Green coffee bean
extract is a new ingredient on the
market. It has strong anti-oxidant properties similar to other
natural anti-oxidants like green tea and
grape seed extract.
These beans have polyphenols which act to help reduce free oxygen
radicals in the body (in other words acting as good antioxidants). Green coffee bean extract is sometimes standardized to
30 to 50% chlorogenic acid,
a compound present in
coffee which has long been known for its beneficial properties.
Boiled
coffee drinks contain cafestol which is associated with the negative effects of
using coffee as a stimulant, this is not present in green coffee beans or
the extract.
This natural supplement has been mentioned on the Dr. Oz TV program
several times as a potential fat burner that helps with weight loss. Is this
claim true or are the claims overly enthusiastic? The hype began in September
2012 when Dr. Oz nationally introduced green bean coffee extract as a "fat
burner that helps women lose weight." It now appears that the promises
exceeded the actual benefits.
A search on Medline in 2015 did not reveal any new human
experiments with this product since 2012.
Availability by herb and vitamin suppliers
Green coffee bean is sold in a variety of extracts usually from 30 percent
to 50 percent chlorogenic acid concentration. For appetite control I suggest
Diet Rx which is more effective.
Buy
Green Coffee Extract pills, high quality, or Diet Rx which is a more potent
appetite suppressor
Research and benefit
Although this supplement has been promoted as a weight loss pill,
there is only limited human research regarding this potential benefit.
If you truly wish to shed some pounds, a comprehensive dietary and
lifestyle approach is necessary as mentioned in this article on natural
weight loss
Review of studies regarding its influence on body
weight - retracted study
Diabetes Metabolic Syndrome Obesity 2012.
Randomized, double-blind, placebo-controlled, linear dose, crossover study to
evaluate the efficacy and safety of a green coffee bean extract in overweight
subjects.
Department, University of Scranton, Scranton, PA, USA.
A 22-week crossover study was conducted to examine the efficacy and safety of a
commercial green coffee extract product GCA™ at reducing weight and body mass in
16 overweight adults. Subjects received high-dose GCA (1050 mg), low-dose GCA
(700 mg), or placebo in separate six-week treatment periods followed by two-week
washout periods to reduce any influence of preceding treatment. Significant
reductions were observed in body weight, body mass index, and
percent body fat, but with no significant changes to diet over the course of the
study. The results suggest that GCA
may be an effective nutraceutical in reducing weight in preobese adults, and may
be an inexpensive means of preventing obesity in overweight adults.
Diabetes Metab Syndr Obes. 2014. Randomized, double-blind, placebo-controlled, linear dose, crossover study to evaluate the efficacy and safety of a green coffee bean extract in overweight subjects [Retraction] This retracts the article "Randomized, double-blind, placebo-controlled, linear dose, crossover study to evaluate the efficacy and safety of a green coffee bean extract in overweight subjects" in volume 5 on page 21, which was published in final edited form. Vinson JA, Burnham BR, Nagendran MV. Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy. 2012. The sponsors of the study cannot assure the validity of the data so we, Joe Vinson and Bryan Burnham, are retracting the paper.
BMC Complement Altern Med. 2006. Inhibitory effect of green coffee bean extract on fat accumulation and body weight gain in mice.
High blood pressure benefit
Perhaps it may have some benefit in lowering blood pressure, but certainly more
studies are needed to confirm initial findings.
Clin Exp Hypertens. 2006. The blood pressure-lowering effect and safety of
chlorogenic acid from green coffee bean extract in essential hypertension.
Health Care Products Laboratories, Kao Corporation, Tokyo, Japan.
Chlorogenic acids (CGA) in green coffee bean extract (GCE) reduce blood pressure
in spontaneously hypertensive rats and humans. The authors examined the blood
pressure-lowering effect and safety of CGA in patients with mild hypertension
through a placebo-controlled, randomized clinical trial. Subjects were
randomized to receive treatment with CGA (140 mg/day) from GCE or placebo. Blood
pressure, pulse rate, body mass index, routine blood test, hematochemistry,
urinalysis, and subjective symptoms were recorded throughout the study. In the
CGA group, but not the placebo group, blood pressure (systolic and diastolic)
decreased significantly during the ingestion period. There was no difference in
body mass index and pulse rate between groups, nor were there any apparent side
effects. Thus, CGA from GCE is effective in decreasing blood pressure and safe
for patients with mild hypertension.
Hypertens Res. 2005. Antihypertensive effect of green coffee bean extract on mildly hypertensive subjects.
Improved blood vessel action, circulation
Green coffee bean extract improves human vasoreactivity.
Hypertension Research. 2004.
Green
coffee bean extract contains chlorogenic acid as a major phenolic
compound, and it in turn contains ferulic acid as a metabolic component
that acts on nitric oxide (NO) derived from the vascular endothelium. In
this study, the effects of green coffee bean extract on blood vessels were
evaluated in healthy males. The subjects were 20 healthy males with
reduced vasodilation responses measured by strain gauge plethysmograms (SPG)
to ischemic reactive hyperemia. Of the 20 subjects, 10 ingested a test drink containing green coffee bean extract (chlorogenic
acid 140 mg/day), and the other 10 ingested a placebo
drink for 4 months. During the ingestion period, SPG, pulse wave velocity
(PWV), and serum biochemical parameters were measured, and acceleration
plethysmograms (APG) were taken. The reactive hyperemia ratio (RHR) in the
test drink group began to increase after ingestion for 1 month and was
significantly higher than that in the placebo group after ingestion for 3
months and 4 months. In addition, after ingestion for 4 months, the test
drink group showed a significant decrease in the plasma total homocysteine
level compared with the pre-ingestion level. However, there were no
significant differences in PWV or APG between the test drink group and the
placebo drink group. The improvement in RHR after ingestion of a drink
containing GCE suggested an improvement in vasoreactivity by this
component.
Diabetes and blood sugar
Dietary supplementation with decaffeinated green coffee improves
diet-induced insulin resistance and brain energy metabolism in mice. Nutr
Neuroscience. 2012.
What do the beans contain?
Polyphenols including chlorogenic acids (caffeoylquinic acids and
dicaffeoylquinic acids). Chlorogenic acids are cinnamic acid derivatives with
biological effects mostly related to their antioxidant and antiinflammatory
activities. Caffeoylquinic acids and dicaffeoylquinic acids are the main
chlorogenic acids found in nature.
Contains
caffeine (I think the amount of caffeine is small but I am not sure
yet) which has positive and negative attributes depending on
dosage used, timing, and frequency.
Green coffee bean extract is made from the green beans of the coffea Arabica plant. There are two types of coffee plants, arabica and robusta... the arabica is higher in quality and higher in chlorogenic and caffeic acids, two primary compounds responsible for anti-oxidant activity.
My experience and side effects
I have only take this natural product two days in a row, 2 pills in the
morning. I did notice appetite suppression but it was mild compared to Diet Rx.
I also noticed feeling more alert and my vision was clearer. Side effects may
include shallow sleep if taken later in the day. I tried it several months later
and again I noticed slight visual clarity within an hour of taking two pills.
Interview questions asked by a magazine writer:
Can people really lose weight with these green coffee beans or is it just
over-hyped about and does less than people think?
The research on this topic is quite limited, just a handful of
studies have been done on the use of green coffee bean extract supplements and
weight loss in humans. Even though there have been positive results, I prefer
having a chance to review a few more before having more confidence.
What's the magic ingredient in green coffee beans that
makes weight loss possible?
It's probably a combination of several ingredients including
chlorogenic acids and caffeine.
If green coffee beans are so healthy for people, why don't they sell them in
stores?
I don't know much about their availability in coffee shops but they
are sold over the counter as dietary supplement pills.
As a doctor, have any of your patients used green coffee
beans? If yes, can you tell me their experience with it?
Thus far no major side effects have been mentioned in the medical
literature, but, as with any new dietary supplement, when hundreds of thousands
of new people start using it with many of these individuals taking various
medications or having existing medical conditions such as heart disease or
hormone imbalances, it is possible adverse reactions could occur in some
individuals that at present are difficult to predict.
Questions
Can a green coffee extract be taken the same day as
tongkat ali,
choline,
dmae, or
carnosine and
other dietary supplements and herbal medicines? I
forgot to ask about saw
palmetto.
Many of these nutrients and herbs you mention above are very
stimulating, so it would be preferable not to take them the same day or to
take lower dosages.
Is coffee a functional food?
The worldwide use of coffee for social engagement, leisure,
enhancement of work performance and well-being is widely recognized. Depending
on the quantities consumed, it can affect the intake of some minerals (K, Mg, Mn,
Cr), niacin and antioxidant substances. Epidemiological and experimental
studies have shown positive effects of regular coffee-drinking on various
aspects of health, such as psychoactive responses (alertness, mood
change), neurological (Alzheimer's and Parkinson's
diseases) and metabolic disorders (diabetes, gallstones, liver cirrhosis),
increase the effectiveness of pain killers, especially for migraine
medications, and gonad and liver function. Despite this, most reviews do not mention
coffee as fulfilling the criteria for a functional food. Unlike other
functional foods that act on a defined population with a special effect,
the wide use of coffee-drinking impacts a broad demographic (from children
to the elderly), with a wide spectrum of health benefits. However, there
is a down side to coffee drinking. It can cause anxiety and blood
pressure problems, and it could also cause or aggravate heart rhythm
abnormalities. Hence, it is possible to claim that coffee, when limited to
one cup a day could be considered a
functional food,
but not when 3 or more cups are drank a day, particularly if the coffee is
ingested later in the day and causes insomnia.