Madam Chair, Members of the House of Commons, thank you for having me.
Caffeine is an alkaloid methylxanthine, which is probably the most consumed psychostimulant in the world today. It is found everywhere: in tea leaves, in coffee beans, in yerba mate leaves and in guarana seeds. Caffeine is contained in many natural substances, but it is mainly found in consumer products, such as carbonated drinks, energy drinks, chocolate and candy. Last week, I even read that caffeinated flavoured water will be released soon. Caffeine is the main active ingredient in energy drinks. Supposedly, it is added for its stimulant properties.
The amount of caffeine found in food varies widely. People who choose to consume caffeine should not exceed the maximum daily intake recommended by Health Canada, whose main responsibility is the health of Canadians. The recommended maximum intake is 400 mg for adults and 2.5 mg per kilogram for children, that is, very small doses. For children from 1 to 5 years of age, the maximum intake is 45 mg, which is barely more than what a bottle of cola contains.
Consumption statistics show that most Canadian adults do not exceed the recommended maximum intake of 400 mg. The caffeine they consume comes from diverse sources: 60% from coffee, 30% from tea and 10% from various sources, such as cola beverages, chocolate, and so on. However, we already know that children aged 1 to 5 get 55% of their total caffeine intake from cola beverages. That is to say, cola drinks are their main source of caffeine.
The effects of caffeine consumption are numerous. Caffeine improves mental alertness, concentration, reaction time and energy levels. We also know that it raises a person's fatigue threshold and lowers their reaction time. We know that it increases catecholamine secretion, that it improves free fatty acid mobilization and that it increases triglyceride use. We also know that it has cholesterol-related effects and that it improves muscle fibre contraction.
However, we are unable to show that doses found in drinks have systematic effects, aside from that of stimulating the central nervous system. Even moderate consumption can have undesirable effects. Even the caffeine contained in beverages can cause side effects, such as sinus tachycardia, increased heart rate, palpitations, insomnia, restlessness, nervousness, shaking, headaches and abdominal pains, depending on the quantities consumed.
Caffeine is a known, albeit mild, diuretic. By consuming 250 mg of caffeine, a person can experience a significant increase in diuresis. However, caffeine is not a powerful diuretic.
As for caffeine consumption increasing the risk of coronary disease, the available data is still very contradictory. A number of studies on the subject were conducted using coffee that contained substances other than caffeine. Therefore, we cannot rule out the effects of, for instance, diterpenes or chlorogenic acids on heart rate increase.
Hypertension is a major coronary disease risk factor, as are stroke and heart failure. We know that when very high doses of caffeine are consumed, blood pressure can rise, but it then becomes stable with chronic consumption. So, no study has demonstrated a significant difference in blood pressure or an increase in blood pressure in chronic coffee consumers.
Current data shows that moderate caffeine consumption, that is less than 400 mg a day, should not adversely affect the cardiovascular health of the general population. However, we do not possess sufficient epidemiological data to come to any firm conclusions as to the risk of coronary disease or mortality associated with caffeine consumption in excess of 1,000 mg.
Clearly, we are not talking here about acute intoxication. The consumption of carbonated drinks is not expected to cause acute intoxication, since these beverages contain only 15 mg of caffeine per kilogram. Regarding chronic intoxication, we know that chronic caffeine consumption can cause, among other things, a syndrome called caffeinism, which is quite different from caffeine withdrawal syndrome. Caffeinism develops through caffeine consumption.