Thursday, 31 January 2008

Caffeine recommendations

I just rechecked and although the recommendations are 400mg caffeine for the average person,
for women of childbearing age, the new recommendation is a maximum daily caffeine intake of no more than 300 mg. That's the equivalent of only one grande Starbucks brewed coffee.

For children age 12 and under, Health Canada recommends a maximum daily caffeine intake of no more than 2.5 milligrams per kilogram of body weight. Based on average body weights of children, this means a daily caffeine intake of no more than:

45 mg for children aged 4 - 6;
62.5 mg for children aged 7 - 9; and
85 mg for children aged 10 - 12.

Those recommended maximums are equivalent to about one to two 12-oz (355 ml) cans of cola a day.


Vany said...

Interesting. What are the (long term) health risks associated with excessive caffeine intakes (i.e. over 300mg)?

Sybil Hebert, RD said...

Hey Vany,

I just wrote a great post and lost it!! Here goes again!

From what I've read, it's difficult to link precise intake levels of caffeine to specific health effects because tolerance to caffeine differs widely from person to person. Some people that are more sensitive to caffeine can suffer from insomnia, headaches, irritability and nervousness if they exceed the recommended intake of caffeine (or even if they consume less than that!).

A 1994 study showed that there was an association between excess caffeine intake and a lower bone density, independent of age, obesity, years since menopause, the use of tobacco, estrogen, alcohol, thiazides, and calcium
supplements IF dietary calcium intake was low.

Children that consumed too much caffeine were found to have sleeping problems.

A recent study of 1063 pregnant women showed that those that consumed 200mg caffeine or more (especially earlier in their pregnancies) had twice the number of miscarriages as those that didn't consume any caffeine. That's why the recommendations have changed fr pregnant women, women that are trying to become pregnant and women that can become pregnent, to <300mg a day. Actually, the researchers suggest that women in their first trimester avoid caffeine altogether. (I may post this study on the blog since it's getting lots of buzz!).

As for long term health risks, I didn't find anything documented. Those types of studies are hard to conduct because there are so many interfering factors. For example, people that have a high caffeine intake may eat less fruits and vegetables or may be less physically active or may smoke. It's hard to control for all those factors!