Caffeine is Healthy and May Help Weight Loss
By Richard Lipman M.D.
Caffeine is America's drug. Almost 90% of Americans ingest caffeine in one way or another. There is no doubt of its effects on mental alertness and well being, but what about the long term. Is there a sustained, lifetime, benefit or harm from drinking coffee regularly? Does drinking caffeine loaded beverages have heart or blood pressure problems. Does caffeine help or hinder weight loss?
Caffeine is a natural component of chocolate, coffee and tea, and is used as an added energy boost in most colas and energy drinks. Fifty six percent of Americans drink coffee everyday- three cups each, more than 336 million cups a day. This data from the National Coffee Association reveals that more than 112 million Americans drink coffee everyday. Caffeine is the drug and coffee is the delivery vehicle.
Bennet Weinberg has written two books on coffee the most recent "The Caffeine Advantage." Weinberg says caffeine is the world's most popular drug. Caffeine works by stimulating adrenaline levels all over the body. Two cups of coffee contain 250 mg. of caffeine enough to triple adrenaline in the blood. A single eight-ounce cup of regular brewed coffee has about 150 mg of caffeine. Espresso has about double the caffeine of regular coffee.
Our brain thinks caffeine looks like adenosine. Caffeine, therefore, binds to the adenosine receptors which has the effect of blocking the slow down effects of adenosine. That's why a shot of coffee late in the afternoon gives us energy, the normal rise in adenosine as the result of working all day is blocked at the cellular level. Nerve cells begin to fire when adenosine is blocked. Thinking there must be an emergency somewhere, the adrenal gland makes adrenaline and all of the side effects of caffeine occur.
Here are some of the side effects of caffeine:
- Eyes: blurred vision
- Brain: Alertness, thirst, anxiety, irritability, insomnia,
- Sense of balance: dizzy
- Mouth: dry
- Skin: pallor, cold sweats, flushing
- Heart: rapid heart beat, slight blood pressure rise
- System: low blood sugar
- Stomach: nausea, ache
- Muscle: slight tremor
- Respiratory: fruit-like breath odor
- Urinary: increased urination, mild diuretic effect
- Bowels: loose bowels
Since coffee is the main source of caffeine worldwide, the safety of caffeine has been obtained from numerous coffee studies:
Cardiovascular Disease:
Blood pressure was found to be slightly elevated in a group of 1000 former medical students drinking large amounts of coffee. However, there was no indication of hypertension due to heavy coffee intake. A new study of coffee drinkers in Finland - one of the biggest coffee consumers - brings good news. The study found no evidence that coffee drinking is connected to heart disease. The study did find that heavy coffee drinkers have poorer health habits than those who drank no coffee. Those who drank coffee heavily were more likely to smoke and have greater amounts of body fat. More important however, deaths from heart disease were highest in those who did not drink coffee. In terms of strokes, coffee drinkers had a 23% lowered incidence compared to people who did not drink coffee. Daily coffee consumption among drinkers averaged 5.7 cups.
Diabetes:
A 2003 study by researchers at Harvard found that people Coffee contains antioxidants and can improve insulin sensitivity and reduce the risk for incident Type 2 diabetes, the study showed. Among adult males, coffee helps prevent blood clots that cause embolic strokes.
Brain impairment:
Coffee appears to provide strong protection from
Parkinson's disease. Other long term studies have found less dementia in coffee drinkers.
Caffeine and Weight Loss
Caffeine and Weight Loss studies indicate that drinking coffee or tea with caffeine may slightly boost weight loss or prevent weight gain. But there's no evidence that increased caffeine consumption results in significant or permanent weight loss... In addition, some studies found that decaffeinated coffee may contribute to modest changes in weight, suggesting that substances or factors besides caffeine may play a role in weight loss.
- Appetite suppression: Caffeine may reduce appetite for a short time. But there's not enough evidence to show that long-term consumption aids weight loss.
- Calorie burning: Caffeine may help burn fat. But this is not significant so you will not see it on a scale. You need to be careful not to confuse studies on rats in a laboratory and humans. Just because metabolism may increase in lab animals, this data cannot be transferred to humans.
- Water loss: Caffeine acts as a mild diuretic, the mild water loss may temporarily decrease your body weight
One study observed the effects of green tea (300 mg.) on metabolism and weight loss. For the group of people who used the higher levels of caffeine, weight loss numbers were also higher which suggested a connection between caffeine intake and increased metabolism. There was a suggestion of decrease in appetite as well. However, the group's ability to maintain that weight loss was less.
The answer is that caffeine is probably weight neutral. It neither helps nor hinders weight loss. The answer, so far, contains good news and bad news. The good news for coffee drinkers is that most of the long-term results are positive. No clear harm seems to occur with caffeine ingestion.