If you need proof that exercise helps to keep you young, look at the exciting study from King’s College in London, England reported in the Archives of Internal Medicine (January 28, 2008). The researchers showed that people who exercise regularly have telomeres in the DNA of their white blood cells that are longer than those of couch potatoes. White blood cell telomeres shorten over time and serve as a marker of a person’s biological age.

The active ends of genetic material in cells are covered with a layer of proteins called telomeres. If they weren’t, the exposed ends of the genetic material would stick to anything nearby and the cells would die. However, each time a cell divides to make two cells, a little bit of the telomere is removed. Eventually the telomere is gone, the ends of genetic material stick together and the cell can no longer divide so it dies without replacing itself. Obviously, the longer the telomeres, the longer it will take for the telomeres to be used up so the cells are viable longer.

The study compared physical activity, smoking and socioeconomic status in 2,401 sets of twins. Those who were more active had longer leukocyte telomeres than those who were less active. The researchers concluded that “The mean difference in leukocyte telomere length between the most active (who performed an average of 199 minutes of physical activity per week) and the least active (16 minutes of physical activity per week) subjects was 200 nucleotides, which means that the most active subjects had telomeres the same length as sedentary individuals 10 years younger, on average.”


Reports from drmirkin.com

Splitting fingernails
Deformed toenails
Dry skin


Dear Dr. Mirkin: Can cold air freeze your lungs?

It’s almost impossible to damage your lungs by breathing cold air when you exercise. More than 70 percent of the energy produced by your muscles during exercise is lost as heat. This extra heat can be used in your nose and bronchial tubes to warm the air as it travels to your lungs. Air inhaled at 40 degrees below zero Fahrenheit will be warmed to more than 100 degrees by the time it reaches your lungs, so your lungs will not suffer from frostbite. However, air that cold will burn your nasal membranes and cause pain in your nose that is so severe that you will lose interest in exercising very quickly and look for shelter. To protect your nose in very cold weather, you can cover it with a scarf, balaclava or face mask placed over your nose and mouth.


Dear Dr. Mirkin: Is it better to rest completely or exercise gently while recovering from an injury?

According to a study from the University of Wisconsin in Madison, it is better to exercise at low intensity while recovering from an injury or surgery (The American Journal of Sports Medicine, February 2008). The researchers found that motion during recovery limits muscle atrophy, accelerates tendon healing, and prevents joint stiffness. This explains why most doctors refer their injured or post-surgical patients for physical therapy and rehabilitation exercises.

If you are in reasonable shape and stop exercising for any reason, your muscles become smaller and weaker and are at increased risk for injury when you return to exercising. Gentle stress on a muscle or tendon can help to prevent this loss of strength. Mild exercise is a stimulus for cell growth. However, if you pull too hard on a weakened muscle or tendon, you can tear it and delay recovery.


Three New Seafood Recipes

Seafood Spanish Rice
Hot and Sour Seafood Soup
Mexican Shrimp Salad

You’ll find lots of recipes and helpful tips in The Good Food Book – it’s FREE