Coffee Health Benefits
Roasted Coffee Beans
A Brief History of Coffee
Coffee is believed to have originated in Ethiopia.
The first evidence of coffee drinking is from the 15th century in Yemen.
By the 16th century, coffee had reached the rest of the Middle East, South India, Persia, Turkey, and Northern Africa.
Coffee eventually made its way to the Balkans, Italy, and the rest of Europe, followed by Indonesia and then America. In each of these regions, coffee evolved beyond being merely a beverage; it became an integral part of the culture, accompanied by unique rituals and traditions related to its consumption.
How Many Coffee Species Are There?
More than 130 species of the Coffea genus have been identified, but only two species dominate the global market.
Arabica
The Arabica coffee plant Coffea arabica accounts for almost two-thirds of the world's coffee production.
Robusta
Also known as Coffee canephora, this species was cultivated after an outbreak of leaf rust nearly wiped out coffee production in Asia. Robusta coffee is generally considered to be of lower quality compared to Arabica. The flavor of Robusta coffee beans is often described as having a burnt rubber taste. These beans are most commonly used in blends and instant coffee products. Additionally, Robusta contains about twice the caffeine of Arabica beans.
Coffee fruit is also referred to as coffee cherry.
Coffee Consumption
Coffee, a beverage that transcends borders, is the most widely consumed drink in the world, second only to water.
An estimated 2.25 billion cups of coffee are consumed each day worldwide.
Depending on your location, you'll discover a rich tapestry of coffee cultures, each with its unique preparation and serving methods.
Global Coffee Culture
America: Filter coffee, Starbucks. It's clear that the coffee in America often leaves much to be desired when the best option seems to be Starbucks. I spent more time than I'd like to admit searching for a drinkable coffee in the States. If I remember correctly, the best coffee we found on the West Coast was either in Portland, Oregon, or Boise, Idaho.
Australia: Serves flat white, long black, cappuccino, ristretto, and latte. I may be biased, but I genuinely believe that Australia makes the best coffee in the world!
Austria: Kapuziner (espresso and whipped cream)
China: Yuangyang (coffee, black tea, sweetened condensed milk)
France: Cafe, cafe creme, cafe au lait, French press
Greece: Frappe, frappuccino, freddo espresso
Indonesia: Kopi terbalik, kopi joss (coffee with burning charcoal), kopui luwak (coffee bean collected from the poo of the civet. kopi turbruk (coffee grounds, water)
Ireland: Irish coffee (Irish whiskey, coffee, sugar, cream)
Italy: Espresso, espressino (espresso, steamed milk, cocoa), cafe latte (espresso, steamed milk, milk foam), cappuccino, ristretto, cafe americano, macchiato, barbajada (espresso, sweetened milk, cocoa)
Malaysia: Ipoh white coffee (coffee beans, margarine, condensed milk)
Mexico: Cafe de Olla (ground coffee, cinnamon-infused sweetened water, cocoa beans, anise, clove, or orange zest)
Portugal: Cafe com cheirinho
Saudi Arabia: Arabic coffee
Senegal: Cafe Touba (coffee, guinea pepper, cloves)
South Korea: Dalgona (instant coffee, sugar, water, whipped)
Spain: Cortano, cafe bombon (coffee and condensed milk), cafe del tiempo (coffee, ice, lemon). cafe con miel (espresso, steamed milk, honey, cinnamon)
Turkey: Turk Kahvesi (coffee, water, sugar) brought to a boil in a cezve.
Vietnam: Vietnamese Yoghurt coffee, ca phe trung (Vietnamese coffee, egg yolks, condensed milk)
Caffeine Absorption and Effects
Caffeine is quickly absorbed primarily in the small intestine, with some absorption occurring in the stomach. This rapid absorption is why you often feel the effects of caffeine shortly after drinking coffee. Most (99%) of caffeine is absorbed within ~45 minutes.
The peak level of caffeine in the body occurs 1-2 hours after coffee consumption.
The half-life of caffeine is 2.5-5 hours, depending on several factors. Smoking, genetics, health status, oral contraceptives, and pregnancy are some of the factors that can influence caffeine's half-life.
The half-life of something refers to the amount of time that it takes for the concentration of a substance to decrease to half the starting dose in the body.
Coffee can also impact the absorption and excretion of some vitamins and minerals and the metabolism of some medications.
Coffees Bioactive Compounds
Coffee contains over 1,000 different bioactive compounds.
Caffeine: The most abundant and well-known chemical in coffee is caffeine, which is responsible for coffee's pungent aroma and bitterness and the component responsible for keeping you awake. Caffeine also has antioxidant, pro-inflammatory, and anti-diabetic properties.
Chlorogenic Acids: They are also responsible for coffee's bitterness and have antioxidant benefits.
Caffeic Acid: Has potential benefits, including antioxidant, anti-inflammatory, and anti-cancer properties.
Trigonelline: Has anti-inflammatory, anti-cancer, and neuroprotective benefits.
Kahweol and Cafestol: Tryptophan has various biological effects on the body, including altering mood, cognition, sleep, aggressiveness, vomiting, and other physiological processes. Consuming coffee has been shown to increase the availability of the neurotransmitter 5-hydroxytryptamine (5-HTP), a precursor to serotonin production.
Melanoidins: It has antioxidant, anti-inflammatory, and anti-hypertensive benefits.
Diterpenes: It has antioxidant, anti-inflammatory, and anti-cancer benefits, and it is also pro-cholesterol.
Niacin (Vitamin B3): It helps in the metabolism of carbohydrates, fats, and protein. It improves cholesterol levels and blood circulation, enhances the immune system, helps maintain the nervous system, and improves psychological well-being.
Coffee and the Gastrointestinal System
For those of you who incorporate coffee into your morning routine to help with bowel movements, this might not surprise you. Coffee can stimulate the large intestine, prompting movement as quickly as four minutes after consumption, similar to the effects of eating cereal. This is due to the presence of bioactive compounds in coffee, such as caffeine and chlorogenic acids, which stimulate the release of certain hormones and increase the motility of the digestive system. Interestingly, decaffeinated coffee has a comparable impact, with noticeable effects between four and thirty minutes post-consumption.
One study compared coffee intake to water intake and the time until the first poo after a caesarean section. The coffee group did their first poo in a shorter amount of time compared to the water group.
Another study compared coffee, warm water, and nicotine use on rectal tone and visceral sensitivity. Rectal tone was increased by 45% 30 minutes after coffee intake and 30% 30 minutes after water intake. The rectal tone change was not significant in the nicotine or placebo groups.
Another study compared coffee and water in patients experiencing postoperative ileus after abdominal surgery. A postoperative ileus typically occurs after abdominal surgery when the intestines have been manipulated. An ileus means the normal intestinal muscle function that contracts and pushes food through the digestive system has temporarily stopped. When the usual pushing of food through the digestive system stops, food isn't going anywhere, and this causes bloating, vomiting, constipation, cramping, and loss of appetite. When this occurs, an individual will require feeding with liquid food through a nasogastric tube that passes through the nose and into the stomach. In this study, the coffee group had their nasogastric tube removed quicker than the water group and had a reduced length of stay at the hospital.
The evidence for coffee causing or increasing reflux symptoms is inconclusive. Some studies say coffee consumption is associated with reflux symptoms, others do not, and another says that decaffeinated versus caffeinated coffee reduces symptoms.
Coffee, Awakeness, and Sleepiness
Have you ever wondered why caffeine makes you feel more awake and can keep you from sleeping?
A molecule called adenosine plays a role in sleep-wake regulation. Adenosine levels continually rise while we are awake, promoting sleep by reducing the areas of the brain that keep us awake. The longer you stay awake, the higher the adenosine concentration is, and the more you want to sleep. Adenosine levels then decrease while we are asleep.
Caffeine blocks adenosine receptors, which keeps adenosine levels low; this promotes wakefulness.
Chronic caffeine users may experience changes in the adenosine system due to the metabolite paraxanthine, which can affect sleep. Studies using rat and mouse models have shown that chronic caffeine consumption leads to an increase in the number of adenosine receptors.
Coffee and Anxiety
Research shows that disturbed sleep and anxiety are seen in people chronically consuming 5 cups (>500mg caffeine) of coffee per day.
In people who have anxiety disorders, consuming 10mg/kg of caffeine can cause symptoms of anxiety and panic attacks due to plasma caffeine levels.
Healthy people with variations in the ADORA2A gene have an increased risk of anxiety symptoms when consuming regular amounts of caffeine.
Health Benefits of Coffee
Type 2 Diabetes:
Consuming 2-3 cups of caffeinated and decaffeinated coffee each day can lower the risk of type 2 diabetes. Coffee is also believed to decrease glucose absorption.
Cardiovascular Disease Risk:
Three cups per day lowers the risk of high blood pressure, cardiovascular disease, stroke, heart failure, death after a heart attack, and death by any cause.
Bone Health:
Men, three cups per day lowers your risk of osteoporotic fractures.
Ladies, drinking one cup a day increases the risk of osteoporotic fractures.
Depression:
Lowered risk of depression by 24% with 3-4 cups versus none.
Kidney Health:
Dose-dependent lowered risk of chronic kidney disease, kidney stones, and gout.
Alzheimer’s Disease:
Conflicting results may be a lower risk of Alzheimer's disease with the highest intake versus no intake.
Liver Disease:
Dose-dependent lowered risk of chronic liver disease-related conditions (fibrosis, cirrhosis, non-alcoholic fatty liver disease), liver cancer, pancreatitis, and gallstone disease.
Gut Health:
Increases Bifidobacterium, which has a prebiotic effect in animal studies, and improves gut motility (the movement of food through the digestive system). In people with irritable bowel syndrome, symptoms worsened with coffee intake.
All-cause mortality:
Lowered risk of death by any cause.
How Much Coffee Should I Be Drinking?
3-4 cups per day for optimal health benefits. 1 cup is equal to ~100mg of caffeine.
Who Should Limit Coffee?
Pregnant Individuals: Caffeine and its metabolites pass freely across the placenta to the foetus. Pregnant individuals should consume no more than 200mg of caffeine per day. High caffeine intake (>300mg/day) during pregnancy increases the risk of pregnancy loss, low birth weight, and first and second-trimester preterm birth.
Osteoporosis: Large amounts of coffee consumption have been shown to increase urinary excretion of calcium. In postmenopausal women, calcium is an essential nutrient due to the loss of oestrogen. It plays a role in bone formation and the prevention of bone breakdown.
Digestive system: Coffee consumption has been associated with an increase in symptoms of irritable bowel syndrome. The evidence for inflammatory bowel disease is not solid. In one study, coffee intake decreased the risk of ulcerative colitis but not Crohn's disease. A meta-analysis showed that coffee intake may be protective for individuals with ulcerative colitis and Crohn's disease, although not significantly. A reported two-thirds of people with inflammatory bowel disease avoided coffee due to gastrointestinal symptoms.
High Blood Cholesterol: Coffee has a short-term effect of increasing blood fats, including total cholesterol, LDL (bad) cholesterol, and triglycerides.
References
Sloots, C. E. J., Felt-Bersma, R. J. F., West, R. L., & Kuipers, E. J. (2005). Stimulation of defecation: Effects of coffee use and nicotine on rectal tone and visceral sensitivity. Scandinavian Journal of Gastroenterology, 40(7), 808–813. https://doi.org/10.1080/00365520510015872