Coffee Consumption and Health: The Final Word – Part 1
Written on November 13, 2011 at 7:44 pm, by Eric Cressey
I’m excited to present to you an awesome guest post on coffee consumption from Brian St. Pierre. I learned a lot reading this two-part series over, and I’m sure you will, too!
Coffee is the second most popular drink in the world, trailing only water (and debatably, tea). As you all know, caffeine is a key component of coffee and is a compound of great debate. It is the world’s most consumed psychoactive drug, with 90% of North American adults consuming caffeine daily. However, is this such a bad thing?
Many health advocates would try to convince you to give up coffee and possibly even caffeine altogether. However new research has certainly raised the question, should we actually give up our beloved Cup o’ Joe?
Does Metabolism Matter?
There is a lot of conflicting research on coffee consumption, and it seems to be because people have different clearance rates for caffeine. On one hand, you have the “slow” metabolizers of caffeine: people who are adversely affected by caffeine, get the jitters, and are wired for up to nine hours. Then, there are those who simply have an increase in energy and alertness that wears off within a few hours; they are considered “fast” metabolizers of caffeine.
This seems to be a defining difference in whether or not coffee will help you or hurt you, as those who are slow metabolizers may be at an increased risk for a non-fatal heart attack, while the fast metabolizers may not.
If you are a slow metabolizer of caffeine and coffee, steer clear. It’s not for everybody, and it is not for you. In your case, it can do more harm than good, and this may explain why coffee consumption has been associated with:
- Increased risk of miscarriage
- Interference of normal sleeping patterns
- Increased PMS symptoms
- Increased blood pressure, even in people without hypertension
- Non-fatal myocardial infarction
Fortunately, this seems to be a minority of the population. For those lucky enough to be fast metabolizers, there is good news – and lots of it.
Why Coffee Rules
Coffee has more antioxidants than dark chocolate or tea, and may make up as much as 50-70% of the total antioxidant intake for the average American!
A recent study found that men who drank the most coffee (6 or more cups per day) were nearly 60% less likely to develop advanced prostate cancer than non-coffee drinkers.
In fact, at least six studies have found that regular coffee drinkers have up to an 80% decreased risk for developing Parkinson’s.
In addition, other research has shown that when compared to non-coffee drinkers, people who regularly consume two or more cups per day may have a 25% decreased risk of colon cancer, up to an 80% decreased risk for cirrhosis, a 35% decreased risk of type 2 diabetes, and up to a 50% decreased risk for gallstones!
In terms of the gallbladder protection, it was only seen in people who drank caffeinated coffee. So, if you drink decaf, it’s not doing much for the gallbladder.
The final verdict on coffee and cancer is that coffee consumption is associated with a lower overall risk of cancer. Period. Specifically, coffee consumption has shown to be associated with a lower risk or oral, esophageal, pharyngeal, breast (in post-menopausal women), liver, colon, and aggressive prostate cancer. Sounds good to me!
Beyond the health benefits, there are many noted mental and physical performance benefits as well. Caffeine has been shown to reduce the rate of perceived exertion, so it doesn’t feel like you are working as hard as you really are. In addition, people who regularly drink coffee have been found to have better performance on tests of reaction time, verbal memory, and visuo-spatial reasoning.
Taking it a step further, another study found that elderly women over the age of 80 performed significantly better on tests of cognitive function if they had regularly consumed coffee over the course of their lifetimes.
In addition, many people think of coffee as increasing their risk for cardiovascular disease (CVD), but the reality is that coffee consumption has been found to moderately reduce the risk of dying from CVD. Another study, done in Japan, followed 77,000 individuals between the ages of 40 and 79. Researchers found that caffeine and coffee consumption were also associated with a reduced risk of dying from cardiovascular disease.
One other coffee/caffeine myth is the idea of dehydration. It is widely believed that caffeine-containing beverages like coffee and tea cause the body to expel more fluid than they provide, but does the research actually back this up?
Nope.
A recent review of 10 studies found that consuming up to 550mg of caffeine per day does not cause fluid-electrolyte imbalances in athletes and fitness enthusiasts. Another review the following year found that consuming caffeine-containing beverages as part of a normal lifestyle does not lead to fluid loss in excess of the volume of fluid ingested, nor is it associated with poor hydration status. Myth busted.
That seems like an awful lot of awesome with respect to coffee consumption, but does it continue? Check back soon for part 2 to find out!
Related Posts
Healthy Food Options: Why You Should Never Take Nutrition Advice from Your Government
Metabolic Cooking: Making It Easy to Eat Clean
About the Author
 Brian St. Pierre is a Certified Sports Nutritionist (CISSN) and a Certified Strength and Conditioning Specialist (CSCS). He received his degree in Food Science and Human Nutrition with a focus in Human Nutrition and Dietetics from the University of Maine, and he is currently pursuing his Master’s degree in Human Nutrition and Dietetics from the same institution. He was the Nutritionist and a Strength and Conditioning Coach at Cressey Performance in Hudson, MA for three years. He is also the author of the Show and Go Nutrition Guide, the accompanying nutrition manual to Eric Cressey’s Show and Go Training System.
With his passion for seeing his clients succeed, Brian is able to use his knowledge, experience, and energy to create highly effective training and nutrition programs for clients of any age and background. For more information, check out his website.
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References
Cornelis MC, et al. Coffee, CYP1A2 Genotype, and Risk of Myocardial Infarction. JAMA. 2006;295(10):1135-1141
Wisborg K, et al. Maternal consumption of coffee during pregnancy and stillbirth and infant death in first year of life: prospective study. BMJ. 2003 326 (7386): 420.
Richelle M, et al. Comparison of the Antioxidant Activity of Commonly Consumed Polyphenolic Beverages (Coffee, Cocoa, and Tea) Prepared per Cup Serving. J. Agric. Food Chem., 2001, 49 (7), pp 3438–3442
Leitzmann WF, et al. A prospective study of coffee consumption and the risk of symptomatic gallstone disease in men. JAMA. 1999 281:2106-12
Leitzmann MF, et al. Coffee intake is associated with lower risk of symptomatic gallstone disease in women. Gastroenterology. 2002 Dec;123(6):1823-30
Webster Ross G, et al. Association of Coffee and Caffeine Intake With the Risk of Parkinson Disease. JAMA. May 24, 2000, 283:20
Hancock DB, et al. Smoking, Caffeine, and Nonsteroidal Anti-inflammatory Drugs in Families With Parkinson Disease. Arch Neurol. 2007;64(4):576-580.
Klatsky AL, et al. Coffee, Cirrhosis, and Transaminase Enzymes. Arch Intern Med. 2006;166:1190-1195.
van Dam RM, Hu FB. Coffee consumption and risk of type 2 diabetes: a systematic review. JAMA. 2005 Jul 6;294(1):97-104.
Tavani, A, et al. Coffee and tea intake and risk of oral, pharyngeal and esophageal cancer. Oral Oncol. 2003 39 (7): 695-700.
Ganmaa D, Willett WC, Li TY, et al. Coffee, tea, caffeine and risk of breast cancer: a 22-year follow-up. Int J Cancer 2008 122 (9): 2071-6.
Inoue M, Yoshimi I, Sobue T, Tsugane S. Influence of Coffee Drinking on Subsequent Risk of Hepatocellular Carcinoma: A Prospective Study in Japan. JNCI Journal of the National Cancer Institute 97 (4): 293-300
Nkondjock A. Coffee consumption and the risk of cancer: an overview. Cancer Lett. 2009 May 18;277(2):121-5.
Arab L. Epidemiologic evidence on coffee and cancer. Nutr Cancer. 2010;62(3):271-83.
Somoza V, et al. Activity-Guided Identification of a Chemopreventive Compound in Coffee Beverage Using in Vitro and in Vivo Techniques. J Agric Food Chem. 2003 51 (23), pp 6861–6869
American Association for Cancer Research Frontiers in Cancer Prevention Research Conference, Houston, Dec. 6-8, 2009.
Jarvis MJ. Does caffeine intake enhance absolute levels of cognitive performance? Psychopharmacology. 2 December 2005, 110:1-2, 45-52.
Johnson-Kozlow M, et al. Coffee Consumption and Cognitive Function among Older Adults. Am J Epidemiol 2002; 156:842-850
Lopez-Garcia E, et al. The Relationship of Coffee Consumption with Mortality. Annals of Internal Medicine 2008 Jun 17;148(12):904-14.
Koizumi A, Mineharu Y, Wada Y, Iso H et al. Coffee, green tea, black tea and oolong tea consumption and risk of mortality from cardiovascular disease in Japanese men and women. Journal of Epidemiology and Community Health 2011 65: 230-240.
Armstrong LE. Caffeine, body fluid-electrolyte balance, and exercise performance. Int J Sport Nutr Exer Metab. 2002 Jun;12(2):189-206.
Maughan RJ, Griffin J. Caffeine ingestion and fluid balance: a review. J Hum Nutr Diet. 2003 16(6):411–420.
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November 13th, 2011 at 8:13 pm
Phew! I’ll drink to that…
November 13th, 2011 at 10:41 pm
Brian,
As a new parent, like yourself, this is great news! My coffee consumption has sky-rocketed since the days of sleeping are long gone. Good stuff, my man.
November 14th, 2011 at 12:32 am
Good article, I’m looking forward to part 2 as well. I love the taste of coffee.
One thing I try to watch out for in regards to caffeine intake is people under any type of chronic stress (a lot of people). Since coffee increases catecholamine levels, this can be destructive to someone, in the context of already elevated stress hormones. Too much adrenal stimulation could contribute to other problems.
In the studies you cite, do you know if the researchers controlled for a “healthy-subject effect” in coffee drinkers? Just curious, at the very least these results show that coffee intake is benign.
Tyler
November 14th, 2011 at 1:21 am
How great is it to read this while drinking my morning cup of coffe? 😀
November 14th, 2011 at 7:33 am
McB, Matt G, & Jacob,
Thanks and enjoy!
Tyler,
I have heard that theory kicked around, and in theory I could see excessive coffee/caffeine consumption being a problem, but do you have any actual data on habitual coffee intake ever leading to adrenal issues? I think it can be important to keep in mind that acute response does not necessarily lead to long-term results/consequences.
Off the top of my head I believe many did, but not sure if all. There are over 500 papers on coffee and cancer alone. In terms of coffee consumption though, its not like it is a food that people drink for health purposes. Healthy and unhealthy people alike drink coffee, and it is often associated with smoking, so a healthy user bias is less likely to be an issue. I think green tea would be a beverage where teasing that apart would yield more significant data, as people do tend to drink that for health purposes.
Brian
November 14th, 2011 at 10:03 am
Great article! I love coffee and enjoy one or two cups per day. My problem is when I don’t have coffee, the withdrawal symptoms are nuts. My headaches are so severe that I’m incapacitated for up to a day. So is the answer staying on coffee permanently? Or is something that causes a reaction like that not a good idea. I really struggle with this one. Thanks
November 14th, 2011 at 1:25 pm
First coffee enthusiast!
Trialing creatine on myself and I can’t have my beloved coffee 🙁 🙁
November 14th, 2011 at 4:32 pm
Just something glaring to me in the post is that you stated that coffee drinkers are at lower risk for a variety of of cancers and type II diabetes. Although, 90% of Americans drink coffee daily. So why is the incidence of cancer and type II diabetes on the rise? To me it would seem that the health benefit of coffee mainly comes in the form of antioxidants. And most Americans although they drink coffee don’t exercise or eat healthy. Therefore, the benefits do not out weight the risks of that persons unhealthy lifestyle. Oxidative stress has been demonstrated as the main culprit in both cancer and type II diabetes. Therefore, if people are consuming antioxidants in a different form they will still be receiving the same health benefits that have been shown in coffee as long as they also eat healthy and exercise. Just some food for thought coming from a non-coffee drinker!!
November 14th, 2011 at 11:41 pm
Fascinating! I just got a 23andme profile back and it said I was a slow metabolizer, which I would’ve expected. Caffeine keeps me up until 2 or 3AM, even if it’s just one cup of coffee in the morning! I will definitely avoid it from now on.
November 15th, 2011 at 12:02 am
What a great article, and I don’t even drink coffee!
It would be real interesting to have the same type of article/resource on energy drinks and diet sodas with caffeine just to have as a basis of comparison.
November 15th, 2011 at 12:29 am
@ Stephen Thomas, PhD, ATC: I have long heard that some caffeine intake will reduce Type II Diabetes incidence, but I’ve always suspected that it was due to the fact that is raised the metabolism & ‘forced’ the body to workout due to the higher basal metabolic rate.
I’ve never considered coffee a major source of anti-oxidants. (Did I miss something??)
@ Brian St. Pierre — I wanted to share with you a ‘bad’ reaction I had to caffeine yesterday, since it could save someone’s life:
On occasion, I will mix a 5-Hour Energy into a ‘small’ (approx. 8 oz) Red Bull, and both have 80mg caffeine, so I would get 160mg caffeine plus misc. B-vitamin, Taurine, Choline, etc.)
That’s usually not a problem, but twice in my life, but this Sunday, after a stressful day, I got the 2 energy drinks to heal back up, & about 4 hours later, I had racing heartbeat & nervousness, meaning I’d od’ed. Now, i’m only 120 to 125 lbs in BW, which might have meant I had a lower carrying capacity than my heavier neighbours.
This all I say to help someone else a bad reaction like myself.
November 15th, 2011 at 12:32 am
I love my coffee as well but have recently been following a new style of eating following the principals of Michel Montignac (first guy in the GI diet world) and he talks about the hyperinsulinic effect of coffee consumption and states that this is an effect that one should avoid. The premise of the GI based protocols is to reduce the sugar and insulin levels in our system by consuming low GI foods as well as avoiding foods that lead to an increase in insulin secretion, one of which is coffee. Is there research or evidence that contradicts this information? I have personally had a tremendous amount of success with this style of eating (dropped 30 pounds in a healthy way in less than 3 months)but would love to be able to enjoy my java.
November 15th, 2011 at 6:33 am
I think it’s important to note that this article is highlighting the benefits of COFFEE, not a venti mocha triple pump estrogen latte with extra whip.
November 15th, 2011 at 7:00 am
Good information. In regards to “antioxidants” I would note two things:
1.) Coffee (if not organic) contains some of highest pesticide residuals alongside dark chocolate.
2.) We produce SO many free radicals (especially those that exercise too much) that you would have to drink coffee all day to reap the benefits of decreased lipid peroxidation and oxidative stress.
If you are a “slow metabolizer” you can get around consuming caffeine by adding raw milk, raw sugar, and sipping small amounts throughout the day to reap the benefits that greatly exceed what was discussed here!
I await part 2!
November 15th, 2011 at 7:41 am
Hey great article call me old fashion but I
still feal too much of anthing isnt good.
November 15th, 2011 at 8:30 am
It certainly seems like there was a lot of research done on this topic. Seeing positives isn’t the only thing to look at. It is still important to look at the negative effects of coffee. Anything that has addictive properties is something to be concerned with. If people get headaches and can’t function when they don’t have their coffee that is a problem.
November 15th, 2011 at 9:04 am
I live for my morning cup of coffee. There isn’t a day I go without it. Like many, I can experience some serious withdrawal symptoms if I don’t have it…namely headaches.
But I’m also in agreement with many that it’s good in moderation…as most things in life.
November 15th, 2011 at 9:49 am
Soooooo, what you’re saying is Spike counts, right?
Kidding. Awesome post B. Looking forward to part II!
November 15th, 2011 at 11:17 am
Question: How many of these health benefits are due to caffiene itself and how many are due to compounds in the coffee beans?
November 15th, 2011 at 11:43 am
I went to a runner’s injury prevention workshop hosted by the NYU hospital for joint diseases last year and the nutritionist there linked coffe/caffeine (>200mg) consumption with sudden death in runners. The running event being anything longer than an10K and the caffiene consumption being prior to the run. Thoughts?
November 15th, 2011 at 11:57 am
FINALLY!!!! I have science to back up the reason I don’t drink coffee! I am a slow metabolizer of caffeine! I’ve never been able to consume the stuff without getting the jitters, etc. I can’t even consume chocolate without experiencing negative effects! Thank you for a very informative article!
November 15th, 2011 at 12:02 pm
Finally!!! I have science to back up the reason I don’t drink coffee! I am a slow metabolizer of caffeine! I’ve never been able to consume the stuff without experiencing negative effects such as an increased heart rate, jitters, etc. Thank you for a very informative article!
November 15th, 2011 at 1:00 pm
Would the benefits noted include the use of caffinated pre-workout energy drinks, or are the benefits directly related to coffee consumption?
November 15th, 2011 at 2:06 pm
Steve,
If it were me I would probably wean off, caffeine may not be appropriate for you with that type of reaction. Maybe try tea instead and see how you respond.
Blaine,
There is no reason to avoid coffee when taking creatine.
Stephen,
Actually the incidence of cancer on a per capita basis is on the decline – http://apps.nccd.cdc.gov/uscs/. Eating well and exercising are obviously beneficial components of a healthy lifestyle, but all foods have unique compounds, and in the case of plants phytochemicals/antioxidants. Certain benefits from coffee are only specifically from coffee (as you will really see in part 2), and these benefits can not, or at least have not, been replicated in any other way or with any other food. It is important to remember that antioxidants is a broad term covering thousands of compounds. In addition it is also important to remember that we don’t eat antioxidants, we eat food, and in this case, coffee, that provide the benefits.
Flash,
Why choose synthetic man-made “energy drinks” when you could have simply chosen something with documented health benefits? That would have been a perfect time for coffee(or tea)!
Tony,
A little coffee is most certainly not going to diminish your weight loss efforts. In reality the GI is not a reliable tool for weight loss purposes, but that is another discussion for another day. In addition acute insulin response is also not correlated with weight gain – it is a normal physiological response to eating!
Nick,
The roasting process of making coffee tends to degrade the vast majority of the pesticide residue. While I am usually an advocate for organic if one can afford it, with coffee I feel it is a personal choice, not a personal health choice.
Lee,
I agree, but there is not a whole lot of negative research on coffee. Some, but not much. I touched on what I found.
Tony,
Hahaha, only in your dreams.
Brian
November 16th, 2011 at 9:41 am
Great as always! Big greetz from berlin germany!
November 16th, 2011 at 10:58 am
Awesome article. I am a fan of the Java!
November 16th, 2011 at 5:54 pm
Brian,
I have read that DECAF does not have any of the benefits of regular coffee, I see in your article it mentions DECAF does not have the benefit for the gall bladder. Does DECAF have the other benefits or is that unknown?
November 16th, 2011 at 5:55 pm
Hmmmm,
It goes back to the individual as you had mentioned Brian. I don’t wanna sound like a deusherstein because I believe caffeine can be a great aid to the human body, which those with their shit together should absolutely take advantage of.
However, Most individuals I come across are not apart of athletics or in the fitness field and are addicted to caffeine and their adrenal glands are fried. Caffeine is the exact opposite of what I would offer as sound advice for someone already jacked hormonally and is running a thousand miles an hour mentally and hormonally. They can’t sleep, aren’t happy, are fat, and typically have man boobs/saddlebags.
I am assuming Part II would address this?
Or WHY NOT. let’s all just have a SPIKE party and call it a day.
December 9th, 2012 at 8:40 am
Not so fast.
As somebody well aware that any scientist who doesn’t secure grants is considered a loser by his departement and his school, we are all entitled to wonder who paid for all the studies listed in this article. We have reached a point in our society where we MUST have access to who pays to have anything being said about anything before we take it into account. For example, there is NOT studies on nuts ( wallnut, etc) out there not financed by the industry. I strongly suspect this is the same for coffee. If you drink coffee, keep it two two cups a day. If you don’t, don’t start to drink it to be healthy.
December 9th, 2012 at 10:11 am
It’s seems one aspe t that a missing is the sugar consumption that oftens goes with coffee… Lets see 2 cups per day with 2 – 3 teaspoons of sugar works out to around 1200-1500 teaspoons of sugar per year. Why don’t you take a picture of that and discuss any unintended consequences that come from that… Drinking coffee rarely happens in a vacumn…. By the way I have never had a cup of coffee i my 20 years of training.
December 9th, 2012 at 11:33 am
I’ll echo Yael’s comment that 23andMe DNA profiling includes whether you’re a fast or slow caffeine metabolizer.
(I’m fast)
December 9th, 2012 at 1:39 pm
With regard to the effects of caffeine on individuals we also need to consider the health of the phase 1 and phase 2 detox pathways of the liver. Those with a strong phase 1 but weak phase 2 may actually be able to “handle” caffeine a little easier – that is, not be affected as much.
As is often the case, we really need to focus on the effects on the individual rather due to what is happening in their body rather than making blanket statements on one food, exercise, etc. I think Brian has started this particularly well so far – I look forward to part 2!
December 9th, 2012 at 2:23 pm
If coffee is such a fantastic beverage why then do so many die of cancer? Do I miss something?
December 9th, 2012 at 3:19 pm
espresso based drinks made with freshly roasted beans ground just before extraction affect me far less than drip or plunge style coffee. Any noted research on the composition of coffee of different styles of extraction/bean age/roasting style ? I understand espresso to have less caffeine and darker roasts to have less also as they’ve been exposed to heat longer, perhaps that is the only reason?
December 10th, 2012 at 7:25 am
As a female committed coffee imbiber I am relieved to read that I am not at risk of prostate cancer! LOL
December 10th, 2012 at 8:54 pm
Rainer,
That’s quite possibly the silliest thing I’ve ever heard.
December 11th, 2012 at 7:26 pm
Glad we could help, Barbara!
December 28th, 2012 at 8:04 pm
Coffee has tars and requires the hard working liver to work harder and longer to get rid of toxic tar.
Anyone who drinks even a small amount of coffee has put a handicap on himself.
Bad aspect of coffee is its effects on the digestion of many people, causing an increase in stomach acidity with burning in the pit of the stomach. It should definitely not be used by anyone who has an ulcer.
Coffee is not a natural beverage for man, it’s an Arabic drink that spread to Europe in the 17th century. Like cigarettes, its consumption has increased markedly since the beginning of the 20th Century, parallel with increase in heart attacks, ulcers, lung cancers and other common ailments.
The U.S.A consumes more than 70 % of the world’s coffee crop.
FREE YOURSELF FROM THE VICIOUS COFFEE HABIT
Coffee contain the powerful drug caffeine, therefore if your central nervous system demands caffeine would you not say “I am addicted to the drug caffeine?” you can free yourself from this deadly habit .But you must be strong during the withdrawal period . Yes you will be nervous and jittery, when your central nervous system is addicted to drug this always happen, but in less than a week you will freed yourself from drug addiction. You will be free again. Coffee will no longer be your master.
That goes for decaffeinated coffees .they have some of drugs removed, but the “dope “is steel there
No.1 COFFEE RELIEVES FATIGUE
Coffee hides fatigue, it paralyses the fatigue center and makes a person think he is rested when in fact, he is really tired
No-2 COFFEE INCREASE ONE’s ABILITY TO PERFORM
The very opposite is true
No-3 COFFEE AIDS CONCENTRATION
The only people whose concentration is helped by coffee are those whose powers of concentration have been damaged by its use. This action is similar to that which occurs with the whisky drinker who must have “another” to steady he’s nerves
No 4 COFFEE DOESN’T DRAW UPON BODY’S PHYSICAL RESERVES
Nothing could be further from the truth. When one is fatigued, one needs rest, not a power drug stimulant like caffeine. If we drink a cup of coffee we no longer feel fatigued but we need the rest just the same .If we go on working we expend energy which the body cannot afford
AdChoices
No- 5 COFFEE BENEFICIALLY INCREASES HEART ACTION
Coffee excites the heart and leads to quickening of the pulse ,just as a whip excites the horse .The effects of a coffee are not spectacular like a “pot” or LSD or even alcohol .it is subtle drug and all more dangerous because of this.
One can easily be lulled into a sense a of false security and fail to realize how harmful coffee is until a great deal of damage has been done by consuming too many cups in short period of time .
Coffee contains no really natural nutrition t o assist the body to higher standard of health.
It contains no vitamins, minerals, enzymes or nutrients.
It has tars which can foul up the hard working liver. it puts a strain on the kidneys as coffee contains uric acid.
In other words coffee can do your body absolutely no good and may do it a great deal of harm.
I have noticed people who have consumed coffee for many years that they have definite tremble in the hands, many heavy coffee drinkers have the out and out shakes
Read the fact and stop the habit
If you drink two cups of ordinary coffee every day you are loading your body witha drug called caffeine .Now if you went to drug store and asked the pharmacist to sell you the same amount of caffeine that you drank in your two cups of coffee, he would painterly say ” you need a prescription for a strong drug like a caffeine” Yet you can purchase coffee which is full of drug without a prescription.
An average cup of coffee contains from 70 to 150 milligrams of caffeine, which means that two cups of coffee can give you a pretty good jolt. How much, depend how strong the coffee is and how strong the drinker is .A dose of Coffee 150 To 250 milligrams stimulates the cortex of the brain .In other words, it turns one on . However delicate muscular coordination may be hampered by this dose.
No stimulant is good and its free use always results in depleted vitality, coffee is heart stimulant .It forces the heart to work harder than it is expected to and heavy coffee drinkers often have much higher heart rates than they do after they stop drinking coffee.
Some studies suggest that drinking five to six cups of coffee a day is associated with an increased rate of heart attacks