You already know that green tea is a potent antioxidant and has been used to enhance health for thousands of years. You may also know that green tea is a potent antioxidant for supreme immune system support. But did you also know it’s one of the most powerful cholesterol-busting nutrients nature has to offer? And if that’s not enough, green tea improves triglycerides and total cholesterol numbers too!
Background
Chinese herbal green tea has notably become the “supplement of choice” for many seeking greater health and control over their weight. For good reason: it has an interestingly appealing flavor when prepared as tea. Also, science defends some astounding benefits when it’s used as a supplement for immune enhancement, and fat mobilization and cholesterol reduction.
Botanical evidence indicates that India and China were among the first countries to cultivate tea. Today, tea is the most widely consumed beverage in the world. Hundreds of millions of people drink tea around the world and studies suggest that green tea (Camellia sinesis), in particular, has many health benefits.
There are three main varieties of tea — green, black, and oolong. The difference between the teas is in their processing. Green tea is made from unfermented leaves and reportedly contains the highest concentration of powerful antioxidants called polyphenols.
Antioxidants are substances that scavenge free radicals – damaging compounds in the body that alter cells, tamper with DNA (genetic material), even causing cell death. Free radicals occur naturally in the body, but environmental toxins (including ultraviolet rays from the sun, radiation, cigarette smoke, and air pollution) also give rise to these damaging particles. Many scientists believe that free radicals contribute to the aging process as well as the development of a number of health problems, including cancer and heart disease. Antioxidants such as polyphenols in green tea can neutralize free radicals and may reduce or even help prevent some of the damage they cause.
Cholesterol Reduction
Frankly, I love green tea and it’s one of the best health-enhancing nutrients you can take. In addition to its heart health benefits, it stimulates your immune function, supports healthy blood sugar levels, and combats mental fatigue.
Polyphenols are 40 times stronger than both vitamin C and E in their ability to mop up dangerous free radicals that can damage your heart. The polyphenols in green tea fortify your heart cells so they keep on producing maximum energy and burn up the extra-oxidized LDL cholesterol that sticks to your artery walls like glue.
Not only can green tea helps scrub your arteries clean, it also helps dissolve any new blockages that may occur. In fact, researchers at UCLA and Cedars Sinai Medical Center found that green tea polyphenols can prevent up to 73% of high cholesterol buildup and new blockages in arteries.
And if that’s not enough, according to a University of Connecticut study, the compounds in green tea help block bad cholesterol from being absorbed in the blood and digestive tract and helps excrete it from the body. Another study conducted by the prestigious Vanderbilt University Medical Center found that patients taking green tea extracts saw their levels of “bad” LDL levels and total cholesterol plummet an average of 11 percent. Plus, a study published in the Journal of Nutrition says that green tea can reduce triglycerides as much as 20%.
As you may know, triglycerides are another important predictor of heart health. They are fatty particles that come mostly from sugars, carbohydrates and alcohol in your diet. They usually end up stored as body fat. High triglycerides can dramatically impact the health of every artery in your body. That’s why keeping triglycerides at healthy levels is one of the best things you can do for your heart – and green tea can help.
Green tea extracts, which are rich in natural antioxidants and anti-platelet agents, are routinely used in Asia to lower blood pressure and reduce elevated cholesterol. In studies of smokers, 600 ml of green tea (not extract) was shown to decrease markers of inflammation and decrease oxidized cholesterol – both of which are intimately involved in the development of atherosclerosis (Lee W et al 2005b).
A Japanese study of 203 patients found that the more green tea patients drink, the less likely they are to suffer from coronary artery disease (Sano J et al 2004). This study supported an earlier study that found that greater green tea consumption was related to a reduced presence of coronary artery disease in Japanese men (Sasazuki S et al 2000).
There was a recent study on a group of men who drank green tea regularly. It was found that these men had much lower cholesterol levels than the men who did not drink green tea. There also was another study performed on men and women who had high cholesterol levels. Some of the participants were selected randomly to receive a placebo or a soft gel capsule ofcatechins. Catechins are extracts that is obtained from green tea leaves. This study showed that the participants who took the extract capsule had significant lower cholesterol levels. It has been proven that green tea polyphenols can also stop the bad cholesterol from entering the intestines and blood stream.
Green tea also has epicatechins which can help in the rapid release of fatty acids and bile salts that contain traces of cholesterol. The benefits of green tea also have been shown in the French culture where fatty diets are evident. French people have less heart disease and high cholesterol levels than Americans and it was later discovered that green tea was a tool in achieving this. Many cultures drink green tea and it is possible to find this tea in most countries. Green tea can also reduce toxins in the body and can help people overcome many other diseases or prevent them from occurring. It can aid in cholesterol reduction and even assist in weight loss programs. This is why green tea extracts are used in our artery products.
How it Affects Cholesterol Production
In addition to the mechanisms described above, Dr. Tomonori notes that EGCG also inhibits an enzyme that controls the rate of cholesterol production. He recommends additional research to determine how EGCG ameliorates cardiovascular risk factors and to study the effects of green tea in non-Japanese nationalities. “The most important treatments for obesity and cardiovascular diseases should be obtained by an appropriate lifestyle such as balanced diet and exercise habits,” Dr. Tomonori says. “Continuous ingestion of a [green tea extract] high in catechins might assist this.”
The largest population-based study to date of the effects of green tea on life span is the Ohsaki study of more than 40,000 Japanese adults followed for up to 11 years. When enrolled in 1994, participants were 40 to 79 years old and had no history of stroke, coronary heart disease, or cancer. The study found that drinking more green tea protected against death from all causes and against death from cardiovascular disease, particularly from stroke, but not against death from cancer.
During follow-up, there were 12% fewer deaths from all causes in men and 23% fewer deaths in women who drank five or more cups of green tea per day, compared with those who drank less than one cup. Even more strikingly, there were 31% fewer cardiovascular deaths in women who drank five or more cups per day, compared with those who drank less than one cup.
Lead investigator of this study, Shinichi Kuriyama, MD, PhD, said, “We have confirmed that green tea consumption is associated with reduced mortality due to all causes, cardiovascular disease, but not cancer. Our study provides strong evidence regarding benefits of drinking green tea in humans on cardiovascular disease, but not cancer.”
Dr. Kuriyama, an associate professor of Epidemiology, Public Health, and Forensic Medicine at Tohoku University Graduate School of Medicine in Sendai, Japan, points out that previous studies have suggested green tea may reduce cardiovascular risk factors such as hypertension and obesity. This may partly explain improved survival linked to green tea consumption. Surprisingly, however, his study showed a protective effect of green tea drinking even in lean subjects and in those with normal blood pressure.
“Therefore, mechanisms other than the effects on traditional cardiovascular disease risk factors might play a role,” Dr. Kuriyama says. “A number of biological mechanisms including radical scavenging and antioxidant properties have been proposed for the beneficial effects of green tea in different models of chronic disease. Green tea polyphenols might directly affect atherosclerosis itself, irrespective of traditional cardiovascular disease risk profiles.”
Extended Cholesterol and Cardiovascular Discussion
(The following is a little more technical, with references following, for those interested.)
Green tea acts in many ways to promote cardiovascular health. Thanks to potent antioxidant activity, green tea and EGCG scavenge damaging free radicals, or reactive oxygen species that cause cellular injury leading to heart disease. Heart disease can develop in many ways, such as:
• Inflammation of blood vessel walls and proliferation of the muscle cells within blood vessel walls, which contribute to atherosclerosis.
• Endothelial dysfunction and constriction of blood vessels, which reduce blood flow to the heart muscle and increase blood pressure.
• Abnormal platelet aggregation within blood vessels, which can lead to a deadly heart attack or stroke.
• High levels of low-density lipoprotein (LDL), particularly when oxidized, which further aggravate all of these problems.
Amazingly, green tea can help protect against all of these culprits leading to heart disease and stroke. In a well-controlled study, human volunteers showed short-term improvements in blood flow with EGCG compared with placebo.
“Green tea has been reported to beneficially impact parameters associated with cardiovascular dysfunction including lipoprotein oxidation, vascular inflammation, proliferation of vascular smooth muscle cells, platelet aggregation, and vascular reactivity. Catechins, the major polyphenolic compounds in green tea, exert vascular-protective effects through multiple mechanisms including antioxidative, anti-inflammatory, antithrombogenic, antiproliferative and lipid-lowering effects. Green tea catechins were also reported to regulate vascular tone.” Dr. Babu says, referring to his own laboratory studies.
Epigallocatechin gallate also activates endothelial nitric oxide synthase in cells lining blood vessels, or endothelial cells, which Dr. Wolfram says may partially explain the cardiovascular benefits of green tea consumption. Increased release of nitric oxide causes smooth muscle within the blood vessel wall to relax, thereby increasing the diameter of the blood vessel and improving blood flow.
Another important mechanism may be that EGCG reduces the expression of cellular chemicals known as cytokines, which promote inflammation underlying atherosclerosis and heart disease. Epigallocatechin gallate may therefore inhibit inflammation and proliferation of smooth muscle cells within the blood vessel wall, thereby preventing vascular blockage.
“Green tea and EGCG were shown to reduce atherosclerosis and improve arterial compliance and endothelial function. Regular green tea consumption is associated with reduced risk of cardiovascular disease such as stroke and myo-cardial infarction [heart attack].” Dr. Wolfram says.
In further research, a clinical trial led by Japanese researcher, Nagao Tomonori, evaluated the effect of a green tea extract rich in catechins on risk factors for cardiovascular disease. “The continuous ingestion of [green tea extract] reduces body fat, cholesterol levels, and blood pressure in females and males without changing their lifestyles. We found that increased beta-oxidation (fat burning) in the liver by catechins was associated with the reduction of intra-abdominal body fat, [which] is known to secrete factors causing various chronic diseases. Therefore, its reduction will reduce the risk of lifestyle-related chronic disease.”
A-Z Index, – under “Artery Plaque Reduction”, and “Cholesterol – High Cholesterol Formula“, or:
Artery Plaque Reduction – to help dissolve and remove artery cholesterol.
High Cholesterol Formula – how to lower and maintain cholesterol levels.
References:
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