By Jason Jensen, NMD.
Coffee Consumption Affecting Health
Two biologically active compounds found in coffee, caffeine and phenolic acids, have potent antioxidants properties that can affect glucose metabolism and reproductive hormone levels.
Polyphenols, particularly flavonoids and phenolic acids, are greatly abundant in tea and coffee and contribute largely to their flavor and beneficial health properties. Rutgers University Department of Food Science researchers reviewed the polyphenol chemistry of tea and coffee, specifically their stability and scavenging (antioxidant) ability of reactive oxygen species (ROS) and reactive carbonyl species (RCS). Both ROS and RCS are considered toxic to human cells. Chlorogenic acid is the main polyphenol in coffee, where the second "B" ring is the preferred site for antioxidation.
- Brain - neuroprotective
- Cancer - lowering prostate cancer risks
- Heart & Blood - decreases LDL-cholesterol
- Inflammation - lowers urate levels
- Skin - limits UV age spots
High Coffee Consumption Risk Linked To Cardiovascular Disease
Researchers from the Department of Biostatistics and Epidemiology, University of South Carolina, Columbia, evaluated the link between coffee consumption and mortality. Base-line data was gathered from 43,727 participants from a medical examination, including blood analysis, blood pressure, electrocardiography, and an exercise test.
During the study's 17-year follow-up, 32% of deaths where found due to cardiovascular disease. Coffee intake was "positively" associated with increased mortality in men who drank 28 cups or more of coffee per week.
When researchers adjusted for age, they found younger men and women (less than 55 years of age), showed a "significant" association between high coffee consumption, and higher mortality rates. Younger women appear to be more affected by high coffee comsumption than men, based on comsuming 28 cups, or more, per week:
- 1.21 - Hazard ratio for men over 55
- 1.56 - Hazard ratio for men under 55
- 2.13 - Hazard ratio for women under 55
Based on their findings, researchers suggest that younger people avoid heavy coffee consumption, averaging 4 or more cups per day, and that their data should be compared to future studies of other populations. Their work appeared in Mayo Clinic Proceedings. PMID: 23953850
Roasted Coffees Are More Neuroprotective Than Green Coffees
Green coffee beans decreased brain cell lifespan 22%, compared to doubling brain cell lifespan (203%) with dark roasted coffee beans.
Coffee is one the most popular beverages in the world, having been consumed for thousands of years for its alluring flavor and health benefits. This widely consumed beverage is rich in many bioactive components including polyphenols that have antioxidant properties Oxidative stress is believed to cause many neurodegenerative diseases leading to age-related cognitive decline, but can be alleviated by antioxidants. In a 2009 study published in the Journal of Agricultural Food Chemistry, researchers tested regular and decaffeinated samples of both roasted and green coffee all showing high hydrophilic antioxidant activity when taken internally. This lipophilic antioxidant activity is 30 times higher on average in roasted coffee more; than green coffee samples. In primary neuronal cell cultures, pretreatment with green and roasted coffees (regular and decaffeinated) protected against subsequent H2O2-induced oxidative stress and improved overall brain cell survival.
All coffee bean extracts inhibited ERK1/2 activation, indicating a potential attenuating effect in stress-induced brain cell death. Interestingly, only roasted coffee extracts inhibited JNK activation evidencing a distinctive neuroprotective benefit. Analysis of coffee phenolic compounds revealed that roasted coffees contained high levels of chlorogenic acid lactones (CGLs); and a significant correlation between CGLs and neuroprotective efficacy was observed. In conclusion, this study demonstrated roasted coffees are high in lipophilic antioxidants and CGL can protect neuronal cells against oxidative stress, and may do so by modulation of the ERK1/2 and JNK signaling pathways.
Caffeine Slows Brain Cell Death
A study from Germany's, University of Tübingen, published in the journal Cell Physiology Biochemisty, 2008, shows how caffeine inhibits red blood (erythrocyte) cell death.
Eryptosis, the death of red blood cells, is characterized by cell shrinkage and by cell membrane scrambling with weakened phosphatidylserine exposure at the cells’ surface. Eryptosis is triggered by several stress conditions including isotonic cell shrinkage (Cl(-) removal) and energy depletion (glucose removal). Both dehydration and glucose depletion effectively increase calcium concentration in blood cells. Phosphatidylserine-exposing blood cells are cleared from circulating blood. Enhanced blood cell loss thus leads to anemia. Under controlled conditions, eryptosis affected less than 5% of the blood cells and was not significantly modified by the presence of caffeine (50-500 microM). In conclusion, it was found that caffeine inhibits calcium entry following glucose depletion thus counteracting blood cell loss during isotonic cell shrinkage and energy depletion.
Six Cups of Coffee Per Day Limits Prostate Cancer
47,911 men participated in a 20 year follow-up study of health professionals, that tracked regular and decaffeinated coffee consumption every 4 years from 1986 to 2006. At the end of the study, 5035 patients were identified to as having prostate cancer, 642 of those had terminal prostate cancers. The average coffee intake in 1986 was 1.9 cups per day. However, men who consumed six or more cups per day had a 40% lower risk for overall prostate cancer compared with nondrinkers. Fatal prostate cancer rates were similar for regular and decaffeinated coffee drinkers, which suggests that coffee's health effects are partially related to non-caffeine components. PMID:21586702
Coffee Lowers Cholesterol
Chlorogenic substances are responsible for a decrease in plasma LDL cholesterol observed in some populations, notably Scandinavia and Italy (Urgert et al., 1996,1997; Urgert and Katan, 1997)
In a 2004 study, it was discovered that regular coffee ingestion may favorably affect cardiovascular risk status by modestly reducing LDL oxidation susceptibility and decreasing LDL-cholesterol PMID:14972021
Heart Health Conflicting Evidence
A Netherlands study showed that drinking four or more cups of coffee a day can raise homocysteine levels in blood. Chlorogenic acid appears to increase homocysteine levels. High homocysteine levels are a known risk factor for heart disease. Researchers found that people who drank 4 or more cups of coffee a day had 11 percent higher levels of homocysteine than non coffee drinkers. Unlike caffeine, chlorogenic acid can not be readily filtered.
Regular coffee consumption is often viewed as unhealthy. However, habitual coffee drinking is not associated with increased risk of cardiovascular diseases or premature mortality among diabetic women. PMID:19266179
Lowering the Risk of Gout
Coffee and vitamin C supplementation are considered as preventive measures, lowering urate levels, reducing the risk of gout. PMID:20035225
Limiting Age Spots
Researchers demonstrate how coffee protects human skin from photoaging. Polyphenols, chlorogenic acids contained in coffee contribute to decreased hyperpigmentation of age spots. Polyphenol consumption was associated with low facial pigmented spots in Japanese middle-aged females. PMID:25041334
Author Jason Jensen is a licensed naturopathic medical physician in the state of Arizona.
Hold the Dairy? A major dairy milk protein, β-Lactoglobulin, combines with polyphenols (found in tea, coffee, and cocoa) reduces antioxidant activity in the body. Researchers from the University of Belgrade published their coffee research in Food Chemistry, Feb. 2013. PMID: 23194522
Plant Remedies Research
Collection of peer-reviewed and published academic papers.