CGA have strong effects in the body on insulin metabolism, use of body fat as fuel, and weight loss. CGA in green coffee beans, the highest common source, range from about 60-90 mg/g. Amounts vary, however, by area grown, species, and year. Some green coffee beans have little CGA, and zero effects on weight loss (1-3).
Roasting of coffee beans destroys most of the CGA. (4) So you cannot use roasted beans or ground coffee itself as a source of CGA. Hence all the hype using green, unroasted, coffee beans for weight loss.
Rapid advances in analytic techniques over the last ten years (5,6), have enabled good biochemists to separate beneficial effects of CGA from effects of caffeine. The chemistry is very complex, however (7). Consequently many companies have made a complete mess of it.
Because of the very large profit potential in the burgeoning weight loss market, many CGA products have been improperly extracted and rushed to sale. Recently, the Federal Trade Commission found that even some products distributed under standardized brands, from good laboratories, have been adulterated by distributors. These adulterations produce worthless products with very low CGA.
Consequently, if you intend to buy green coffee bean products, investigate the company selling them thoroughly. Many companies who never did the chemistry before, have jumped on the bandwagon and are producing useless weight loss supplements.
With the profit motive in mind, and millions to be made, many new companies have also sprung up, specifically to sell green coffee beans. Investigate them well, because they have all the rah-rah, beautiful graphics, superb packaging, and false claims. Some of these companies were not even in the nutrition business before, and employ no biochemists, and have zero knowledge, and zero quality control. They simply buy green coffee bean powder, much of it from China, and most of it useless.
If you have already bought and used a green coffee bean product for weight loss, and you are not getting good results, it is likely from one of these sham companies. You should buy only from well- established nutritional companies, with at least a decade of quality products, and a spotless consumer record. In other words, buy only from companies that have a reputation to lose.
THE RUSH TO SCAM SALES OF GREEN COFFEE BEAN PRODUCTS
The rush to profit began after a 2012 study, published in a reputable journal (29). In this famous placebo controlled, crossover study, much quoted by the media, 8 men and 8 women receiving 1050 mg of green coffee extract per day, lost an average of 17.6 lbs – more than 10% of their body weight—and 4.44% of their body fat – in just 6 weeks.
Such massive losses seemed too good to be true, except that the study was apparently almost duplicated by Dr Oz on television, which sent sales through the roof. In 2014, the Federal Trade Commission found the Dr Oz “study” to be completely false, and fined him and his associates $9 million for their deception. The original study that triggered this hoopla, was also withdrawn for the learned journal in October 2014, as the authors could not demonstrate the authenticity of the data (30).
REAL CGA WORKS WELL
Real CGA does work. In both animal and human studies, CGA have shown strong anti-inflammatory (7,8), blood sugar lowering (9,10) and body fat reduction (10-12) effects, all of which are disordered in overweight. In animal studies, CGA have clear anti-diabetic effects on insulin resistance and on lipid metabolism (11-14).
Glucose-6-phosphatase, for example, is the major enzyme for releasing glucose into the blood from the liver. This enzyme, helps regulate blood sugar in active young adults.
In older people, over age 35 however, it triggers an unhealthy after-meal surge in blood glucose. This surge becomes progressively worse as we age. GCA have been shown in numerous controlled trials to regulate glucose-6 phosphatase and lower blood glucose in vitro, and in live animal, and human, trials (23-26).
CGA powder can be added to ground coffee after roasting with significant benefits for weight loss (27). Keurig and similar systems can prepare delicious coffee at a lower temperature than expresso machines, and quicker than drip percolators. Consequently, they provide a less destructive vehicle for delivery of CGA from powder added to the pod.
CGA added to coffee before brewing coffee also yields a better tasting coffee, because CGA provide much of the flavor and aroma of coffee in any case. We use 200 mg of potent CGA powder per 8-ounce cup of coffee, tipped into the central hole made by the Keurig machine before brewing. Drink this java daily in good faith that it will help you maintain ideal weight.
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