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The Truth About Antioxidants: An In Depth Look at Acai and Raspberries

Monday, July 18, 2011 7:17 AM

Antioxidants are a primary component to good health because they neutralize free radicals that damage tissue in the body. Recently, high-priced antioxidants have been one of the hottest media topics for both their health benefits and the marketing claims from select distributors of products said to be high in antioxidants such as the exotic fruits, acai, mangosteen, and maqui. In fact, antioxidants are found in just about all fruits and vegetables and getting a healthy variety of them doesn’t have to break the bank. I present a sensible approach to staying young and healthy with these ten key points gathered from my research review.

1.    Variety: Consume a Combination of Fruits, Veggies, and Supplements.
Your best bet is to eat a wide variety of fruits and vegetables, with strategic supplementation, to get a healthy level of antioxidants that fight cell degeneration. It’s critical to get your antioxidants from an assortment of sources because there are several different antioxidants including ascorbic acid—also known as vitamin C—that are found in varying quantities in the different organic compounds that we eat. Some foods do have particularly high levels of antioxidants and minerals and it’s reasonable to focus on adding these to the diet for health. A brief list of foods with a variety of antioxidants include garlic, berries, cherries, artichokes, most spices such as cinnamon and cloves, nuts such as almonds, chocolate, and green vegetables. Supplements such as vitamin C, vitamin E, CoQ10, alpha lipoic acid, and selenium also contain large quantities of antioxidants.

2.    Be Smart About Marketing Claims.

I looked at the research on two of the fruits said to be highest in antioxidants on the planet: acai and raspberries. One disturbing trend in acai research is that the majority of the studies have been financed with grants or donations from acai berry and juice suppliers, which may have resulted in a conflict of interest or incomplete results being reported. Additionally, some acai companies have made positive health claims about the wonderful benefits of the antioxidants in acai once ingested into the body that haven’t been supported by the research so far.
3.    What Happens to Antioxidants in the Body?
A second concern with acai research is that many of the studies that report high antioxidant content are testing these berries using methods that don’t necessarily mean that the body can absorb the antioxidant nutrients in a way that is effective at preventing disease. For example, the commonly used Oxygen Radical Absorbance Capacity, or ORAC scale, tests for antioxidant level, but it is one of the least effective methods of predicting the behavior of antioxidants once they enter the body. For example, one study found that acai had an extremely high ORAC rating, but does mention that further tests are needed to determine how effective acai is in vivo.

4.    Tell Me More About Problems with the ORAC Scale.
One research study conducted at UCLA that was funded by a grant from POM Wonderful, the pomegranate juice company, noted that the ORAC method is the antioxidant rating most widely used by food manufacturers, but that has it has significant internal variability. One problem with the ORAC method is that over a period of 60 minutes, the antioxidant measurements of specific berries can vary widely based on different temperature gradients of the plates holding testing samples.

5.    Did the UCLA Study Use the ORAC Scale? What Did it Find?

The UCLA study used four different tests (one of which was the ORAC test) to rate the antioxidant makeup of the juices studied and came up with a composite score for each. The 100 percent pomegranate juice rated highest (big surprise since the study appeared to be commissioned by POM Wonderful), followed by red wine, concord grape, blueberry, black cherry, acai, cranberry, orange and apple. The acai juice had about 50 percent of the antioxidant composite score as the pomegranate juice.

6.    Are there Studies that Test the Effect of Acai on Health or Disease?
A 2011study funded by Sambazon, the first company to import acai from Brazil, found acai to reduce total cholesterol, fasting glucose, and insulin levels in an overweight population. Researchers concluded acai and other fruits with high antioxidant content could be used to counter metabolic disease. A second study of the benefit of a diet that included acai in rats found that it lowered dietary-induced high cholesterol. Researchers suggest this is because of acai’s high fiber and antioxidant makeup.

7.    Are there More Affordable High Antioxidant Fruits that are Just as Good as Acai?
Acai is only grown in the Amazon rainforest, meaning it is a bit pricey to consume in large quantities. Getting some acai in your diet is not a bad thing, but take note that there are many high antioxidant foods available for a more affordable price. Raspberries have a number of health benefits and they score well in tests for antioxidant content. A simple cost comparison shows that 100 capsules of one gram of red raspberry costs $14.80 from Amazon. A bottle of one gram capsules of acai costs $15.99 for 37 servings from Sambazon. Raspberries are less than half the cost of acai, and they can be easily found fresh and unprocessed at the grocery store—another benefit of many easily sourced high antioxidant foods including blueberries, cherries, and blackberries, radishes, grapes, spinach, carrots, artichokes, beans, red wine, and nuts.

8.    Are there Studies that Test the Effect of Raspberries on Health or Disease?
Yes! Raspberries can do some great things for the body. They contain a wide range of antioxidant compounds and other elements that play a significant role in decreasing cell damage from oxidative stress. One study found that a red raspberry extract was effective in killing 90 percent of stomach and colon cancer cells, of which antioxidants contributed to about half of the overall decrease in cancer cells. Researchers caution that the antioxidants in the raspberries played a “minor” role. Rather, they suggest that the raspberry extract enhanced the immune attack on the cancer cells in a similar way that resveratrol kills cancer cells. Black raspberries have been shown to kill esophageal cancer cells. Another study found that a raspberry, black grape, and red currant juice blend significantly decreased oxidative stress in cyclists.

9.    But How Do Raspberries Compare to Acai in Terms of Antioxidants?
In analyzing the antioxidant content of red raspberries, total antioxidant ratings for fresh berries are comparable to those of acai, but all antioxidants are not the same. Raspberries contain a large amount of a rare type of antioxidants called ellagitannins (raspberries are probably the most abundant source known), which are very uncommon in foodstuffs and have health benefits. It’s the ellagitannins that make raspberries such an excellent antioxidant choice because they have unique compounds that fight cancer, heal tissue and wounds, increase immune response, prevent cardiovascular disease, and help manage hyperglycemia, high blood pressure, and type 2 diabetes. Acai is not known to contain ellagitannins—rather its antioxidants are primarily anthocyanins and flavonoids.

10.    What is the Best Source for Raspberries?
Fresh is best when it comes to all foods, another reason why raspberries and other antioxidant fruits can be easily added to your diet. Research shows that processing, particularly removing the skin, decreases the retention of raspberry antioxidant properties. When raspberries aren’t in season, try my Phyto Px or Primal Reds for a powerful antioxidant supplement that both include whole raspberry powder.

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