Caffeine is a brain stimulant, found in coffee, green tea and chocolate, for example and has many benefits to the body, such as increased attention, improved physical performance and stimulated weight loss.
However, caffeine should be consumed in moderation, and your maximum daily dose should not exceed 400mg per day, or 6mg per kilogram of weight, which is equivalent to about 4 cups of 200 ml coffee or 8 cups of coffee, because its excess causes harm, such as insomnia, anxiety, tremors and stomach pain.
See, in the table below, the list of foods with caffeine and the amount in each:
| Food | Amount | Average Caffeine Content |
| Traditional coffee | 200 ml | 80 - 100 mg |
| Instant coffee | 1 teaspoon | 57 mg |
| Espresso | 30 ml | 40 - 75 mg |
| Decaf coffee | 150 ml | 2 - 4 mg |
| Ice Tea Drink | 1 can | 30 - 60 mg |
| Black tea | 200 ml | 30 - 60 mg |
| Green tea | 200 ml | 30 - 60 mg |
| Mate tea | 200 ml | 20 - 30 mg |
| Energetic drinks | 250 ml | 80 mg |
| Cola soft drinks | 1 can | 35 mg |
| Guarana soft drinks | 1 can | 2 - 4 mg |
| Milk chocolate | 40 g | 10 mg |
| Semisweet chocolate | 40 g | 8 - 20 mg |
| Chocolate | 250 ml |
4 - 8 mg |
Another practical way of taking or controlling the amount of caffeine daily, can be in the form of supplements, such as capsules, or in caffeine powder in its purified form, known as anhydrous caffeine or methylxanthine. Learn more about using caffeine capsules to lose weight and have energy.
Positive effects of caffeine on the body
Caffeine works as a nervous system stimulant, blocking substances that cause tiredness and increasing the release of neurotransmitters, such as adrenaline, noradrenaline, dopamine and serotonin, which activates the body and increases energy, strength and physical performance, being widely used by practitioners of physical activities. Its use also prevents tiredness, improves concentration, memory and mood.
Caffeine is also a great antioxidant, which fights cell aging and prevents the formation of heart disease and, in addition, has a thermogenic effect, as it stimulates metabolism and speeds up heartbeat, being a great ally for weight loss. Learn more about the benefits of coffee.
Negative effects of caffeine on the body
Caffeine should be consumed in small amounts or in a moderate way, as its continuous or exaggerated use can cause side effects, such as decreased calcium absorption by the body, stomach pain, reflux and diarrhea, due to the increase in gastric and intestinal secretions, besides irritability, anxiety, insomnia, tremors and frequent urge to urinate, especially in more sensitive people.
In addition, caffeine causes physical dependence and is therefore addictive, and its interruption can cause withdrawal symptoms, such as headache, migraine, irritability, tiredness and constipation. Caffeine consumption should also be avoided by children, pregnant women, breastfeeding women and people who have very high blood pressure or heart problems.
