- Can Herbal Teas Lower My Cholesterol?
- Protective Properties
- Green tea lowers cholesterol, but only a little
- How Coffee Raises Cholesterol
- The (Wrong) Choice of Decaf Coffee Can Raise Your Bad Cholesterol Level
- Drink more tea to lower cholesterol: VUMC study
- Green tea may lower heart disease risk
- What the evidence shows
- The bottom line
Can Herbal Teas Lower My Cholesterol?
Antioxidants help fight cell-damaging free radicals in the body. Foods rich in antioxidants include:
Traditional teas and some herbal teas contain antioxidants. Antioxidant strength depends on the type of tea and its processing method. Hibiscus has the highest recorded level of antioxidants out of all herbal teas. Teas with berries, orange peel, and peppermint tend to have similarly high levels of antioxidants.
Some research indicates that antioxidants found in tea may help lower cholesterol. A meta-analysis from the American Journal of Clinical Nutritionsuggests that green tea significantly reduces total cholesterol, including LDL or “bad” cholesterol, in the blood to 2.19 mg/dL. However, green tea didn’t affect HDL, or “good” cholesterol.
Herbal rooibos, or redbush tea, may help improve your lipid profile, or levels of cholesterol in the blood. In a study from the Journal of Ethnopharmacology, participants who drank six cups of fermented rooibos every day for six weeks showed a decrease in LDL of about 0.7 mmol/L and an increase in HDL of about 0.3 mmol/L.
Ginger tea is usually thought of as a stomach soother, but it may help with cholesterol as well. Ginger powder significantly lowered lipid levels compared to a placebo in a double-blind clinical study.
Based on animal studies, dandelion tea may also reduce cholesterol. Bitter melon tea may improve your cholesterol and reduce your risk for cholesterol-related conditions. It can also have a host of other positive health-related effects. Bitter melon has been shown to help with type 2 diabetes, hemorrhoids, and even certain cancers.
Another study shows that peppermint tea can lower cholesterol by helping your body produce bile. Bile contains cholesterol, so the production of bile can put your cholesterol to better use.
You won’t see the effects of herbal tea on your cholesterol right away. Many studies note that you must drink herbal teas for weeks before there is any improvement in cholesterol. Some studies claim that you’ll notice a drop in blood sugar in less than an hour, as with hibiscus and bitter melon tea. Other studies show that improvements might not occur for over two months.
Your personal health and metabolism can also affect how quickly herbal teas help to improve your cholesterol. Talk to your doctor about your overall physical health to see how tea might affect your cholesterol levels.
Tea is rich in polyphenols, which are believed to have antioxidant, anti-cancer, anti-bacterial, and anti-viral properties. Green tea has the polyphenol catechin. Black tea, which is fermented green tea, contains the pigment of polyphenols known as theaflavins that are produced during the fermentation process.
Each 375-mg capsule of the combined extract used in the study contained the amount of theaflavin and catechin equal to that in 35 cups of black tea or seven cups of green tea, respectively. The extract is marketed by Nashville, Tennessee-based nutraceutical company Nashai Biotech, Inc., which funded the study.
The trial included 240 men and women in China with moderately high cholesterol who were already following low-fat diets. Half the participants took the tea extract for 12 weeks and the other half took placebos. The study is published in the June 23 issue of Archives of Internal Medicine.
Maron, who is an associate professor of medicine at Nashville’s Vanderbilt University Medical Center, says he was surprised by the large reduction in LDL cholesterol levels in the tea-extract group.
“These findings obviously have to be confirmed in larger studies with longer follow-up,” he says. “But for centuries tea has been thought to have medicinal uses, and here is a study that shows an apparent therapeutic value.”
Green tea lowers cholesterol, but only a little
NEW YORK (Reuters Health) – Drinking green tea seems to cut “bad” cholesterol, according to a fresh look at the medical evidence.
A woman pours hot water to make green tea at a traditional tea house in Boseong, south of Seoul, in this September 23, 2007 file photo. REUTERS/Han Jae-Ho
The finding may help explain why green tea has been linked to a lower risk of heart disease, the leading killer worldwide, Xin-Xin Zheng and colleagues from Peking Union Medical College in Beijing report.
Because few people in the U.S. drink green tea, encouraging Americans to down more of the brew could have significant health benefits, the researchers write in the American Journal of Clinical Nutrition.
Still, one U.S. expert cautioned the drink shouldn’t be used as medicine for high cholesterol, as the effect found in the Chinese study was small.
The new report pools the results of 14 previous trials. In each of those studies, researchers randomly divided participants into two groups: one that drank green tea or took an extract for periods ranging from three weeks to three months, and one that got an inactive preparation.
On average, those who got green tea ended up with total cholesterol levels that were 7.2 milligrams per deciliter (mg/dL) lower than in the comparison group. Their LDL, or “bad,” cholesterol dropped 2.2 mg/dL — a decrease of slightly less than two percent.
There was no difference in HDL, or “good,” cholesterol between the two groups.
The cholesterol-lowering effects of green tea may be due to chemicals known as catechins, which decrease the absorption of cholesterol in the gut, according to the researcher.
However, the cholesterol reduction with green tea is pretty small, cautioned Nathan Wong, who runs the heart disease prevention program at the University of California, Irvine.
He told Reuters Health the drink “should not be recommended in place of well-proven cholesterol-lowering medicines for people with high cholesterol.”
Some researchers have raised concerns over possible side effects from heavy consumption of green tea or green tea extracts. For instance, there have been a few dozen reports of liver damage, and green tea may also interact with certain medications to reduce their effectiveness.
Still, Wong said smaller doses of the brew “could be a useful component of a heart-healthy diet,” with benefits that may go beyond its effect on cholesterol.
SOURCE: bit.ly/kPFJLS American Journal of Clinical Nutrition, online June 29, 2011.
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How Coffee Raises Cholesterol
Cafestol, a compound found in coffee, elevates cholesterol by hijacking a receptor in an intestinal pathway critical to its regulation, said researchers from Baylor College of Medicine in a report that appears in the July issue of the journal Molecular Endocrinology.
In fact, cafestol is the most potent dietary cholesterol-elevating agent known, said Dr. David Moore, professor of molecular and cellular biology at BCM, and Dr. Marie-Louise Ricketts, a postdoctoral student and first author of the report. Cafetiere, or French press coffee, boiled Scandinavian brew and espresso contain the highest levels of the compound, which is removed by paper filters used in most other brewing processes. Removing caffeine does not remove cafestol, however.
Studies by a co-author – Dr. Martijn B. Katan of Vriye Univeriteit Amsterdam, Institute for Health Sciences, The Netherlands – indicate that consuming five cups of French press coffee per day (30 milligrams of cafestol) for four weeks raises cholesterol in the blood 6 to 8 percent.
However, while the cholesterol increase associated with cafestol had been identified previously, mainly through the work of Katan and his colleagues, the mechanism by which it acted remained a mystery. It was a mystery that Moore and Ricketts decided to address in the laboratory.
For a long time, Ricketts said she was stymied because of paradoxical effects of cafestol in the liver. However, the discovery of a gene called fibroblast growth factor 15 or FGF 15 opened the door to understanding how cafestol affects farsenoid receptor X or FXR in the intestine. FXR was first identified as a bile acid receptor in studies in several laboratories, including Moore’s.
“It is part of the body’s own way of regulating levels of cholesterol,” said Ricketts.
Through research in the test tube and in mice, she and Moore found that in the intestine, cafestol activates FXR and induces FGF15, which reduces the effects of three liver genes that regulate cholesterol levels. While it is still unclear whether cafestol itself reaches the liver, the finding does confirm that the effect of the compound is in the intestine, which is directly involved in the transport of bile acids.
Moore’s interest in cafestol began several years ago when his wife read an article on coffee’s effect on cholesterol. She suggested that he might change his brewing method, which involved a permanent coffee filter. The paper filters, the article suggested, removed the coffee oils, which contain cafestol.
Moore researched the problem, and found papers by co-author Katan. He was already working on FXR, and began to think about whether cafestol might be affecting that signal in the cholesterol pathway.
Others who took part in the work include: Mark V. Boekschoten, Guido J.E.J. Hooiveld and Michael Müller of Wageningen University, Division of Human Nutrition, The Netherlands; Arja J. Kreeft, Corina J.A. Moen, Rune R. Frants of Center for Human and Clinical Genetics, LUMC, Leiden, The Netherlands; Soemini Kasanmoentalib of the Department of Medical Statistics, LUMC, Leiden, The Netherlands; Sabine M. Post and Hans MG Princen of TNO Pharma in Leiden, The Netherlands; J. Gordon Porter of Incyte Corporation, Palo Alto, CA.; and Marten H. Hofker of the Department of Pathology and Laboratory Medicine, University Medical Center in Groningen, The Netherlands.
Funding for this study came from the U.S. Department of Agriculture, National Institutes of Health, Wageningen Centre for Food Sciences, the Dutch Organization for Scientific Research and the Netherlands Heart Foundation.
The (Wrong) Choice of Decaf Coffee Can Raise Your Bad Cholesterol Level
Tue, Aug 18, 15 by Jim Couch
Who would ever think that the choice made in selecting a decaf coffee would make a difference in the level of your LDL cholesterol?
Apparently so, from research findings by Dr. H. Robert Superko of the Fuqua Heart Center in Atlanta. This goes back to a study in 2005 led by Dr. Superko and presented to the American Heart Association.
In the study, 187 coffee drinkers were randomly assigned to three groups of people and studied for an eight week period: those who daily drank three to five cups of decaf coffee; those who drank the same amount of caffeinated coffee; and those who drank no coffee. No creamers of sweeteners were used by the coffee drinkers, just black.
Results of the eight week study showed no change among the three groups in levels of triglycerides, HDL, glucose, or insulin — but there were significant increases in the level of the bad LDL cholesterol among the decaf drinkers.
So, why would that be? Why would drinking decaf raise your cholesterol? Dr. Superko speculated in an interview that the decaf coffee was of the Robusta species of coffee beans, which has a higher dipertene, or fat content, than does coffee made from the Arabica species. Apparently the coffee drinkers who drank caffeinated coffee in the study drank coffee from the milder, more expensive Arabica beans.
The health message here would be to understand what type of bean is used in your decaf, and choose Arabica. Typically, decaf coffees are made from Robusta beans, and you may need to look closely to see if you’re drinking Arabica-based decaf. HealthWise Swiss Water Process decaf is 100% Colombian coffee, and since Colombian only produces Arabica, no need to worry if you drink HealthWise decaf.
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
In a video I did a decade ago—you can tell how ancient it is by the silly graphics—I explained that the “cholesterol-raising factor” in coffee “does not pass a paper filter.” Give people French press coffee, which is filtered, but without paper, and their cholesterol swells up over time, starting within just two weeks. But switch them to paper-filtered coffee, and their cholesterol comes right back down. Same amount of coffee, but just prepared differently.
“The cholesterol-raising factor from coffee beans” has since been identified: it’s the fatty substances in the oil within coffee beans. One reason it took us so long to figure that out is that it didn’t raise cholesterol in rats, or hamsters, or even monkeys—but it did in human beings. But, it apparently gets stuck in the paper filter. “This explains why filtered coffee doesn’t affect cholesterol, whereas…’boiled’, , and Turkish coffees do.” Espresso, as well, which has 20 times more of the cholesterol-raising substance cafestol than paper-filtered drip coffee, with Turkish and boiled coffee being the worst—though instant and percolator coffee are pretty low, even without the paper filter.
Note: if you make drip coffee with one of those metal mesh filters without the paper, it would presumably be just as bad as like the French press.
So, the studies in general “appeared to consistently find” that it was this fatty component that was then filtered out by paper. But, “a small number of studies suggested that filtered coffee may also increase cholesterol levels, and began to cast some doubt on what appeared to be a fairly clear picture.” So, yeah, “the cholesterol-raising effects brought about by the consumption of filtered coffee may not be as strong as that of the boiled coffee.” But, maybe we shouldn’t “discard the possibility that filtered coffee may also play a small but important role” in raising cholesterol.
I knew about this study, where three cups a day of filtered coffee raised total cholesterol, but the rise in LDL “bad” cholesterol was not statistically significant. Same with this study, where stopping filtered coffee reduced total cholesterol, suggesting perhaps only partial removal. But, no one had ever just measured the levels of the cholesterol-raising compounds in the paper filters…until, now.
The results showed that most of the cholesterol-raising cafestol was retained by the coffee grounds, rather than getting stuck in the filter itself. In other words, “the principal function of the paper filter” is to not necessarily block the compound itself, but to block any fine particles that are carrying the compound. Like, when you make French press coffee, there’s that fine mesh screen, but you still notice a little sludge at the bottom of the cup; that’s the tiny particles that pass through and can carry some of the risk. But, a little cafestol does get through the filter.
So, yeah, you can cut out more than 90% by switching from French press, or one of the metal mesh filters, by using a paper filter. If you use coffee that starts out with a high level of the cafestol compound, you’re still clearing out about 95% with the paper, but there may be enough left to still bump up your LDL. But, you don’t know until you…put it to the test.
They started out with a high cafestol coffee. After a month of drinking two cups a day, their LDL cholesterol went up, significantly, even though it was paper-filtered. So, if you have high cholesterol despite eating a healthy diet, you may want to try cutting out coffee, and getting retested.
Or, you can try switching to a lower-cafestol coffee. There’s all sorts of variables, such as roasting degree or grind size that may affect cafestol levels. One can imagine a smaller particle size would allow for greater extraction. Roasting appears to destroy some of it. So, a really dark roast should have less. But, there’s not much difference between just light and medium roast. Indeed, in this study, there was no significant difference between the rise in cholesterol after a medium light roast and a medium roast. They both raised bad cholesterol.
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Drink more tea to lower cholesterol: VUMC study
BY: JESSICA PASLEY
6/27/2003 – A clinical trial testing a theaflavin-enriched green tea extract, led by a Vanderbilt University Medical Center researcher, is the first human study to find that a tea product lowers low density lipoprotein (LDL) cholesterol.
The double-blind, randomized, controlled study included 240 men and women with high cholesterol levels in China. During the 12-week trial, participants, already on a low-fat diet, were randomly chosen to receive either a 375 mg soft gel capsule or a placebo.
Dr. David J. Maron, associate professor of Medicine at VUMC, was the lead author.
The results, reported in the Archives of Internal Medicine this month, amazed him.
Personally, I was very surprised, Maron said. I expected, if anything, a very slight cholesterol-lowering effect. But what we saw was a 16 percent reduction in LDL cholesterol.
Tea is the second most widely consumed beverage worldwide, according to Maron. In the past, several epidemiologic studies had shown that tea consumption is associated with lower cholesterol. Experiments in animals have demonstrated that green tea, black tea, and flavonoids derived from green and black teas lower cholesterol. However, previous tea-drinking experiments in humans as well as those experiments involving the administration of green tea extract have failed to show any effects on cholesterol.
The 375 mg capsule used in this study is an extract made up of 75 mg of theaflavins (flavonoids from black tea), 150 mg of catechins (flavonoids from green tea) and 150 mg of other tea polyphenols. It is equivalent to 7 cups of high-quality black tea or 35 cups of green tea.
The National Cholesterol Education Program recommends a diet as the initial therapy for lowering LDL cholesterol in people without heart disease, said Maron. Prior to drug therapy, the guidelines recommend viscous fiber and plant stanol or sterol (margarine) to lower LDL further if the LDL goal is not achieved with diet.
Maron said there is a need to identify additional non-drug options for cholesterol lowering that have sufficient safety and efficacy data. There is also a need to find products that are more practical for the consumer than viscous fiber and plant stanols/sterols, he said.
Maron applauds the process by which the extract was evaluated.
The present study represents the first step in establishing the practicality, safety and LDL-lowering ability of this tea product.
While pleased with the initial outcomes, he recommends further testing to determine long-term safety, the effective dosing range, the impact when the extract is taken with lipid medication (especially statins) and the adaptability to other ethnic and patient groups.
Although the results are exciting, we do not want people to take the extract in place of their medications, he said. Unlike statins, this product has not been proven to prevent heart attacks or stroke, or to prolong life. The study shows that the tea extract is a useful adjunct to lowering LDL in people with high cholesterol already on a low-fat diet.
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Green tea may lower heart disease risk
Published: December, 2012
Here’s what studies have revealed about this popular beverage.
Lowering your risk of cardiovascular disease may be as easy as drinking green tea. Studies suggest this light, aromatic tea may lower LDL cholesterol and triglycerides, which may be responsible for the tea’s association with reduced risk of death from heart disease and stroke.
What the evidence shows
A number of studies have looked at possible links between green tea and cardiovascular disease.
A study of 40,530 Japanese adults found that participants who drank more than five cups of green tea a day had a 26% lower risk of death from heart attack or stroke and a 16% lower risk of death from all causes than people who drank less than one cup of green tea a day.
Last year, a meta-analysis of observational studies—13 conducted in green tea drinkers and five in black tea drinkers—found that people who drank the most green tea had a 28% lower risk of coronary artery disease than those who drank the least green tea. Black tea had no effect on heart risk.
Another 2011 meta-analysis of 14 randomized, placebo-controlled clinical trials found that green tea significantly lowered LDL cholesterol and triglyceride levels. Many of the studies had been conducted with capsules containing catechins, the active polyphenols in green tea, rather than with the beverage itself.
“The limited data available on green tea support a potential association between green tea and beneficial properties in relationship to risk factors for cardiovascular disease,” says Kathy McManus, director of the department of nutrition at Brigham and Women’s Hospital.
Although no serious side effects were reported in the studies, catechins have been reported to raise liver enzymes in animals. Green tea is also a major source of oxalate, which can cause kidney stones. This suggests that drinking more than five cups of green tea a day (or taking the equivalent in catechin capsules) might have more risks than benefits. When consumed wisely, though, green tea may improve your cardiovascular health.
“The bottom line is that no serious red flags were seen in the amount of tea they were testing. It appears that a few cups a day may be beneficial,” says McManus.
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Data from 1,536 participants indicated that green tea consumption was associated with an average systolic blood pressure 1.94 mmHg lower than placebo, but no benefits on diastolic blood pressure were observed.
In addition, green tea consumption was also associated with lower total and LDL cholesterol levels, compared to placebo, report scientists from the University of Oxford in the UK and the University of Washington in Seattle in Nutrition, Metabolism and Cardiovascular Diseases.
“The available evidence from RCTs suggests that dietary supplementation with green tea generates significant reductions on systolic blood pressure, total and LDL cholesterol,” wrote the researchers. “The effect size on systolic blood pressure is small, but the sizes of the effects on total and LDL cholesterol appear moderate.
“There is some evidence that daily consumption of 5-6 cups of green tea could result in reductions in systolic blood pressure, total cholesterol, and LDL cholesterol,” they added. “However, at this time green tea should not be recommended as a substitute for current management of patients with established hypertension or dyslipidaemia.”
The review appears in line with the ever-growing body of science supporting the potential benefits of green tea and its constituents, most notably EGCG (epigallocatechin gallate). To date green tea has been linked to a reduced risk of Alzheimer’s and certain cancers, improved cardiovascular and oral health, as well as benefits in weight management.