The dosage of caffeine can vary depending on factors such as individual sensitivity, body weight, and tolerance. However, typical recommendations suggest consuming no more than 400 milligrams of caffeine per day for most healthy adults, which is roughly equivalent to:

- About four 8-ounce cups of brewed coffee
- About 10 cans of cola (12 ounces each)
- About two "energy shot" drinks
- About two 16-ounce servings of energy drink

It's important to note that caffeine content can vary widely between different beverages and products, so it's essential to check labels or research the specific caffeine content of what you're consuming. Additionally, some people may be more sensitive to caffeine and may need to consume less to avoid negative effects such as insomnia, jitteriness, or increased heart rate. Pregnant women, individuals with certain medical conditions, and those taking certain medications may need to limit their caffeine intake further. Consulting with a healthcare professional can provide personalized recommendations based on individual circumstances.

Here's a breakdown of typical caffeine content in some common beverages and products, measured in milligrams (mg):

- Brewed Coffee (8 oz): 95 mg
- Espresso (1 oz): 63 mg
- Black Tea (8 oz): 47 mg
- Green Tea (8 oz): 29 mg
- Cola (12 oz): 35-50 mg
- Energy Drink (16 oz): 160 mg
- Energy Shot (2 oz): 200 mg

Remember, these are approximate values, and caffeine content can vary depending on factors like brewing method, brand, and serving size.