Caffeine Sensitivity: Symptoms and Causes
After water, the most consumed beverages of many people are coffee and black tea, which contain certain amounts of caffeine. In addition, cola and energy drinks are among the drinks that contain caffeine and are frequently consumed.
Caffeine is a stimulant that affects the central nervous system. Although it has benefits for human health, there are also harms of excessive intake.
Caffeine can also cause sensitivity due to its stimulating effect. Caffeine sensitivity varies from person to person. While some people do not feel uncomfortable despite drinking 4-5 cups of coffee a day, others may experience symptoms such as insomnia and tension when they drink only a single cup of coffee.
There is no test that can measure caffeine sensitivity, but many people fall into the following 3 groups in terms of caffeine sensitivity.
Normally sensitive people
Most people are normally sensitive to caffeine. People in this group can take up to 400 milligrams of caffeine a day without experiencing any side effects.
Less sensitive people
About 10% of people are in this group. These individuals are not genetically affected by high caffeine intake. Even late in the day, they can consume caffeine-containing drinks in large amounts and do not encounter a problem such as not being able to sleep.
Hypersensitive people
People in this group can only tolerate very small amounts of caffeine. The genetic characteristics of people who are hypersensitive to caffeine may cause this, and the ability of their liver to metabolize caffeine may be insufficient.
Apart from these 3 groups, there are also people who are allergic to caffeine. The immune system of people with a caffeine allergy mistakenly perceives caffeine as an enemy or invader and fights against it by producing antibodies.
Caffeine sensitivity symptoms
When people who are sensitive to caffeine drink a few sips of coffee, they experience the situation that those who are not sensitive can experience when they drink 5-6 cups of coffee, and their adrenaline hormone levels increase rapidly and may experience some symptoms for a few hours. These symptoms include:
- High heart rate and palpitations
- Headache
- Nervousness and tremors
- Tension and anxiety
- Unrest
- Inability to sleep
People who are allergic to caffeine may experience the following symptoms, unlike people with sensitivities:
- Itchy skin
- Hives
- Swelling of the throat and tongue
- In more severe cases, breathing difficulties and anaphylaxis
Recommended amounts of caffeine
People with normal sensitivity to caffeine can drink between 2 and 4 cups of coffee a day. When you drink this amount of coffee, 200-400 milligrams of caffeine is taken. Caffeine intake of more than 600 milligrams per day is not recommended. These recommendations are for adults, and recommended amounts for children or teenagers have not been established.
People with a high sensitivity to caffeine should limit their intake as much as possible. In fact, for some, it’s best to not consume caffeine at all. People in this group can tolerate up to 30-50 milligrams of caffeine per day.
For example, these people reach the upper limit of caffeine by drinking a maximum of 1-2 cups of black or green tea. Because 1 cup of tea contains 30 milligrams of caffeine. A cup of decaffeinated coffee contains 2 milligrams of caffeine.
Causes
Many factors can cause caffeine sensitivity, including gender, age, and weight. Also, the following can cause caffeine sensitivity:
Medicines
Some medications and supplements can increase the effects of caffeine. Medicines containing theophylline and herbal supplements containing ephedrine and echinacea are some substances that increase the effect of caffeine.
Genetic
Adenosine sends a message to the brain that it is time to sleep. Caffeine binds to adenosine receptors and blocks them, maintaining alertness. In this case, although the body and brain are tired, they cannot sleep.
In a 2012 study, it was determined that people with caffeine sensitivity were affected by the process of adenosine sending signals to the brain due to a change in the ADORA2A genes. People with this gene variation are highly sensitive to caffeine.
Liver
Caffeine sensitivity is largely determined by the activity of the CYP1A2 enzyme in the liver. The more active CYP1A2 is, the less sensitive we are to caffeine. There are several factors that affect CYP1A2 activity:
- Age: CYP1A2 activity tends to decrease with age, so older people may be more sensitive to caffeine.
- Gender: Women tend to have lower CYP1A2 activity than men.
- Oral contraceptive use and pregnancy: Estrogens inhibit CYP1A2 activity, thereby increasing caffeine sensitivity.
Conclusion
Caffeine sensitivity and caffeine allergy are two different conditions. Whether you have a sensitivity or an allergy, limiting your caffeine consumption will prevent you from experiencing possible symptoms and protect your general health.