What's the Scoop on Coffee?

Discover coffee varieties, what you should know about drinking it, what the studies say on coffee and health, and current recommendations for consumption.
What's the Scoop on Coffee? - Articles

Updated: August 14, 2017

What's the Scoop on Coffee?

What is Coffee?

Coffee typically refers to the drink made from the roasted beans of a coffee tree. The two main coffee trees used in the commercial industry are Coffea arabica and Coffea canephora. Coffea arabica represents about 70 percent of the world's coffee production and it tends to be higher in price and lower in caffeine. The other most common type, Coffea canephora, makes up 30 percent of the world's market and is used mainly for blends and instant coffees. It has a more distinctive taste than arabica and around 50 to 60 percent more caffeine. Roasting the beans brings out the aroma and flavor and readies them to be ground and brewed. There are a variety of ways to prepare and serve coffee. A typical "cup" of coffee is considered to be from 6 to 8 ounces. The table on below shows the size, ounce amount, and caffeine content for different preparation methods of coffee.

Coffee can also be served "decaffeinated" (i.e., without the "energy" ingredient, caffeine) while keeping the taste and smell at their original levels. Four methods of decaffeinating coffee exist today: indirect-solvent, direct-solvent, Swiss water process, and the carbon dioxide process. Indirect and direct solvent processes use the FDA approved chemicals methylene chloride or ethyl chloride. The Swiss water process uses the natural way, with water, and the carbon dioxide process uses carbon dioxide to remove the caffeine from the coffee beans. Decaffeinated coffee still contains 2 to 4 milligrams of caffeine in an 8-ounce cup.

Type of CoffeeSize (ounces)Caffeine content (mg)
Brewed895-200
Brewed single-serve varieties875-150
Espresso, restaurant-style145-75
Instant827-173
Specialty drink (latte or mocha)863-175

What should you know about drinking coffee?

Although coffee creations may involve the addition of many ingredients such as milk, sugar, and syrups, this fact sheet will focus on the "undressed" form of this beverage. Research shows that when used appropriately, coffee can be a safe, enjoyable, and even beneficial brew.

While coffee is a complex plant with many different features, one of its active ingredients (famous for making you active) is caffeine. Drinking coffee, particularly because of its caffeine content, may be of concern for some health conditions or situations. However, despite potential concerns, studies show that drinking 1 to 5 cups of coffee per day may prove beneficial for your health and does not cause increased risk for death. Chlorogenic acid and other antioxidant substances may be the active ingredients in coffee associated with lower rates of heart disease, diabetes, and certain cancers. Other substances in coffee, including kahweol, cafestol, lignans, and even caffeine, may lower the risk of certain cancers. The exact mechanisms of coffee to produce its health benefits remain mostly unknown. Although it is not necessarily recommended that everyone switch from their Earl Grey tea to a cup of java (coffee), some studies have found that coffee may provide some benefit.

What the Studies Say

ConditionCommentsRecommendations
PregnancyCaffeine can pass from mom to baby. Because of potential impact of caffeine, lower caffeine/caffeinated coffee intake is advised to reduce risk of miscarriage or problems in the baby's development.No more than 3 cups of coffee per day.
Bone density/ osteoporosisConsuming greater than 4 cups or 400 mg of coffee may be linked to a decrease in the density of bones; however, there is lack of strong evidence that coffee is to blame, but instead may be from not drinking enough calcium-rich beverages, such as milk.Limit to 2 to 3 cups per day, but not in place of calcium-rich beverages (e.g., milk).
DiabetesPeople with diabetes who have uncontrolled sugar levels may experience even more difficulty controlling blood sugar if consuming caffeinated coffee. Drinking caffeinated or decaffeinated coffee may lower risk for type 2 diabetes.If having difficulty controlling blood sugar, switch to decaffeinated coffee, which can be beneficial for diabetes.
Heart healthIf someone is not used to drinking caffeine and consuming 2 to 3 cups or more of caffeinated coffee a day, it may lead to increased blood pressure.If having difficulty controlling blood pressure, switch to decaffeinated coffee.
Heart healthPeople who drank coffee had a somewhat lower risk of death from cardiovascular disease than those who rarely drank it. Conservative consumption (1-3 cups of coffee per day) may decrease risk of heart attack.Limit caffeinated coffee to around 2 cups per day.
Brain healthDrinking coffee may improve brain health and lower risk for depression and rate of brain function decline.
CancerConsuming coffee may lower risk for certain types of cancer, such as liver, endometrial, aggressive prostate, and estrogen-negative breast cancer.
Liver healthCoffee drinking may improve liver health and protect against liver cancer.
Parkinson's diseaseCoffee drinking may decrease risk for Parkinson's disease.

Examine Your Choices

Special health considerationsWhat I currently drinkWhat I can change
Diabetes3 sugar-sweetened caffeinated coffee cups per dayUnsweetened or sugar-free sweetener, 1 cup caffeinated, 2 cups decaffeinated
Osteoporosis4 cups black, caffeinated coffee per dayAdd milk/milk alternative to 1 cup or drink separately
Trouble sleeping3 cups caffeinated coffee per dayAfter 2 p.m., drink decaffeinated

Current Recommendations

Currently, no U.S. Dietary Guidelines exist for the exact amount each person should or should not be drinking. For the casual enjoyer of this brew, a general guideline is to reduce the amount if experiencing signs of drinking too much, such as tremors, sleeping problems, feeling stressed, increased heart rate, or feeling uncomfortable.

Additional Tips

Specialty coffee-based drinks are common, but they can be high in sugar, fat, and calories. For those who are not black-coffee purists, these can be enjoyed as a healthier treat by choosing low-fat milk options, sugar-free syrups, or smaller portion sizes. If you are concerned about how much caffeine or how many calories you are consuming, fill your coffee mug up with water and then pour into a liquid measuring cup to see how many ounces it holds. Most hold 16-20 ounces or more, which is 2 or more cups of coffee. To see if drinking coffee may be enjoyable and beneficial for your lifestyle and health needs, try making and experimenting with your own coffee drinks at home. It will also be cheaper!

Vanilla Cafe au Lait

Ingredients

  • ½ cup milk (1%, soy, almond)
  • ¼ tsp sugar-free vanilla syrup
  • ½ cup caffeinated or decaffeinated coffee

Directions

  1. Brew coffee
  2. Heat milk and add sugar-free vanilla syrup
  3. Add milk to coffee and enjoy!

Sources

American Institute for Cancer Research, "AICR's Foods That Fight Cancer: Coffee," Sept. 19, 2013, www.aicr.org/ foods-that-fight-cancer/ coffee.html (accessed 6/26/2015).

Bailey, R. L., and L. Arab, "Nutritional prevention of cognitive decline," Adv. Nutr. 3 (2012) : 732-33.

Coffee Confidential, "Decaffeination 101: Four ways to decaffeinate coffee," (accessed 6/20/2015).

Harvard Health Publications, "Harvard Health Letter: What is it about coffee?" January 1, 2012, (accessed 6/26/2015).

Higdon, J. V., and B. Frei, "Coffee and health: A review of recent human research," Crit Rev Food Sci Nutr. 46, no. 2 (2006): 101-23, (accessed 6/9/2015).

Mayo Clinic, "Diseases and Conditions: How does caffeine affect blood pressure?" (accessed 6/9/2015).

Mayo Clinic, "Healthy Lifestyle: Caffeine content for coffee, tea, soda and more," (accessed 6/10/2015).

Mayo Clinic, "Healthy Lifestyle: Is coffee good or bad for me?" (accessed 6/9/2015).

National Coffee Association, "What is coffee?" (accessed 6/10/2015).

The Nutrition Source, "Ask the Expert: Coffee and health," February 23, 2015, (accessed 6/9/2015).

"Scientific Report of the 2015 Dietary Guidelines Advisory Committee," February 2015, (accessed 6/10/2015).

Prepared by Kelsey Cantor, nutrition, diet, health, and food safety intern, and Lynn James, senior extension educator in nutrition, diet, health, and food safety.

Instructors

Nutrition research and education Diabetes education Child overweight prevention Food Safety education Food Preservation

More by Lynn James, M.S., R.D., L.D.N.