Health
Muscle mass, strength and muscle cell function decline with increasing age. Ageing causes a loss of functional motor units (nerves and muscle cells), abnormal mitochondria (energy centers of the cells), death of nerve cells and destruction of DNA. Gradually, muscle cells lose the ability to repair damage, resulting in a further decline in muscle function. Training with weights can restore some of the lost muscle function in older people. Mark Tarnopolsky and Adeel Safdar of McMaster University in Canada concluded from a literature review that the combination of training with weights and creatine monohydrate generates satellite cells that have the characteristics of young muscles. These satellite cells are integrated into the old muscles, which can reverse many of the effects of ageing. The additional intake of conjugated linoleic acid (CLA) helps to reduce body fat and build lean body mass. Creatine supplements in combination with training with weights increase the number of muscle cell nuclei (the genetic centers of the cells), making the muscles "younger".
The scientists concluded from these findings that the combination of training with weights, creatine monohydrate and CLA has important anti-ageing effects. However, it is not known how long these changes can be maintained.
(Applied Physiology Nutrition Metabolism, 33: 213-227, 2008)
A reduction in low density lipoprotein cholesterol (LDL) by just a few points reduces the risk of heart disease and stroke. Some studies showed that replacing animal protein in the diet with soy protein lowered total cholesterol and LDL cholesterol levels. Soy increases the activity of liver enzymes that break down cholesterol. In 1999, the U.S. Food and Drug Administration recognized the claim by soy manufacturers that a diet containing 25 grams of soy protein per day is good for the heart and lowers cholesterol. A year later, the American Heart Association recommended that people with an increased risk of heart attack should include soy products in their diet.
Unfortunately, there was little conclusive evidence that soy is good for the heart or that it lowers blood cholesterol levels. Most of the studies that did show positive effects used very few subjects and often had statistical and study design problems.
The American Heart Association changed its position in 2006 and concluded that soy protein or isoflavones (estrogen-like chemicals in soy products) do not lower LDL cholesterol, triglyceride levels or blood pressure, nor do they raise HDL cholesterol (the "good" cholesterol).
Australian scientists confirmed this when they found that high soy protein consumption had no effect on total cholesterol or LDL cholesterol levels.
However, eating soy hamburgers and soy hotdogs instead of their animal counterparts, which are rich in saturated fat, could reduce saturated fat intake and thus improve cardiovascular health. Although soy products do not have a direct effect on cholesterol metabolism, they may improve the overall quality of the diet.
(WebMD Health News, August 8, 2008; American Journal Clinical Nutrition, 88: 298-304, 2008)
