healthy adults, almost all caffeine goes directly into the
bloodstream, and reaches peak concentrations 15 to 45 minutes
after drinking a cup of coffee.
Caffeine travels to all parts of the body, including the fetus
in pregnant women and breast milk in nursing mothers. Because
of this pregnant and nursing women should consume as little
caffeine as possible.
Caffeine has been linked with an increased risk of osteoporosis.
New research is showing that this isn't a concern if caffeine
intakes are not excessive and calcium intakes are adequate.
To help protect bone health, women should drink one cup of
milk for every cup of regular coffee.
People are affected by caffeine in different ways. It can
help produce alertness during periods of fatigue, but too
much can cause irritability, anxiety, headaches, a racing
heartbeat and sleep problems.
As little as 200 mg of caffeine - the amount found in 1 1/2
cups of non-gourmet coffee - can make some people feel jittery
or anxious. It may take even less for children who consume
cola soft drinks.
Cutting back on caffeine often causes withdrawal symptoms
such as headaches, nausea, drowsiness, muscle tension, and
irritability in regular users. These feelings tend to be short
lived, and can be lessened by a gradual reduction in caffeine
Concern about caffeine and health exists because, over the
years, caffeine has been linked with ulcers, heartburn, heart
disease, cancer, breast lumps and birth defects. However,
regular moderate consumption of caffeine has not been proven
to cause any of these health problems.
According to Health Canada's nutrition recommendations, intakes
of 400 to 450 mg of caffeine a day (three to four cups of
coffee or tea) are okay.
But regular drinkers of unfiltered coffee beware! Dr. Terry
Graham, who has studied caffeine extensively at the University
of Guelph says "there's evidence that unfiltered coffee may
increase blood cholesterol levels".
Substances found in the oils of ground coffee, such as cafestol
and kahweol, can cause cholesterol levels to rise, but filtering
will remove them. Coffees to watch out for include those that
are made by direct boiling of ground coffee (camper coffee),
coffee made in plunger-style coffee makers and percolators
of the 1950's and 60"s, and unfiltered brews such as Turkish
coffee and espresso. You may want to drink these less often
or switch to filtered brews.