WARNING!
This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.
By Dr. Mercola
Coffee has been identified over recent years as having several health benefits, including lowering the risks of some of the most serious and common diseases, such as stroke, Type 2 diabetes and heart disease. Scientists haven't always been able to pinpoint the mechanisms for the beneficial and protective aspects of coffee, but new information has come to light, according to a study published in PLOS Biology.1
Conducted by researchers with Heinrich Heine University and the IUF-Leibniz Research Institute for Environmental Medicine in Dusseldorf, Germany, the study revealed a "new mode of action for coffee" — an intriguing concept for the millions of people worldwide for whom coffee is a prerequisite for their days (and nights). Health benefits include improved mitochondrial and respiration-dependent processes in your cardiovascular system.
The mechanism providing the benefits, surprisingly, is caffeine, a celebrated stimulant. Consumed in specific doses, caffeine increases the cyclin-dependent kinase inhibitor 1B (CDKN1B)/p27 (previously known as a cell cycle inhibitor), a regulatory protein localized within mitochondria, known as your cells' energy powerhouses. The study authors wrote:
"The migratory capacity of endothelial cells, which need intact mitochondria, is completely dependent on mitochondrial p27. Mitochondrial p27 improves mitochondrial membrane potential, increases adenosine triphosphate (ATP) content, and is required for the promigratory effect of caffeine."2
Earlier research by the scientists showed that for maximum benefit, the concentration of caffeine is very specific: A minimum of four cups of coffee (or four espresso shots) was determined to be the amount to promote the migration of the regulatory protein into your mitochondria, enhancing the function of endothelial cells lining blood vessel interiors, while simultaneously protecting your cardiovascular cells from damage. According to Science Daily:
"Here, they showed that a protein called p27, known mainly as an inhibitor of the cell cycle, was present in mitochondria in the major cell types of the heart. In these cells, mitochondrial p27 promoted migration of endothelial cells, protected heart muscle cells from cell death, and triggered the conversion of fibroblasts into cells containing contractile fibers — all crucial for repair of heart muscle after myocardial infarction.
They found that caffeine induced the movement of p27 into mitochondria, setting off this beneficial chain of events, and did so at a concentration that is reached in humans by drinking four cups of coffee. Caffeine was protective against heart damage in pre-diabetic, obese mice, and in aged mice."3
Specific Amounts of Caffeine and the Roles of P27
Lead study authors Judith Haendeler and Joachim Altschmied note that caffeine's "mode of action" promotes not only protection, but heart muscle repair due to the movement of p27. Only after consuming that four cups — or 32 ounces — is endothelial "translocation" into mitochondria induced. As Newsweek puts it, "Regulatory proteins bind to specific parts of the DNA and play a role in how genes are expressed. This involves helping to protect cardiovascular cells from damage."4
Endothelial cells in blood vessels play many critical roles in maintaining your health, especially vascular function. It's closely related to the mitochondria because these are where cells turn the proteins, fats and sugars you eat into forms of chemical energy your body needs for optimal function and health. As the optimal concentration of caffeine promotes cell migration and protects your heart, Digital Journal observes:
"It is important to note, however, that this effect of caffeine has only been tested out in pre-diabetic, obese mice, and in aged mice. The same effects may not necessarily occur in humans and further study will be required."5
In addition, the researchers noted, "p27 protects heart muscle cells from cell death and is necessary for the conversion of fibroblasts into mechanically strong, contractile myofibroblasts, a process critical after myocardial infarction [heart attack]."6 As Science News explains, "Normally, p27 is found in the nucleus of cells, where it helps control when cells divide. Its energy-boosting role in the mitochondria wasn't known before."7
Mitochondrial p27 also increases adenosine triphosphate (ATP) content, the study notes, and protects cardiomyocytes (cardiac muscle cells) against apoptosis, or programmed cell death. Haendeler said she believes the study can lead to better approaches for protecting heart muscle from damage and could even change the conversation regarding the viability of coffee consumption or caffeine specifically as an additional dietary factor for elderly individuals.
If in fact mitochondrial p27 could be used as a potential therapeutic strategy for preventing cardiovascular disease, it could potentially lengthen your health span — the length of time a person stays healthy. One of the upshots for the study and several that have gone before is, as Forbes succinctly discloses, it's the reason why caffeine/coffee can be helpful for an individual after suffering a heart attack, and "… may even be protective for people at higher risk of heart disease. This will no doubt be music to some people's ears."8
Coffee Consumption and Cancer Protection
Previous studies on the potential benefits of coffee consumption show it to be protective against four of the most prevalent killer diseases in the U.S. — heart disease, cancer, diabetes and stroke. In particular, multiple studies over several years show drinking coffee imparts benefits related to cancer protection. Here are three of numerous examples:
- Among people with advanced colon cancer, four or more daily cups of coffee lowered the risk of cancer recurrence or death by 52 percent compared to those who drank no coffee at all.9
- A meta-analysis in 2007 reported that an increase in consumption of two cups of coffee per day was associated with a 43 percent reduced risk of liver cancer.10
- Another meta-analysis involving 59 studies revealed an increase in consumption of one cup of coffee per day was associated with a 3 percent reduced risk of cancers.11
What is it about coffee that extends these kinds of benefits? One answer is powerful antioxidants called polyphenols. Antioxidants are nature's way of providing your cells with adequate defense against attack by reactive oxygen species (ROS) or free radicals, a type of a highly reactive metabolite that is naturally produced by your body as a result of normal metabolism and energy production.
In fact, Americans get more antioxidants from drinking coffee than any other dietary source, with researchers noting "nothing else even comes close."12 That research was presented at an annual meeting of the American Chemical Society (the world's largest scientific society) way back in 2005. Examples of the antioxidants in coffee include significant amounts of hydrocinnamic acid and polyphenols.
Haendeler is also aware there will be people who start drinking more coffee based on her team's research, but she cautions they should also engage in other heart protective activities such as exercising and eating right. Otherwise, she says, it probably won't do people much good.
Drinking too much coffee may also have an opposite effect of driving too much p27 into mitochondria, destroying them, which could exacerbate health problems. She added, "Don't [just] take caffeine pills, stop eating a healthy diet and exercising and be a couch potato."13
If You Take Caffeine Pills, You Miss Out on All the Polyphenols
In the case of how coffee benefits your heart, it appears that caffeine may play a role but that doesn't discount the benefits of the polyphenols contained in coffee (which are absent in caffeine pills). It's interesting that in 2013, researchers observed in the Journal of the American College of Cardiology that, "Coffee is a complex beverage containing hundreds of biologically active compounds."14
After water, coffee and tea are the most popular beverages in the world. They contain caffeine, yes, but they're also loaded with antioxidant polyphenols, which are major conveyors of nutritional benefits. The potent polyphenolic compounds in coffee may help reduce the risk of stroke and diabetes, and improve glucose levels and blood pressure, among many other things. For its part, drinking coffee is linked to a reduced risk of premature death; particularly death related to cardiovascular trouble.15
Still, even if you're not a coffee drinker, you can easily boost your antioxidant intake by eating fresh produce. Vegetables and fruits, particularly berries, are ideal sources of antioxidants. And if you do drink coffee, getting your antioxidants from a varied diet is still the best way to get a wide variety of plant-based nutrients, some of which can't be found anywhere else.
Choosing the Best (Read: Healthiest) Coffee to Drink
For the best flavor and optimal health from the polyphenols and other health beneficial compounds in coffee, choose organic, shade-grown coffee. It's available at retail markets or order it online. You'll also want to purchase coffee in whole bean form and grind it yourself to prevent rancidity, as pre-ground coffee may be rancid by the time you drink it.
Studies vary on whether drinking decaffeinated coffee offers the same benefits as the caffeinated variety, but if you drink decaf, be sure the decaffeination process doesn't involve chemicals, such as Direct Process, which uses the chemical methyl chloride to strip the caffeine from coffee beans, which PubChem, an open chemistry database, lists as a possible carcinogen.16 When it comes to coffee consumption (and to some extent every other type of food or beverage) it's crucial to make sure the coffee beans are:
- Pure and unadulterated
- Not sprayed with pesticides or herbicides, chemicals or synthetic fertilizers, which both contaminate the product and negate the benefits
- Not irrigated using contaminated water
- Not from genetically engineered sources
- Enjoyed au naturel; drink it black or with MCT (medium-chain triglycerides) oil, which is a good fat that provides even more advantages for your health, as opposed to with sugar or pasteurized cream