This test detects a common genetic variant that reduces the rate of caffeine metabolism in the body. Affected individuals are known as slow caffeine metabolizers. They take longer to clear caffeine from their body, and the longer caffeine stays in circulation, the higher the risk of health complications.

What are the effects of caffeine?
Caffeine binds to cellular receptors to increase nerve cell activity and stimulates the pituitary gland to release hormones and the adrenal glands to produce adrenaline. This adrenaline increases alertness, heart rate and blood pressure, and the liver releases more sugar into the bloodstream for extra energy.

The consumption of caffeine also increases dopamine levels. Dopamine is the “feel good” neurotransmitter that activates pleasure centres in certain parts of the brain. This increased dopamine is likely to contribute to caffeine addiction, in a similar way to the addictive effects of other drugs such as cocaine.

How is caffeine metabolized?
The CYP1A2 enzyme is responsible for the breakdown of 95% of the caffeine in the body. There are two common genetic variants of this enzyme – a “fast” metabolizer genetic variant and a “slow” metabolizer genetic variant. The “slow” genetic variant is associated with lower levels of the CYP1A2 enzyme and a slower rate of caffeine metabolism.

Individuals who have the “slow” genetic variant are at risk
Individuals who have inherited the “slow” genetic variant take longer to clear caffeine from their body. The longer that caffeine stays in circulation, the higher the risk of heart problems and hypertension. If an individual with slow caffeine metabolism consumes more than three cups of coffee per day, they have 2X to 4X increased risk of a heart attack and a 3X increased risk of hypertension. Reducing caffeine consumption is recommended for individuals with slow caffeine metabolism.