food?

GOJI!

A nutrient-dense food: Series Essays #1 and #2

An antioxidant-rich berry, containing both phenolics and carotenoids: Series Essay #3

Versatile as a whole dried berry, juice and pulp powder.