April 5 , 2002

In this study, 15 young men (average age was 29) without any evidence of heart disease were alternately fed high-fat and low-fat meals. Using a special ultrasound machine that measures the coronary arteries' ability to dilate in order to increase blood flow, the researchers evaluated coronary artery reserve before and after the meals. They also measured blood levels of triglycerides (a fat) before and after each meal.

Within 5 hours of the fatty meal, the average triglyceride level in the blood almost tripled, while coronary artery flow reserve decreased by almost 20%.

Following a low-fat meal, no significant changes were noted in blood triglyceride levels or coronary artery flow reserve.

Although the study only evaluated a very small number of volunteers, it provides intriguing insight into the possible adverse effects on coronary artery function following even a single high-fat meal. While such rapid changes in coronary artery flow reserve may not be significant in young people without heart disease, such changes might be important in older patients with compromised heart function due to coronary artery disease. At a minimum, it is something to consider the next time you are tucking into a double cheeseburger and french fries....

EXERCISE & BLOOD PRESSURE
With recent research showing that the majority of us will eventually develop high blood pressure severe enough to require treatment, strategies that reduce the risk of developing this condition are more important than ever. Maintaining your body at a healthy weight, eating a healthy diet, and remaining physically fit are all crucial to such a strategy.

A study in the Annals of Internal Medicine retrospectively analyzed 54 different research trials that measured the effects of exercise on the risk of developing high blood pressure. Using a technique called meta-analysis, the authors evaluated the previous studies to find statistically significant factors that were confirmed in most or all of these studies.

This meta-analysis study found that regular and habitual aerobic exercise was associated with a significant reduction in blood pressure among people with normal blood pressure and in those with high blood pressure. This beneficial effect was also seen in people who were of normal weight and in those who were obese.

This study adds to the growing scientific evidence that 30 minutes or more of moderate exercise, when performed 4 to 5 times per week, can substantially reduce your risk of dying from the two most common causes of death in the developed world: heart attack and stroke.

Of course, please remember to first consult your physician if you are planning to begin a new exercise program.

CAN COFFEE REDUCE YOUR RISK OF TOOTH DECAY?
The Journal of Agricultural and Food Chemistry features an interesting study looking at the effects of coffee on Streptoccocus mutans, the bacteria thought to be primarily responsible for tooth decay.

The researchers found that coffee inhibited the decay-causing bacteria from sticking to artificially created tooth surfaces in the laboratory.

Of course, this experiment in a test tube cannot perfectly simulate the conditions on the surfaces of our teeth. Additional research will therefore be needed to see if this finding holds up under the more complex conditions present within our mouths.

Dr. Robert A. Wascher