Symptoms can range from mild to severe that are dependent on the amount of caffeine consumed daily. Tests are still being done to get a better understanding of the effects that occur to someone when they become dependent on different forms of caffeine to make it through the day. Adults
Caffeine is consumed by many each day and from this a dependence is formed. For the most part caffeine consumption is safe, but consuming over 400 mg of caffeine has shown adverse physiological and psychological effects; especially in people that have pre-existing conditions. When adults form a dependence on caffeine, it can cause a range of health problems such as headaches, insomnia, dizziness, cardiac issues, hypertension and others. When an adult is dependent on this substance, they must consume a certain amount of caffeine every day to avoid these effects. Pregnancy
If pregnant, it is recommended not to consume over 200 mg of caffeine a day (depending on size of person). If a pregnant female consumes high levels of caffeine, it can result in low birth weights due to loss of blood flow to the placenta which could lead to an increase health problems later in that childs life. It can also result in premature labor, reduced fertility, and other reproductive issues. If a female is depended on an excessive amount of caffeine to get them through the day, it is recommended to talk to their healthcare provider to either eliminate the dependency of caffeine or to become less dependent on it.
Children and Teenagers
It is not recommended for children under the age of 18 to consume several caffeinated drinks according to the American Academy of Pediatrics (AAP). If they were to consume caffeine it is recommended to follow some guidelines so they do not consume too much throughout the day. If they do, they can become dependent on caffeine and without it can suffer many different side effects. These include increase of heart rate and blood pressure, sleep disturbance, mood swings, and acidic problems. Long lasting problems on childrens nervous system and cardiovascular system are currently unknown and studies are still being conducted on it. Tolerance
Tolerance levels regarding caffeine typically vary from person to person. Caffeine tolerance occurs when the stimulatory effects of caffeine decrease over time due to regular consumption. According to H.P. Ammon from the National Library of Medicine, caffeine tolerance occurs when the body responds to an intake of caffeine through the up-regulation of adenosine-receptors. References


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