Nutrients in the berry
Bellow is a table which shows the typical amounts of each nutrients found in 100g of freeze dried acai berry. As with many fruits, there is usually a high water content, which freeze drying eliminates. This makes the powder form a much more concentrated (but processed) form of the berry.
As you can see from the table, the acai berry has a broad spectrum of beneficial nutrients.
Variation In Form & Nutrient Content
Acai extract products do not contain all the nutrients above. In these products one nutrient (usually polyphenols) is isolated and extracted to give a high dosage of these compounds (similar to green tea extract). This means that you will not get the broad spectrum of nutrients that acai berry actually contains, and seems to defeat the point of using this berry only to focus on one aspect of it. This isn't to say the polyphenols are not beneficial. Polyphenols act as antioxidants and can interact with cells in our body on a genetic levels, but very little is fully understood about these products, and research into the polyphenols in acai berry has not revealed any particular benefit.
This is something which is becoming more and more common in health food shops. These products will have a high water content, and so will not have the same amounts of nutrients per unit weight as in the table abouve, but you will be able to consume larger amounts (i.e. 250ml glass a day instead of capsules). If the juice is made from whole fruits (i.e is effectively mashed up berries with very little else added to them) they will be very nutritious. However, many juices are made from concentrate, which involves removing a large amount of the pulp and dehydrating the product until there is no water left, then, after transport, rehydrating into a drink. This level of processing can damage the micro-nutrients, and also removes a lot of the fibre etc. This makes the product much less nutritious.
Freeze Dried Powder
Freeze drying is chosen over dehydrating with heat as it does less damage to the nutrients, but still removes all the moisture. This leaves a concentrated powder, which contains all the nutrients in the table above. Looking specifically at vitamin C, which is a water soluble antioxidant, we can see that we would need about 20g of freeze dried product to almost reach our RDA (66mg). Most acai supplements are in 500mg capsules, which would mean that you would need to consume over 40 capsules a day to reach your RDA.
Having such a broad spectrum of nutrients makes acai berry a 'jack-of-all trades, but master of none'. It will be beneficial to supplement your diet with them if you feel you are lacking in a lot of nutrients, but it will be very hard to consume enough acai powder to have a significant impact on levels of any specific nutrient.
This form of acai is highly processed and provides very little of the nutrients actually found in the berry to you. The purpose of this drink is to provide an alternative flavour to conventional tea. You may have some of the polyphenols infuse with the water in a similar way to black tea, but the vitamins, amino acids etc will not be present.
The Health Claims Made About Acai Berries
Since the acai berry hit the market in 2004 there have been a large amount of health claims made about it, many of which have not sustained. The most common claim is that acai products can help you to lose weight, and the amount of weight it will help you lose varies drastically. It is also regularly marketed as a 'colon cleanse' or 'detox' product. The idea behind these claims being that acai products are able to revitalise/ energise your body and clean out all the toxins. When sold as a colon cleanse product it is usually sold in combination with green tea or another product. It is also often advertised as reducing the oxidative stress on your body, by fighting radicals, and the extent of this protection can often be exaggerated.
What The Scientists Say
After reviewing recent scientific research into acai products, it is clear that acai berries posses strong antioxidant properties both in vivo and in vitro, both in their natural form and freeze dried. The antioxidant capacity of foods is given an ORAC (Oxygen Radical Absorbance Capacity) score, and acai berries have a score of 47800. To put this value into perspective, 100g of frozen blue berry powder has an ORAC value of 36000. This shows that acai powder has a greater ability to protect the body against harmful radicals than blueberries.There is no evidence to suggest that acai berries posses any other health benefits such as aiding with weight loss or providing a 'colon cleanse'. These claims, and many more seem to be fabricated for marketing purposes as they have no scientific support.
The acai berry is a very nutrient dense fruit, which contains a broad spectrum of beneficial nutrients. Consuming acai berries in the various forms available will benefit the consumer to varying degrees as the amount of each nutrient will vary drastically. The only proven benefit of consuming acai berries is the strong antioxidant properties it contains. Claims that acai berries can promote weight loss or act as a colon cleanse are simply marketing ploys to increase sales.