Life Extension Magazine

Life Extension Magazine 2011

Cover Story

Are We All Pre-Diabetic?

By Kirk Stokel

Green Coffee Extract Improves Glucose Control

Green coffee bean extract found in unroasted coffee beans, once purified and standardized, produces high levels of chlorogenic acid and other beneficial polyphenols that can suppress excess blood glucose levels.

The research findings on the impact of chlorogenic acid on blood sugar are impressive. For starters, a team of Japanese researchers recorded a 43% drop in blood sugar levels after administering green coffee bean extract to mice after a heavy meal.24

Figure 1

Human clinical trials support the role of chlorogenic acid-rich green coffee bean extract in promoting healthy blood sugar control and reducing disease risk.

Aware of the crucial importance of controlling after-meal blood sugar spikes, scientists conducted a study among 56 healthy volunteers, challenging them with an oral glucose tolerance test before and after a supplemental dose of green coffee extract. The oral glucose tolerance test is a standardized way of measuring a person's after-meal blood sugar response.

In subjects not taking green coffee bean extract, the oral glucose tolerance test showed the expected rise of blood sugar to an average of 144 mg/dL after a 30 minute period. But in subjects who had taken 200 mg of the green coffee bean extract, that sugar spike was significantly reduced, to just 124 mg/dL—a 14% decrease1 (See figure 1).

Figure 2

That impressive difference was sustained throughout the two-hour study period at a dose as low as 200 mg of green coffee bean extract. Subjects had a mean 19% reduction of blood sugar at one hour, and a 22% reduction (glucose down to just 89 mg/dL) at two hours, compared to each patient's own untreated levels. In other words, the amount of time subjects had glucose levels in the dangerous range was sharply curtailed by the green coffee bean extract1 (See figures 2 and 3).

To state this differently, when subjects did not take the green coffee bean extract, their oral glucose tolerance reading after two hours showed blood sugar of 115 mg/dL—a higher-than-desirable level. In response to a modest dose of 200 mg of green coffee bean extract, two-hour blood sugar levels dropped to only 89 mg/dL1 (See figure 3).

For most aging individuals, even after eating nothing for eight to twelve hours, it is challenging to achieve a "fasting" glucose reading as low as 89 mg/dL. Yet when these study subjects took 200 mg of green coffee bean extract, their glucose levels dropped to 89 mg/dL just two hours after drinking a pure glucose solution. The high-dose glucose drink used in standard oral glucose tolerance tests spikes blood sugar more than typical meals.

Figure 3

When a higher dose (400 mg) of green coffee bean extract was supplemented before an oral glucose challenge test there was an even greater average reduction in blood sugar—up to nearly 28% at one hour!1

How Green Coffee Bean Extract Suppresses Glucose Elevation

Scientists have discovered that chlorogenic acid found abundantly in green coffee bean extract inhibits the enzyme glucose-6-phosphatase that triggers new glucose formation and glucose release by the liver.25,26 As discussed earlier, glucose-6-phosphatase is involved in dangerous after-meal spikes in blood sugar.27

Another means by which chlorogenic acid acts to suppress after-meal glucose surges is by inhibiting alpha-glucosidase. This intestinal enzyme breaks apart complex sugars and enhances their absorption into the blood.28 Slowing the absorption of common sugars (including sucrose) limits after-meal glucose spikes.29

In yet another significant mechanism, chlorogenic acid increases the signal protein for insulin receptors in liver cells.30 That has the effect of increasing insulin sensitivity, which in turn drives down blood sugar levels.

Benefits and Limitations of High Coffee Consumption

Many epidemiologic studies suggest a benefit of consuming large amounts of coffee. Moderate to high amounts of coffee consumption is associated with a sharply reduced risk of developing type 2 diabetes.58-61 Laboratory studies suggest that coffee may have anti-tumor effects against ovarian, colon, liver, and other cancers.62-66 And coffee consumption may be associated with a decreased risk of stroke in women, while those who consume moderate amounts of coffee may be protected against acute coronary syndromes.67,68

For many people, drinking large amounts of coffee is not ideal.

Large amounts of caffeine may be irritating. One study found that people who drank 12 or more cups of coffee daily were getting a total of 960-1,380 mg of caffeine.69,70 For many individuals, high levels of caffeine consumption can be undesirable.

Additionally, it is important to note that the commercial process of roasting coffee beans creates a molecule called HHQ, that actually reduces some of the activity of the chlorogenic acid found in green coffee.71,72

A very low-caffeine extract derived from unroasted green coffee bean provides a standardized dose of beneficial chlorogenic acid.

Chlorogenic acid-rich plant extracts have been shown to reduce fasting blood glucose values by more than 15% in diabetic patients with poor response to medication.31 A similar effect was seen in healthy volunteers, whose intestinal absorption of glucose was reduced following a chlorogenic acid-enriched coffee drink.32

Impact of Green Coffee Bean extract

When a chlorogenic acid supplement of 1 gram was given before meals, glucose levels were reduced by 13 mg/dL, just 15 minutes after an oral glucose challenge, demonstrating its ability to rapidly lower the after-meal blood sugar spike in humans.33

In a clinical trial, researchers gave different dosages of green coffee bean extract, standardized for chlorogenic acid, to 56 people. Thirty-five minutes later, they gave the participants 100 grams of glucose in an oral glucose challenge test. Blood sugar levels dropped by an increasingly greater amount as the test dosage of green coffee bean extract was raised, from 200 mg up to 400 mg. At the 400 mg dosage, there was a full 24% decrease in blood sugar—just 30 minutes after glucose ingestion.1

This means that if you had a dangerous after-meal glucose reading of 160 mg/dL, green coffee bean extract would slash it to 121 mg/dL.

These findings are in line with supportive data demonstrating green coffee bean extract's numerous blood sugar-reducing mechanisms of action.

Disease Risks of High-Normal Blood Sugar

Cancer: Numerous studies—including one published in the May 17, 2010, online issue of The Oncologist that was so large that it included half of all type 2 diabetics in Sweden35—found that, separate from the known risks for cancer among diagnosed diabetics,36-38 the risk for some cancers escalated directly with blood sugar levels, even among those without diabetes. Rising in lock-step with glucose levels as they edged up within the normal range were the risks for cancers of the endometrium,39 pancreas,40 colon,41,42 and colorectal tumors of a more aggressive nature.43

Cardiovascular disease: Subjects showed risks for cardiovascular events, cardiovascular disease, and cardiovascular mortality that increased in direct relation to elevated—but still high-normal—glucose levels.44-48 One researcher commented that within limits, the lower the glucose levels—even among those without diabetes—the lower the cardiovascular risk. Coronary artery disease risk was twice as high in patients with post-meal glucose levels between 157 and 189 mg/dL compared to those with levels under 144 mg/dL.49 While diabetes is defined as experiencing regular after-meal glucose levels of 200 mg/dL, one research team found a risk for stroke that increased as fasting glucose levels rose above 83 mg/dL. In fact, every 18 mg/dL increase beyond 83 resulted in a 27% greater risk of dying from stroke.14

Cognitive impairment: As blood sugar rose—whether within the normal or the diabetic ranges—the risk for this mild cognitive impairment and dementia increased.50,51

Kidney disease: Surges in blood sugar promoted a greater production of fibrous kidney tissue—which causes kidney disease—than a high but constant blood sugar level.52 The study authors suggested it may be fluctuations in glucose—more than the levels themselves—that produce the vascular complications implicated in kidney damage. Another study found a direct increase in chronic kidney disease as levels of hemoglobin A1c (a marker of long-term glucose control) rose.53

Pancreatic dysfunction: Beta cells located in the pancreas produce the insulin that helps control blood sugar. But high glucose levels can make these cells dysfunctional, raising the risk of type 2 diabetes. Researchers discovered that mild beta cell dysfunction was already detectable in those whose glucose levels spiked two hours after eating, despite staying completely within the range considered by the medical establishment to be normal.54

Diabetic retinopathy: High glucose levels precipitate diabetic retinopathy—damage to the retina that can lead to blindness. In one study, retinopathy was diagnosed in 13% of people who later progressed to diabetes and in 8% of those who never progressed to diabetes.55

Neuropathy: As expected, patients with nervous system damage (neuropathy) whose postprandial (after-meal) glucose readings were above the diabetic threshold, showed damage to their large nerve fibers. However, neuropathy patients whose glucose readings—although elevated—remained well within the normal range still showed damage to their small nerve fibers. Within any blood sugar range, reported the journal Neurology in 2003, the higher the glucose, the greater the involvement of the large nerve fibers.56 Another nerve damage study in 2006 confirmed these results.57

Other experimental models reveal that chlorogenic acid favorably modulates gene expression to enhance the activity of liver cells and increase levels of the hormone adiponectin, which enhances insulin sensitivity and exerts anti-inflammatory, anti-diabetic, and anti-atherogenic effects.34

Summary

The need to redefine diabetes is critical because risk of premature death and disease rises sharply with fasting blood sugar greater than 85 mg/dL.

Furthermore, the insidious impact of after-meal blood sugar spikes goes largely undetected, exposing the vast majority of people to accelerated disease risk.

Behind this danger is the little-appreciated role of glucose-6-phosphatase in creating and releasing additional glucose into the blood. This enzyme, which helps regulate blood sugar when you're young, can inappropriately trigger a dangerous after-meal surge of blood sugar as you age.

Avant-garde scientists have identified a breakthrough weapon to control these surges: green coffee bean extract. This natural ingredient contains a compound called chlorogenic acid shown to target glucose-6-phosphatase and blunt post-consumption blood sugar levels by up to 32%.

A consistent finding in those who restrict their calorie intake is markedly lower blood glucose levels. Longevity enthusiasts can now benefit from a novel yet natural green coffee bean extract to combat internal processes that cause dangerous elevations in blood glucose.

If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.

Who Should Supplement with Green Coffee Bean Extract

Green coffee bean extract contains a natural compound (chlorogenic acid) that reduces blood sugar by inhibiting the glucose-6-phosphatase enzyme.

Glucose-6-phosphatase increases blood sugar by promoting the creation of new glucose (gluconeogenesis) and inducing the release of glucose stored in the liver (glycogenolysis).

Those with fasting glucose above 85 mg/dL, or whose oral glucose tolerance test shows two-hour postprandial glucose surges over 125 mg/dL, should consider taking 200 to 400 mg of standardized green coffee bean extract two to three times daily, thirty-five minutes before meals.

To clarify the postprandial (after-meal) risk, if your fasting glucose is 85 mg/dL, but an oral glucose tolerance test shows blood glucose above 125 mg/dL after two hours, then you are likely to be suffering from toxic after-meal glucose surges that can be neutralized by taking green coffee bean extract before most meals.

Most aging people suffer both fasting and postprandial glucose overload, and should initiate steps to suppress the dangerous glucose-6-phosphatase enzyme.

References

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