Muscle Metabolism - Muscle Loss

"We tend to think of muscle loss as a problem of old age," says researcher Chhanda Dutta. "But it’s something that starts much earlier in our lives."
Men and women begin to lose significant muscle mass in their 40s and 50s. Some of that is due to age and some is due to a sedentary lifestyle. The chief of the Clinical Gerontology Branch at the National Institute on Aging (NIA) in Bethesda, Maryland also attributes too little protein in the diet can accelerate the loss.
Unfortunately, most people think they’re fine because the early muscle loss doesn’t hold them back. That’s until they reach a point where they can no longer go grocery shopping or live independently. At that point you are in trouble.
"There are probably several dozen ways sarcopenia (pronounced SAR-co-PEEN-yuh) develops, and that’s part of the problem of trying to treat it,"says John Morley, professor of geriatric medicine at St. Louis University in Missouri.
Among the causes:
* Slowdown in muscle metabolism. As we get older, our ability to synthesize muscle protein decreases. You can increase the size of the muscle fibers you have, but you’re not really making new muscle tissue.
* Too little muscle-stimulating physical activity. For 80 to 90 percent of adults, if they don’t do the right kind of physical activity regularly, they’re going to end up with sarcopenia, Research shows that seniors benefit from a regular regimen of tennis and my Senior Tennis League shows it. Without the activity on a regular basis, they’re going to end up with sarcopenia by the time they’re in their 60s and 70s. Even people who walk or run regularly may be on the road to later problems. That’s because aerobic exercises like walking, running or cycling don’t challenge some of your major muscle groups.
* Genetic differences. We all know middle-aged people who look like they have as much muscle as the average 25-year-old. That’s probably because they’ve inherited good genes. They’ve probably also stayed reasonably active throughout their life. But those people are the exceptions.
* Gender differences. While both men and women lose muscle as they age, the functional consequence for women is huge. That’s because women start out with less muscle and wind up much weaker. Since women live longer and are more likely to live alone, they’ll be dealing with the effect of sarcopenia much more than men.
* Hormonal deficiencies. Testosterone (in men) and estrogen (in women) stimulate the growth of muscle tissue, but both decline with age. Also critical for muscles is insulin-like growth factor (IGF), which drops dramatically as we grow older. But don’t assume that taking hormones will reverse the effects of muscle loss.
* Changes in diet. We eat less as we get older. In particular, we eat less protein, the nutrient that builds muscle tissue.
* Loss of nerve cells. As we age, we lose not just brain cells, but also motor nerve cells in our spinal cord that send information out to the muscles. By the time we’re into our 60s and 70s, we’ve lost up to half our motor nerve cells.
Without nerve cells to stimulate them, muscles wither away. The remaining healthy motor nerve cells can compensate by adopting the "orphaned" muscle fibers.
How can you avoid the damage done by muscle loss (sarcopenia)?
* "Resistance exercise is what people should be doing before they think of anything else," says st. Louis University’s John Morley. The results can be dramatic.
"Women in their 40s and men in their 60s lose muscle strength at a rate of 12 percent per decade," says Ben Hurley. A professor of exercise physiology at the University of Maryland in College Park. (Hurley is married to Nutrition Action senior nutritionist Jayne Hurley.)
But with two months of resistance training, they can increase their strength by 40 percent. "In other words, they can reverse two decades of typical muscle strength deterioration in 50 days," says Hurley.
Strength building has other benefits. "Women who do strength training gain more self-confidence and self-esteem, they sleep better, and they’re less likely to be depressed." says Tuft’s Miriam Nelson.
Strength training also makes aerobic exercise more enjoyable because you’re more fit and less prone to injuries. The key to stemming muscle loss with exercise is to strengthen the big muscles around the thighs, arms, shoulders, and back.
To gain muscle you need to consume 50 percent more protein than the RDA level. To reach that much, your daily protein target (in grams) should be about half your weight (in pounds). That’s about 65 grams of protein a day for someone who weights 125 pounds. I’ve found that to be effective in my own case.
The good news is that you can get enough protein without cooking elaborate meals every night. Who knew that half a cup of cottage cheese or a chicken breast could help keep you looking and feeling younger? Be sure to choose low fat or fat free cottage cheese for an even better benefit!

Trans Fat's Departure From Food Supply

Trans Fat has been causing 50,000 deaths a year in the United States according to an epidemiological study led by Walter Willett, the chairman of the nutrition department at the Harvard School of Public Health. Those studies suggested that trans fat does more harm than raise "bad" and lower "good" cholesterol. Unlike other academics, Willett used the news media to campaign against trans fat.
In 2003, the F"D"A took a crucial step by requiring Nutrition Facts labels to list trans fat. That told the food industry in no uncertain terms that trans fat was a real problem. The next year an FDA advisory committee informed the agency that, gram for gram, trans fat is even more harmful that saturated fat that’s in meat and dairy foods.
Back in the 1980s it was unclear if trans fat, which is found in partially hydrogenated oil, was harmful. That changed when two Dutch researchers discovered that trans fat raises levels of LDL (bad) cholesterol in our blood and lowers levels of HDL (good) cholesterol.
Labeling has led many prominent companies to get rid of most or all of the trans fat from their foods. They don’t want their products criticized for being high in trans fat.
Frito-Lay, Kraft, Con Agra and other are dumping trans and generally using much healthier oils, especially in their fried foods. Unfortunately Pillsbury, General Mills, Marie Callender’s and others haven’t done much to break their trans habit.
Chili’s, Ruby Tuesday, Wendy’s, KFC, Taco Bell, Arby’s, and many others have largely eliminate—or plan to do so in the near future, at least from their fryers. It’s trickier to fix the problem in baked goods. Most breads have hydrogenated fats and high fructose corn syrup listed in fine print under ingredients. McDonald’s by far the biggest chain, has switched to healthier oils in over 1,000 restaurants so far. It has already eliminate trans from its outlets in much of Europe, Australia, and some other countries.
One barrier to switch oils is the limited supply of the alternatives. Fortunately, the sharp increase in demand for the trans-free oils has spurred farmers and processors to ramp up production of canola, high-oleic canola, sunflower, and low-linolenic soybean oil.
Although the industry is making great progress, the FDA needs to take the two critical steps that would finish the job of protecting the public:
* Require restaurants immediately to put notices on menus and menu boards if their foods contain trans fat.
* Revoke the "generally recognized as safe" status of partially hydrogenated oil. It’s ridiculous for the FDA to call that oil safe when the agency agrees that trans fat causes heart disease. The time has come to get partially hydrogenate oils—and their trans fat—out of our food supply.
Since January 2006, when the government started requiring foods to include the artery-clogging fat on their Nutrition Facts labels, many companies have ditched the partially hydrogenated oils that contain trans fat. Primary studies suggest that trans may promote diabetes which is why experts recommend less that 2 grams of trans fat per day.
Just remember that foods that boast about their "0" grams trans fat could still be high in sugar, salt, refined carbs or saturated fat. A third of a bag of Pop-Secret Homestyle Popcorn delivers 5 grams of trans fat plus 3 trams of saturated fat. The whole bag can deliver more than a day’s heart gunk by the time the credits roll.
Americans will have to step up their efforts to eat healthy and read the Nutrition Facts and especially the ingredients. If you don’t know the facts you are risking your health and heart. Diligence is the best way to change our food supply and enable us to eat healthy.