For the first time, researchers have a likely explanation for why even modest calorie restriction is so beneficial for overweight people. At Emory University in Atlanta, scientists found that even losing less than 10% of one's body weight can significantly reduce the activity of an enzyme that affects blood pressure.
The enzyme, called ACE for angiotensin-converting enzyme, is found in the cells lining blood vessels. The protein it helps produce causes arteries to contract, raising blood pressure. Because ACE is produced by fatty tissue, the researchers reasoned that losing fat would diminish ACE and lower blood pressure in overweight people.
Sixteen healthy but overweight and sedentary people participated in the study, eating 40% fewer calories in meals prepared by the research center's kitchen for five weeks. They lost a modest 6% to 7% of their body weight on average. But their blood pressure dropped significantly, falling about 10 millimeters of mercury on average. All but three participants had a 15% decrease in ACE.
Obesity Research, October 2002
-- Dianne Partie Lange