Blueberries for Cholesterol

A diet rich in blueberries may help reduce cholesterol levels, a new study suggests.

High cholesterol, or hypercholesterolemia, is a condition in which there are unhealthy levels of cholesterol in the blood. It is also called dyslipidemia, hyperlipidemia and lipid disorder.

Too much cholesterol in the blood is a major risk factor for heart disease. When cholesterol builds up in the arteries, this may cause the artery walls to stiffen – a condition called atherosclerosis. Atherosclerosis can cause angina or chest pain. If the cholesterol buildup restricts the blood flow to the heart, this may cause a heart attack.

If the arteries that supply blood to the brain become clogged, this may lead to a stroke. Both heart attacks and strokes are serious and potentially life-threatening conditions.

In the United States, about 20 percent of adults over the age of 20 have high cholesterol. Contrary to popular belief, more woman are affected by high cholesterol than men, particularly women between the ages of 65 and 74. According to the American Heart Association, 17.2 million men and 19.9 million women have dangerously high cholesterol.

The World Health Organization (WHO) reports that high cholesterol contributes to 56 percent of cases of coronary heart disease worldwide and causes about 4.4 million deaths each year.

Researchers from Atlantic Food and Horticulture Research Center, Kentville, Nova Scotia, Canada, conducted two feeding trials with pigs to determine the effects of blueberry supplementation on blood lipid levels and other indicators of heart health.

Blueberries have a diverse range of micronutrients, with notably high levels of the essential dietary mineral manganese, vitamin B6, vitamin C, vitamin K and dietary fiber. Especially in wild species, blueberries are rich in antioxidants.

In the first trial, basal diets contained a high level of plant-based components (70 percent soya, oats and barley). The trial found that supplementation with one, two and four percent blueberries resulted in a decrease in total, LDL (“bad”) and HDL (“good”) cholesterol. The greatest reduction was observed in the two percent blueberry-fed pigs, where total, LDL and HDL cholesterol were reduced 11.7, 15.1 and 8.3 percent, respectively.

In the second trial, basal diets contained only 20 percent of soya, oats and barley. The researchers found that the lipid-modulating effect of blueberries was weakened. Additionally, the supplementation with 1.5 percent blueberries reduced total cholesterol by eight percent only in pigs whose diets had been supplemented with cholesterol, sodium chloride and fructose.

The authors concluded that the cholesterol-lowering effects of the berries may be attributed to flavonoids, which act as antioxidants to protect against vascular insult and reduce vascular inflammation related to atherosclerosis.

Comments

[Ray]

Ahhh... blueberries, the super-fruit of summer. This is an interesting topic to me because it is surrounded by so much theory and speculation that has yet to be corroborated by clinical trials. (Does anyone know of any published trials?) It has been proposed that the body needs antioxidants (ex: folate that comes from fruits and vegetables) to combat homocysteine and its positively charged oxygen. If the O+ does not find an antioxidant, LDL cholesterol increases, which is thought to lead to build up of plaque in the arteries. Thus, blueberries may work to reduce cholesterol through their antioxidant effects, whereby homocysteine is reduced, and thus cholesterol is reduced. Interestingly, I have not been able to find any direct link between increasing antioxidants (fruits, veggies, folate, vitamin B12 etc.) and reductions in risk for cardiovascular diseases. However, several randomized, placebo-controlled trials are presently being conducted. What is more interesting is the percentage of women to men who have high cholesterol. I thought it was another statistic that men were more at risk for heart disease than women? If so, I find it difficult to see the causation between high cholesterol and cardiovascular disease. No doubt there is a correlation in increased risk...

[Shoshanna]

I suppose it just never hurts to eat a lot of blueberries, especially right now when they are in high season and delicious. It’s interesting that the cholesterol-lowering effect was more pronounced with a higher percentage of plant foods in the pigs’ feed. The authors don’t speculate on why this difference was observed, but maybe something in the blueberries works better in concert with plant-based compounds.

[DT]

How many blueberries do you need to eat to reduce the level of bad cholesterol? “The trial found that supplementation with one, two and four percent blueberries resulted in a decrease in total, LDL (‘bad’) and HDL (‘good’) cholesterol. The greatest reduction was observed in the two percent blueberry-fed pigs, where total, LDL and HDL cholesterol were reduced 11.7, 15.1, and 8.3 percent, respectively.” Is the decreased level of HDL bad? For patients with high cholesterol, the goal is to reduce LDL. Exercise and eating lots of vegetable are the best way to decrease cholesterol.

[molly]

Blueberries can not only lower cholesterol, but also stop liver cancer growth. This is an article I found for those who are interested http://www.nutraingredients-usa.com/news/ng.asp?id=67978-blueberries-anthocyanins-cancer

[Bella]

Blueberries have been all the rave the last six months. In addition to possible cholesterol-lowering effects, they may also be beneficial for colon cancer, memory and obesity. At least, for once, this super-food is actually tasty (and even in season). Just one more reason to go blueberry picking this weekend.

[ATAD]

Did you know that the fat-fighting compound in blueberries, pterostilbene, has been noted to have both cancer- and DM- fighting properties? I also learned that blueberries exhibit similar properties to resveratrol, which is found in grapes and is the reason why red wine in moderation is heart healthy. Apparently, there have been some reports stating that resveratrol found in blueberries is even more potent that the resveratrol found in red wines!

[SJ]

Have there been any studies to determine the difference in efficacy of using fresh, frozen, or canned blueberries? Also, are there any traceable results suggesting that organic, non-organic, and genetically modified fruit have different effects?

[troioitroi]

I personally think all the berries are good for you, especially due to their antioxidant effects. Furthermore, because of this cholesterol-lowering effect, blueberry is also thought to prevent colon cancer, the second-leading cause of cancer death in the US. Colon cancer is long thought to be linked to diets high in saturated fats and calories. Thus, by reducing these fats and cholesterol in the body, the colon will be protected.

[Ann]

Not only blueberries are good for high cholesterol, but they are also good for the skin. The antioxidant compounds helps to neutralizing damaging free radicals in the skin from excessive UV exposure.

[ley]

I thought that it was interesting to note that during WWII some British Royal Air Force pilots actually consumed bilberries, a relative of blueberries, to improve their night vision. Apparently, it was later reported that blueberries are high in bioflavonoids, which is what the rods in the eye use for night vision. So if you are ever driving late, you may want to consider eating some blueberries!!

[bilal]

Not surprising. The compounds that provide blueberries’ characteristic color are potent antioxidants that have many positive effects. As I’ve mentioned on this blog before, there are several books written about the benefits of consuming a colorful diet. Blueberries have the added benefit of being a healthful snack. They also contain a lot of water and fiber, which means you can eat a lot of them without consuming a lot of calories. Barbara Rolls at Penn State wrote a diet book called “Volumetrics” about the principle of consuming a diet that was high in fluid and fiber. People lost more weight when they ate foods like berries, soups and salads! Check it out: http://www.amazon.com/Volumetrics-Eating-Plan-Techniques-Calories/dp/0060737301/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1217021250&sr=8-1

[Joan Anderson]

It's nice to know that something good tasting is also good for our health. Does anyone know how the percentages translate into ounces of blueberries? Also, how often should blueberries be eaten to achieve ideal benefits, i.e., twice a week, more often, less often? Do the blueberries sold in grocery stores come from wild species, or are they "bred" for certain consumer-appealing characteristics with the possibility that the beneficial characteristics become lessened? In the winter, is it best to substitute frozen blueberries, and if so, are the benefits reduced? I believe one should eat everything in moderation, but how much would be too much when it comes to blueberries? Just curious, is there a point at which too much of any of the blueberries' properties might accumulate in one's system and be unhealthy?

[Annaliese]

Blueberries are also beneficial if your blood type is A. If you are familiar with the hypothesis of the book, "Eat for Your Blood Type," blueberries are particularly good for you. The concept says that chemical makeup of each blood type interacts differently with the chemical makeup of each ingested item. Thus, a food item that is healthy for you, might, in the case of another blood type, be unhealthy. After mostly following the A diet, I found myself to be experiencing less gastric discomfort. It is worth considering!

[Arthur]

Another virtue of blueberries is that they are not acidic! If you need to follow an alkaline diet due to GERDS or some other gastric problem, many fruits are off limits. Apples, apricots, peaches, plums, even watermelon are fruits to be avoided. Since I experience reflux, I have had to remove so many foods from my diet. I am grateful that some really good food items remain healthy for me!

[AJ]

It was also noted by Rutger’s Blueberry Cranberry Research Center located In New Jersey that blueberries contain analogous compounds to cranberries, which have been shown through research to prevent the bacterium, E. coli, from attaching to the bladder wall, resulting in the prevention of UTIs!

[conheo]

I found an article talking about blueberries reversing the short-term memory loss in the elderly. It is very interesting how such a little fruit can do so many useful things. Here is the link if anyone is interested: http://www.naturalnews.com/023039.html

[flower]

I found one article that said blueberries fight against prostate cancer. “A cocktail of antioxidants and blueberry juice has been shown to be effective in the fight against prostate cancer.” The initial trials at the University of Sydney were done in a Petri dish, but the testing soon moved to rats. "Over 10 days, the rats had a reduction in their tumor size by 30 percent, which is really significant in scientific terms," said Ms Fox
http://www.abc.net.au/news/stories/2007/12/08/2113425.htm

[cosmetic surgery rancho cucamonga]

If the cholesterol buildup restricts the blood flow to the heart, this may cause a heart attack. This is very informative; thank you so much for bringing up this.

[Vivian Musico]

I was just wondering if one can overdose on blueberries. While blueberries are in season, I have been eating a very large amount of the fruit. Is there any danger in that? Also, when blueberries are out of season, do frozen blueberries have the same effect? Thank you