Green coffee bean extract's therapeutic uses

  • DEFINITION: Natural plant product used to treat specific health conditions.
  • PRINCIPAL PROPOSED USE: Hypertension
  • OTHER PROPOSED USES: Antioxidant, anti-inflammatory, blood sugar control, diabetes prevention, weight loss

Overview

Just as black tea is made by processing green tea leaves from their original state, ordinary coffee is made by roasting green coffee beans. This processing alters the chemical makeup of the plant product. In an analogy to the medicinal study of green tea, an extract made from green coffee beans is undergoing increasing investigation as a possible health-promoting supplement.

Like green tea, green coffee bean extract (GCBE) contains strong antioxidants in the polyphenol family. The primary polyphenol antioxidants in green coffee bean extract are in a family known as chlorogenic acids (CGA). Meaningful, if still preliminary, evidence hints that CGA may help reduce blood pressure. Other proposed uses of GCBE were once based primarily on its caffeine content and observational studies of ordinary coffee consumption and the possible health benefits of antioxidants in general. However, double-blind, placebo-controlled trials of GCBE have emerged, showing efficacy for weight management, blood sugar control, and cardiovascular health.

Therapeutic Dosages

In a large human trial of GCBE for hypertension, the extract was most effective when taken at a dose of 185 milligrams (mg) daily.

Therapeutic Uses

Animal studies have found evidence that chlorogenic acids from GCBE can reduce blood pressure, which has led to researchers conducting human trials.

In a double-blind, placebo-controlled study of 117 males with mild hypertension, GCBE was given for one month at 46 mg, 93 mg, or 185 mg daily. After twenty-eight days, the results showed a significant improvement in blood pressure, compared with placebo, in the 93-mg and 185-mg groups. The results were dose-related, meaning that the greater the dose, the greater the improvement. The dose-related finding tends to increase the likelihood that a studied treatment is effective. Antihypertensive benefits were also seen in a much smaller study using purified chlorogenic acids.

GCBE has also shown some promise for aiding weight loss, perhaps in part due to its chlorogenic acid content. A 2020 study appeared to confirm that GCBE could interfere with carbohydrate and fat absorption, leading to weight loss. The caffeine in GCBE might also provide a slight weight-loss benefit.

GCBE products are sometimes said to help prevent diabetes. Additionally, roasted (as opposed to green) coffee beans contain the substances kahweol and cafestol, which appear to increase levels of low-density lipoprotein (LDL, or bad cholesterol). The fact that GCBE does not contain these substances is used as an argument in its favor. However, these substances remain in the coffee grounds and are also not present in standard beverage coffee, so this is probably not a significant point. (Unfiltered or boiled coffee, with the grounds left in, however, may present a risk.) Still, double-blind, placebo-controlled trials of GCBE for cardiovascular benefits and benefits for blood sugar control produced promising results.

Since green coffee bean extract typically contains about 30 percent chlorogenic acids, this works out to a daily dose of about 60 mg of chlorogenic acids. Another study used 140 mg of purified chlorogenic acids daily.

A 2021 study appeared to validate many of the above claims and showed that green coffee improved total cholesterol, managed blood pressure, and improved fasting plasma glucose. Finally, GCBE has antioxidant and anti-inflammatory properties that have been shown to protect against free radicals that cause chronic health conditions.

Safety Issues

GCBE is thought to be safe. In human trials, no significant adverse effects have been seen.

In theory, the caffeine content of GCBE could potentially cause problems for some people. However, since GCBE contains only about 10 percent caffeine by weight, a high daily dose contains no more than about 20 percent of the caffeine content in a strong cup of coffee. Maximum safe doses in pregnant or nursing women, young children, and people with liver or kidney disease have not yet been established. Many prescription medications and herbal supplements may interact with the caffeine content of GCBE, and patients are encouraged to discuss all medications with their healthcare provider. Additionally, several health conditions that may have adverse effects from caffeine consumption exist, and caution should be used. 

Bibliography

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