How much caffeine is in...?

Caffeine is one of such substances, to which there's no doubt that may influence positively the sports shape. However, the issue of the optimal dose of caffeine causes a lot of controversies, as well as the matter of the choice of its source. Of course, the easiest option is to aply this compound in a form of a supplement, but if it also occurs in many natural food products, you can get use of them.

You should definitely read:

Caffeine and the matter of magnesium

Why is it worth to know the amount of caffeine in food and beverages?

Caffeine may be used in different ways. In sports it is usually used because of its ergogenic properties (positive influence on the effort abilities), as well as because of the influence on the metabolic processes (increased energy expenditure connected with higher thermogenesis and spontanuous physical effort). However, it's good to know that, in order to cause the results mentioned above, some level of caffeine intake has to be obtained, and it equals at least 3mg per 1kg of body mass (this amount is pointed by sparce data, majority of studies suggest the need of 5-6mg per 1kg of body mass, which is a lot). This is the first reason why it would be good to know the content of caffeine in particular foodstuffs.

Another thing is the fact, that caffeine also has some flaws – it may increase the excretion of magnesium and calcium form te body. But again, it's the dose that matters. In most cases you need about 500mg of this substance to be able to notice this effect with such intensity, that it disturbed the daily balance of calcium and magnesium.

Additionally, there's a lot of information that caffeine may be harmful for the developing fetus. During pregnancy, it is advised to limit the intake of this substance to 200mg per day (from all sources), and some authors suggest the limit of 100mg...

The content of caffeine in beverages and foodstuffs

Unfortunately, it's impossible to give detailed information on the particular amount of caffeine in foodstuffs and beverages. It results from large fluctuation in its concentration in food products. That's why the average numbers, taken on the basis of the analysis of various studies, are assumed as right. The estimate content of caffeine in beverages and foodstuffs is following:

  • roasted coffe beans – 2 teaspoons (about 5g of dry product): 57mg

  • ground roasted coffe beans – 2 teaspoons (about 5g of dry product): 86mg

  • instant coffee made of 2 teaspoons (about 4g of dry product): 117mg

  • green tea in bags – 1 bag (2g of dry product): 30mg

  • green tea leaves – 1 teaspoon (2g of dry product): 33mg

  • black tea in bags – 1 bag (2g of dry product): 38mg

  • black tea leaves – 1 teaspoon (2g of dry product): 33mg

  • natural cocoa – 2 teaspoons (5g of dry product): 7mg

  • bitter chocolate – 1 bar of chocolate (100g): 60-80mg (depending on the content of cocoa)

  • milk chocolate – 1 bar of chocolate (100g): 21mg

  • coca-cola – 1 glass (250ml): 23mg

  • pepsi – 1 glass (250ml): 25mg

This list was prepared on the basis of data from the publications found below:

http://www.ptfarm.pl/pub/File/bromatologia_2009/bromatologia_3_2009/BR3%20s.%200776-0781.pdf

http://www.ptfarm.pl/pub/File/Bromatologia/2013/4/BR%204-2013%20s.%20449-454.pdf

Summary

As you can notice, foodstuffs, sometimes even inconspicuous (cocoa, chocolate, cola, tea) may be the sources of caffeine in the amount which significantly influences the daily intake of this compound. This fact may be used in referrence to planning daily ergogenic and metabolic doses, as well as in setting the daily safe intake limits.