After water, coffee is the most widely consumed beverage in the United States. According to a 2015 report cited by theSpecialty Coffee Association of America, “the retail value of the U.S. coffee market is estimated to be $48 million dollars.” A Gallup poll found that almost two-thirds of American adults report drinking at least one cup of coffee per day. Millions of people start their day with a cup of coffee, or two or three, and many continue to drink it throughout the day. While the effects of coffee are generally harmless or even beneficial, excessive coffee drinking does pose a number of risks.
How much coffee is too much?
The American Medical Association Council on Scientific Affairs states that average or moderate coffee consumption is about four 8 ounce cups of brewed or drip coffee per day. Ten 8 ounce cups of coffee per day is considered excessive and may be associated with health risks. Coffee is a complex beverage, containing over 1000 compounds, the most frequently studied of which is caffeine. Most of the negative effects of excessive coffee consumption are linked to the caffeine it contains.
How much caffeine is in coffee?
According to a USDA database, one 8 ounce cup of brewed coffee contains about 95 milligrams of caffeine. Research has found, however, that caffeine content of coffee can vary widely. In fact, an 8 ounce cup of coffee can have up to about 200 milligrams of caffeine in it. It is difficult to know exactly how much caffeine you will be getting when you order a cup of coffee. A particular variety of coffee, even purchased from the same coffee shop on different days, can have very different levels of caffeine. Considering that coffee is commonly served in cups considerably larger than 8 ounces (e.g., 12, 16 or even 20 oz), caffeine content can reach anywhere between 112 and 375 milligrams for one “cup” of coffee.
Dangers of excessive coffee drinking
While moderate coffee drinking has been associated with a variety of positive health effects, excessive coffee drinking can have negative effects. Anyone who has been a coffee drinker and has tried to quit “cold turkey” knows that the unpleasant effects of withdrawal can include headaches, fatigue, irritability and nervousness (1). While these effects are generally mild and resolve within a few days, they can make coffee-drinking a difficult habit to break.
Symptoms of caffeine withdrawal:
• Confused thinking
• Runny nose
• Muscle tension
• Muscle pains
• Flushed face
1. Excessive coffee drinking and the nervous system
The caffeine in coffee is a stimulant, which can increase our alertness and ability to concentrate on a task. In excessive amounts, however, it can lead to:
• fast heartbeat,
• upset stomach,
• muscle tremors,
• and insomnia.
A negative cycle can occur when people drink large amounts of coffee to help them stay awake during the day, but then are unable to sleep well at night, leading them to be tired again the next day and rely on coffee once again to get through the day. Given that quality sleep is crucial for healthy brain function, memory, and overall health, the negative effects of insomnia caused by overconsumption of caffeine should not be underestimated (3).
2. Excessive coffee drinking and bone health
Caffeinated beverages including coffee increase urinary excretion of calcium and other minerals. Calcium is essential for healthy, strong bones. If lost calcium is not replaced through calcium-rich foods or supplements, excessive coffee drinking can increase risk of weakened bones, osteoporosis, and fractures.
According to the National Osteoporosis Foundation…
“Drinking more than three cups of coffee every day may interfere with calcium absorption and cause bone loss.”
Older women, in particular, may not adequately replace calcium lost due to excess caffeine consumption. Researchers have found that women who drink the highest amounts of caffeinated coffee over their lifetimes have the lowest bone mineral densities, putting them at risk for fractures. In older women who do not drink milk, as little as two cups of coffee per day were associated with decreased bone density (5). However, among milk drinkers this association was not found.
3. Excessive coffee drinking and blood lipid levels
In addition to caffeine, coffee contains compounds called diterpene alcohols, which have been shown to increase serum lipid levels. A review of research found that coffee-drinking, particularly of unfiltered (boiled) coffee was associated with significantly higher total cholesterol, LDL-cholesterol and triglyceride levels (6). Those people who already had elevated cholesterol levels were more sensitive to the effects of coffee drinking. The diterpenes in coffee are extracted by hot water, but are retained by the paper filter when one is used. Therefore, coffee prepared using a filter method is not likely to raise lipid levels (7) and, in fact, may even decrease risk of heart disease (8).
Effects of diterpenes from unfiltered coffee:
• Increased total serum cholesterol
• Increased LDL-cholesterol
• Increased triglycerides
4. Coffee and pregnancy
Women who are pregnant are often advised to avoid or limit caffeine intake. The caffeine in coffee can cross the placenta and affect the baby’s heart rate. While more research is needed on the potential risks associated with caffeinated coffee consumption during pregnancy, some studies have shown higher caffeine consumption to be associated with lower birth weight. For women who do drink coffee, health care providers often recommend limiting total amount of caffeine during pregnancy to less than 200 milligrams per day, or about 16 ounces of coffee.
According to the International Food Information Council Foundation…
“Daily consumption of up to 300 mg/day (approximately two to three cups of coffee) has been shown to have no adverse effects on pregnancy.”
Choosing a healthy alternative to coffee
While light or moderate consumption of coffee is fine for most people, many healthy and satisfying alternatives to coffee are available. Whether you are looking to cut out caffeine or coffee completely, or just to cut down on the number of cups of coffee you drink each day, there are many great options to choose from.
Alternatives to Coffee:
• Decaffeinated coffee
• Green tea
• Black tea
• Healthy smoothies
• Healthy snacks
• Flavored water
• Unsweetened carbonated water
1. Decaffeinated Coffee
Decaffeinated coffee is a great choice for people who love coffee, but who don’t love the unpleasant effects that excessive coffee consumption can have. Since it looks and tastes the same as regular coffee, it can be an easy substitute. In addition, some research shows that decaffeinated coffee may have health benefits similar to regular coffee. Higher consumption of decaffeinated coffee may lower type 2 diabetes, for example, as well as overall risk of death (9,10).
2. Green and black teas
While most teas still contain some caffeine (about 47 milligrams per cup of black tea and 29 milligrams per cup of green tea), it is far less than the average cup of coffee (11,12). In addition, tea may have beneficial effects on health, including possible roles in preventing cancer and heart disease (13). A hot mug of black, green or herbal tea could be a great replacement to that fifth or sixth cup of coffee!
3. Matcha Tea
Matcha tea has been used for centuries in China and Japan, and has more recently become popular in the United States. Matcha is a finely ground powder made from shade-grown tea leaves, with a more intense sweetness and deeper flavor than that of standard grades of green tea. Although traditionally prepared by mixing only with hot water, other uses include as an addition to smoothies or iced teas.
Kombucha is a fermented, sweetened drink made with green or black tea, sugar, bacteria and yeast. While it can be brewed at home, conditions must be completely sterile to avoid contamination and illness. An easier alternative is to purchase ready-made kombucha, which comes in a variety of flavors. While some people drink kombucha as a health aid, clear health benefits have not been shown.
5. Smoothies and other snacks
If you are one of those people who feel like they hit an afternoon slump, and rely on coffee for a late-afternoon pick-me-up, you may want to reconsider. What you may actually be experiencing is a dip in blood sugar after your lunchtime meal has been digested, rather than actual tiredness. In that case, a healthy snack or a smoothie could be exactly what you need. Go for a snack that has carbohydrate and protein (think string cheese and an apple, or a banana with peanut butter), or for a healthy smoothie. Combine plain yogurt with your favorite frozen fruit, and a handful of spinach or kale for that extra nutritional boost.
Healthy smoothie ingredients:
• Plain, unsweetened non-fat yogurt
• Frozen pineapple, berries, mangoes
• Spinach or kale
• Protein powder
• Powdered peanut butter
• Chia or flax seed
While your smoothie blender is sometimes out of reach and you may have forgotten to pick up kombucha from the store, water is nearly always available. Excessive coffee drinking can cause dehydration, which in turn can lead to fatigue. Most often, water should be your number one choice for rehydrating. Up the excitement factor and the nutrition by adding some lemon, lime or orange zest to your water, along with sliced fruit. Or try a glass of water with mint and cucumber. Unsweetened carbonated water is another great choice and is available in many flavors.