Caffeine is one of the most studied food and beverage ingredients, with centuries of safe use

Safety

More than 140 regulatory agencies throughout the world, including the U.S. Food and Drug Administration (FDA), the European Union Scientific Committee on Food – SCF (replaced in 2003 by the European Food Safety Authority – EFSA), and Food Standards Australia New Zealand (FSANZ), consider the appropriate use of caffeine in food to be safe. While caffeine can be a mild stimulant depending on the amount consumed, intakes as high as 400-450 mg per day have been noted by Health Canada as being without any adverse health effects for adults, excluding adult women who are pregnant or lactating. For most adults, this is considered to be equivalent to three to five cups of regular coffee per day.

Metabolism

Caffeine does not accumulate in the body over the course of time and is normally excreted within several hours of consumption. This varies among individuals but healthy adults usually excrete caffeine within 3 to 4 hours. Individual sensitivity to caffeine varies greatly from person to person and depends on such factors as the frequency and amount of regular intake, body weight, and physical condition. Some people can consume caffeinated products late in the evening without appreciable impact on their ability to sleep, while others find even a small amount of caffeine keeps them awake. Consuming too much caffeine can cause restlessness, poor sleep, anxiety and irritability in some people, as well as headaches, abnormal heart rhythms or other problems. However, most people tend to find their own acceptable level of daily caffeine consumption, and those who experience unwanted effects tend to limit their caffeine consumption.

Health professionals often recommend that certain sub-populations, such as children, pregnant and nursing women and those sensitive to caffeine, limit or avoid caffeine consumption. Pregnancy and aging may affect an individual’s sensitivity to caffeine. It is recommended that pregnant or nursing women, or women trying to become pregnant, follow their healthcare providers’ advice regarding caffeine intake.

Caffeine & Health

Moderate caffeine intake, equivalent to two to three cups of coffee or five to six cans of caffeinated sparkling beverages for adults, has not been linked with any health problem. Heavy consumers who abruptly stop consuming caffeine can experience headaches and other mild symptoms. In recent years, the term “addiction” has been used to refer to certain foods of enjoyment, prompting speculation as to whether foods and beverages containing caffeine are addictive. Caffeine is considered a mild stimulant, but according to the World Health Organization, it is wrong to compare caffeine intake to drug addiction. Scientific studies show that people can reduce or completely eliminate their caffeine intake without the serious psychological or physical problems that result from a true addiction.

Caffeine in moderation has been shown to have a positive effect on both physical and mental performance. Studies have found that individuals who consume sufficient caffeine may experience temporary improvements in memory and reasoning ability. Recent research also suggests that caffeine in sufficient amounts may have a positive impact on athletic performance and endurance.

There is no evidence that caffeine causes children to become hyperactive or to develop attention deficit disorder. However, it is advised that children consume caffeine in moderation appropriate to their size.

The impact of caffeine on bone health is a commonly held concern. However, research shows that caffeine and caffeinated beverages like colas have a minimal impact on calcium kinetics, and that the lifestyle behaviors most critical to bone health are consuming a nutritionally complete diet, including adequate calcium and vitamin D, and getting regular weight bearing exercise. The International Osteoporosis Foundation (IOF) also says moderate caffeine intake appears to have no detrimental effects on bone health as long as calcium intake is adequate. Learn more.

Because caffeine is a mild diuretic, questions have also been raised about the impact of caffeinated beverages on hydration status. However, the U.S. Institute of Medicine states that all beverages, including those with caffeine, contribute to hydration. Learn more.

An in-depth review by the U.S. FDA  in 1987 found no evidence that the use of caffeine in soft drinks would harm health.

Caffeine Content of Common Foods and Beverages

Beverages* Milligrams of Caffeine – per 8 fl. oz. (240 ml)
Coca-Cola 23 mg
Diet Coke, Coca-Cola light® or Coca-Cola Zero 23 to 31 mg
Barq’s Root Beer 16 mg
Sprite 0 mg
Fanta Orange 0 mg
Coffee, Dripped Brew 65 to 120 mg (85 mg typical)
Energy Drinks 70 to 85 mg (depending on the brand)
Brewed Tea (U.S.) 0 to 90 mg (40 mg typical)
Foods Milligrams of Caffeine – per 1 oz (30 mg)
Cocoa Powder 3 to 32 mg (6 mg typical)
Milk Chocolate 1 to 15 mg (6 mg typical)
Dark Chocolate 5 to 35 mg (20 mg typical)

*The Coca-Cola Company offers a wide range of beverages, both with and without caffeine, including caffeine-free versions of Coca-Cola and Diet Coke, or Coca-Cola light®