Fact is, caffeine is a powerful stimulant and it effects our body, mood and energy in very profound ways (whether we are a lover of its awakening effects or find that it doesn't agree with us). Whether we're looking for a jolt or making sure we're not going to be awake all night, I think we can all agree that there is power in knowing what it is we're putting into our body.
The Center for Science in the Public Interest released this listing in 2007 of the Caffeine Content of Food and Drugs.* Take a look... some of the numbers are surprising, some beverages (tea and coffee notably) have quite a range, based on production and preparation methods.
Caffeine has both its perks and its quirks - get in tune with both how it serves you and how it doesn't.
- Improves alertness, focus, and concentration
- Performance endurance: one study has shown that 3-9 mg of caffeine per kg of body weight consumed 1 hour prior to exercise increases endurance
- Constricts blood vessels and helps the body absorb some medications more quickly (which is why it is added to some pain medications)
- Mood-booster: at 200 mg, people report an overall increased sense of well-being, happiness, alertness and sociability
- Cardiovascular problems: increases heart rate and elevates blood pressure; both decaf and regular coffee
- Stress and emotional disturbances: caffeine stimulates the excretion of stress hormones, producing increased levels of of anxiety, irritability, muscular tension, indigestion, insomnia and decreased immunity; depression may occur as part of the letdown as effects wear off
- Memory: decreases blood flow to the brain by as much as 30%, negatively effecting memory and mental performance
- Weight gain and blood sugar swings: stimulates a temporary surge in blood sugar, followed by an overproduction of insulin, causing a blood sugar crash within hours - this roller coaster is a leading cause of weight gain since insulin's message to the body is to store sugar as fat
- GI problems: increases risk for ulcers and creates a highly acidic environment in the stomach, which can lead to heartburn and acid reflux disease
- Nutritional deficiencies: inhibits the absorption of some nutrients and causes the urinary excretion of calcium, magnesium, potassium, iron and trace minerals
Dehydration myth: Contrary to popular myth, nothing I have read convinces me that caffeine or coffee itself is dramatically dehydrating. That being said, coffee is slightly diuretic (meaning it causes you to urinate more, excreting some vital nutrients with it) and does often trigger bowel movements - both of which take water away from the body. It does also have many dramatic effects on the body's metabolism, hormones and chemistry (it is very acidic). Water is one of the most powerful tools for helping our body to process and cleanse out what we put into it. Please do consume adequate fresh clean water. Adding lemon to your water can help to balance some of the acidic effects of coffee (as lemon has alkalizing effects in the stomach and body).
If you feel like the amount you consume in a day may be excessive, think about why you feel the need or desire for so much of it (it is a drug substance - and addictive - after all) and what might be missing (sleep, energy, nutrition).
*Note that: "Most information was obtained from company web sites or direct inquiries. Serving sizes are based on commonly eaten portions, pharmaceutical instructions, or the amount of the leading-selling container size. For example, beverages sold in 16-ounce or 20-ounce bottles were counted as one serving."