Strong aroma of coffee is a mood refill for many not leaving me. Coffee stands as one of the world’s popular beverages and is well known for that robust aroma. All that strikes to mind is caffeine once we think about coffee. Caffeine is a Central Nervous System (CNS) stimulant and coffee is well known source of caffeine that is needed for human body. Do you know that coffee we get in supermarket is actually the “roasted seeds” of coffee cherries? And the only reason we call them beans is their close resemblance to legumes and both are not really related to one another. The two so called “beans” are enclosed in the “fruit called cherry” that is borne on short pruned coffee shrubs. Flowering is a continuous process in these plants so we can find green fruits alongside of ripe fruits on waxy leaf covered branches. Beans are inside the medium sized pulp covered by layers of exo, meso and endocarp along with pectin layers.
Journey from cherry to hot mug
The bright deep red coloured cherries are hand-picked carefully from the coffee fields and dried to maintain a moisture content of 11%. By now the pulp and other outer layers are separated out and only beans are left for further process. Roasting is the process where green coffee beans turn into dark brown colour and beans gain that characteristic aroma. During roasting the beans are placed in a metal cylinder. Hot air ranging from 180- 250℃ is propelled and cylinder is allowed to move continuously so that all beans are evenly roasted and do not burn out. Roasting beans induces certain chemical reactions and releases different volatile aromatic compounds that are responsible for the rich flavour of coffee. Roasted beans are powdered and brewed for making coffee.
Can you imagine coffee in some other colour than brown?
In the menu of a coffee bar we come across a number of coffee drinks like Espresso, Latte, Cappuccino, Americano, Mocha etc. Most of them are all the espresso-based drinks differing in proportions of espresso, milk (or cream) and foam. Recent days we have another one too into the menu. Can you imagine coffee in another colour? Green coffee is the new member mostly preferred by fitness lovers. Green coffees are simple hot drink made from unroasted raw coffee beans. Because the beans are unroasted, green coffee carries a different herbal flavour making it more different from regular coffee.The green coffee bean powder is brewed in water and served hot after it is filtered. Since it is not prepared in milk or cream it is cholesterol and fat free.
Chlorogenic acid aiding in weight loss
While other coffees are popular across the globe since quite olden times, green coffee has just started its way in grab attention among fitness beverages. It was first launched as an effective weight loss supplement. However, there was quite longer debate about its effectiveness. Chlorogenic acid (CGA) is the active ingredient aiding weight loss. Chlorogenic acid though naturally present in coffee beans, most of it is lost during the roasting process. Since green coffee is un-roasted and raw beans chlorogenic acid is higher. So, it was launched as weight loss supplement basing on its high CGA content.
Does it really have that“miraculous” effect as claimed during its launch?
Green coffee was stated as a miraculous weight loss supplement during its launch into market. There was big health controversy over its weight loss effects.After conducting mice and human trails, researchers learnt that weight loss effects of chlorogenic acid in mice on high fat diet were almost negligible and that those obese mice were likely to develop Type-2 diabetes.
Other studies of green coffee in human fed with low fat, healthy diet and regular physical exercise showed quite good results. However, researchers believe studies are still needed in order to believe Green coffee as a weight loss supplement. More of human based trials having large group data are needed before a perfect conclusion is drawn.
Thermogenic action of green coffee
Basically, human beings are endotherms. They maintain steady internal temperatures around 37℃ for the internal enzymes to be functionally active. When its hot outside produces sweat to cool off while it shivers during fall of external temperatures. Shivering is special muscular exertion that kicks off chilling experience. In this way endotherms remain less dependent on external temperatures by producing their own heat.
The internal heat generation consumes energy and since it is heat production its termed as thermogenesis. Fitness experts believe thermogenesis as one good way of burning calories. Thermogenesis is again exercise induced and botanical thermogenesis (based on herbal diets). Exercise induced thermogenesis causes more energy expenditure, increased protein synthesis thereby increased muscle mass. Botanical thermogenic agents facilitate a greater calorie utilization and provide the body with more some other benefits too.
Ephedrine, p-synephrine, caffeine, chlorogenic acid, capsaicin, capsiate, green tea, forskolin, carotenoids, isoflavones and flavonoids are herbal based natural thermogenic agents.
One thing to be kept in mind is that thermogenic foods only guarantee an increase in calorie burning but the effect can only be long lasting if the calories burning by physical activity accompanies it. Afterall supplements can only add some more sweat to workouts. But sole dependence on supplements never ensures good weight loss results.
Though the thermogenic action of natural agents is slow the effects of their consumption are wider. Caffeine is rich in coffee beans and is well known CNS stimulant. Caffeine is known as competitive inhibitor for enzyme phosphodiesterase. So, it inhibits the breakdown of 3′5′-cAMP. cAMP is a well-known signalling molecule of CNS.
Caffeine has adenosine receptor blockage activity. Basically, adenosine suppresses lipolysis so the activity of caffeine in blocking the receptor has an effect as increased lipolysis. This makes free fatty acids more available for digestion.
Also, caffeine induces the activation of adenylate cyclase (enzyme for cAMP production). Cyclic AMP produces a series of pharmacological effects like vasodilation, smooth muscle contraction, diuresis, increase in blood pressure etc. All of these are energy consuming processes.
Chlorogenic acid biochemically as a fat burner
Though coffeeis world popular beverage, knowledge about non-caffeine constituents is little. Chlorogenic acid is one among many non-caffeine constituents having biochemical importance. Chlorogenic acid is naturally present in coffee beans. During the roasting process, chlorogenic acid is converted to some other forms and roasted coffee has low CGA levels.
Chlorogenic acid chemically falls under polyphenols and is an ester of caffeic acid with quinic acid. Chlorogenic acid is whole set of hydroxy cinnamic esters of quinic acid with caffeoyl-, feruloyl-, dicaffeoyl- and coumaroyl- groups. Of all the isomers in each alkyl subgroups 5-caffeoylquinic acid is most common isomer of chlorogenic acid and is present in green coffee beans.
Chlorogenic acid reduces the fat absorption from diet and reduce the stored fat levels. Researchers studied this action of chlorogenic acid directly and also as a constituent of green coffee and it showed to reduce carbohydrate absorption which helps in maintaining low blood sugar levels.Chlorogenic acid has thermogenic effects and green coffee is a combination of chlorogenic acid along with antioxidants that increase fatty acid availability in blood. This prevents unnecessary fat accumulation.
Chlorogenic acid is an inhibitor of enzyme pancreatic lipase(hydrolyses the lipids in digestive tract). The enzyme is responsible for breaking the dietary triglycerides into simpler monoglycerides and free fatty acids. Since chlorogenic acid inhibits the pancreatic lipase activity in breaking the lipids therefore the fatty acid absorption through digestive tract is low.
Biochemically, chlorogenic acid in green coffee induces body fat loss. It acts as a physiological activator of peroxisome proliferator activated receptor alpha (PPAR-α). PPAR-α is mainly involved with free fatty acid oxidation in skeletal muscle and brown adipose tissue.
Caffeine in green coffee release the fatty acids from stored fats. Chlorogenic acid induces liver for extra secretion of bile for improved processing of fatty acids. This combined effect can aid in loss of stored fats. Fitness experts design a combination of thermogenic foods along with physical exercise for reducing the waist lines in physical fitness seekers.
Both these effects on metabolism might have been preventing weight gain when the subjects are on regular physical exercise.
However, depending only on supplements for weight loss is never a perfect solution. Following a perfect regimen in both diet and exercise aspects along with supplements can show better results. After all, “supplements” can only add the “extra elemental effects” when worked with necessities. There can be no short cuts for weight loss without perfect eye watch on diet and physical work out.
Apart from its positive effects on glucose and fat metabolism, chlorogenic acid is reported to have anti-inflammatory, anti-carcinogenic and anti-bacterial activities. Its anti-carcinogenic properties are credited for free radical scavenging activities.
Reactive oxygen species (ROS) are highly reactive metabolic products of oxidative steps in various cellular organelles. Mitochondrial electron transport chain, cellular NADPH oxidase, endoplasmic reticulum, activated phagocytes produce ROS. Under normal physiological conditions ROS function as signalling messengers. An excessive generation of ROS can have negative impact on the oxidative balance of cellular environment. ROS at greater levels pose damage to DNA, proteins and lipids. Neurodegenerative disorders like Alzheimer’s, Parkinson’s, Huntington’s disease, diabetes, several cancers and ageing are caused when ROS exceeds their permissible levels.
Chlorogenic acid acts as a metal chelator and helps in scavenging free radicals. It has an inhibitory action on lipid peroxidation and NADPH oxidase activity both of which have role in ROS reduction. However, these anti-carcinogenic activities of chlorogenic acid are confined to cellular studies. Comprehensive studies aiming on organ systems with both long term and short-term consumption are yet on the way. Chlorogenic acid as a constituent is still to be studied for better understanding as functional food.
However, no studies so far have proved a negative shade on chlorogenic acid. Its biochemical properties boosted its value. So, Green coffee can be a good choice of hot beverage if someone wants a new and a different try from the regular roasted coffee. It is available as green coffee beans as well as extract and the hot beverage is prepared by brewing it.
Roasted and Green coffee are pretty different though borne on same branch
- It tastes quite different and mild than roasted coffee and is more like a hot mug of herbal tea.
- Its origins from plants make it more likely to have anti-oxidant as well as anti-inflammatory effects.
- Caffeine is relatively low in green coffee beans compared to regular roasted coffee.
- Pushing back the weight loss aspects, green coffee has gained people attention for its distinct taste. Apart from chlorogenic acid Green coffee is also a source of caffeine but has some herbal flavour. After all both “Green and Brown” are from same branch. But there is big journey for turning from green to brown. Roasting changes the biochemical table of coffee beans.
Recommended dosage
Green coffee can be tried as fitness beverage as it has been proved that no possible harm is imposed on ingesting it. A maximum of 3 or 4 cups a day for a healthy adult can be recommended. Diabetics, pregnant women and persons with high blood pressure need physician consultation before deciding safer intake.
/Disclaimer: The information provided in this article is just for the information of General Health Supplements. Science Arena Does not claim any health benefits nor its authors in any form, all the data and information shown are based on the personal experience and reference health data taken from Health practitioner. [Not For Medicolegal Purpose]/
