How Super Are Acai Berries?
According to some of the marketing ads on the internet, TV health shows, and elsewhere, acai berries are a super fruit that offer a variety of health benefits you would be foolish to pass up. Are the claims of help with weight loss, levels of endless energy, and superior antioxidant power really true?
Can we truly claim that acai berries are a super food? What do we know about these exotic black-purple berries from the Amazon region of Brazil?
Marketing types like to stretch, manipulate, and “customize” data and other information in the interest of making a sale. So what does the scientific research say about acai berries?
A recent article in the Journal of Toxicology and Environmental Health explored the amount of essential minerals found in freeze-dried acai pulp made from the berries gathered from various locations. The investigators discovered that the fruits were rich in magnesium, zinc, calcium, and iron, but that levels of manganese and copper were “surprisingly markedly higher than the traditional sources of these elements in the human diet.”
If this sounds like a good thing, that’s not necessarily true. For example, a 300 ml serving of acai pulp provides more than a sixfold (average, 14.6 mg) amount of manganese. The Adequate Intake for this mineral is 1.8 mg for females and 2.3 mg for males, with a maximum intake of 11 mg for adults and from 2 to 9 mg for children.
Too much manganese can be a health hazard, especially for vegetarians, people who have anemia, and children, because the mineral can interfere with the absorption of iron. This finding led the authors of the study to note that while acai may be a “good dietary supplement to resolve malnutrition problems,” more studies are needed to analyze its potential impact on health.
This research is in the infancy stage, but it may have implications for diseases that involve beta-amyloids, such as Alzheimer’s disease. Beta-amyloids are proteins found in the bloodstream and cerebrospinal fluids and which can be deposited into plaques found in the brain.
Scientists found that use of acai berry extract protected against beta-amyloid-associated loss of cell viability and oxidative stress (which fuels disease). This finding suggests acai berries may have an ability to inhibit the aggregation of beta-amyloids and thus help protect the brain.
Could acai berries help lower cholesterol? Research in lab animals suggests that it may have this effect.
In one recent study, rats were divided into four groups: (1) standard diet, (2) standard diet plus acai pulp, (3) a high-cholesterol diet, and (4) a high-cholesterol diet plus acai pulp. At the end of the study, rats in the group fed the high-cholesterol diet plus acai showed a significant decline in total cholesterol and bad cholesterol (low-density lipoprotein) and an increase in good cholesterol (high-density lipoprotein) and the amount of cholesterol excreted in feces when compared with the group fed a high-cholesterol diet.
But people are not lab animals, so can acai berries lower cholesterol in people? The results of one human study offer a clue, but not much.
Ads for acai berry juice often say the product can help with weight loss, but the proof is slim (pun intended). In fact, there are no scientific studies that show acai berry use results in weight reduction.
A study appearing in Nutrition Journal did involve 10 healthy overweight individuals who were given acai fruit pulp. That study, however, focused on the impact of the fruit on risk factors for metabolic disorders.
All the people in the study took 100 grams acai pulp twice a day for one month. The researchers were interested in levels of glucose, insulin, cholesterol, triglycerides, nitric oxide metabolites, and high sensitivity C-reactive protein.
Use of acai pulp resulted in reductions in fasting glucose, insulin, total cholesterol, low-density lipoprotein (LDL), and the ratio of total cholesterol to high-density lipoprotein levels. These findings suggest acai berries may lower levels of certain indicators of metabolic disease risk in overweight adults, and that further research is needed.
Acai berries are an excellent source of phytonutrients and antioxidants, as noted in the findings of an analysis published in the Journal of Agriculture and Food Chemistry. In that report the authors noted that their evaluation of freeze-dried acai fruit showed it had “the highest antioxidant activity of any food reported to date….[and that] this fruit would be an excellent food to study for potential disease prevention effects in the future.”
Acai berries appear to be a wise addition to an overall healthful diet, but it’s too soon to say they possess any super powers.
Read more about berries for brain health
Da Silva Santos V et a. Acai (Euterpe oleracea Mart): a tropical fruit with high levels of essential minerals—especially manganese—and its contribution as a source of natural mineral supplementation. Journal of Toxicology and Environmental Health 2014; 77(1-3): 80-89
De Souza MO et al. The hypocholesterolemic activity of acai (Euterpe oleracea Mart) is mediated by the enhanced expression of the ATP-binding cassette, subfamily G transporters 5 and 8 and low-density lipoprotein receptor genes in the rat. Nutrition Research 2012 Dec; 32(12): 976-84
Schauss A et al. Antioxidant capacity and other bioactivities of the freeze-dried Amazonian palm berry, Euterpe oleraceae mart. (acai). Journal of Agriculture and Food Chemistry 2007; 54(22): 8604-10
Udani JK et al. Effects of Acai (Euterpe oleracea Mart) berry preparation on metabolic parameters in a healthy overweight populations a pilot study. Nutrition Journal 2011 ay 12; 10:45
Wong DY et al. Acai (Euterpe oleraceae Mart) berry extract exerts neuroprotective effects against B-amyloid exposure in vitro. Neuroscience Letters 2013 Nov 27; 556:221-26
Photo: Flickr/Jo Brodie