Monday, April 13, 2009

Why Meat from Mammals is Risky

A study of more than 500,000 Americans over 40 shows that those who consume the equivalent of at least a hamburger a day have a 30 percent increased chance of dying during the next 10 years, mostly from heart disease and cancer. Cold cuts, sausage and other processed meats also increased the risk (Archives of Internal Medicine, March 2009). This agrees with many other studies showing that eating meat from mammals is associated with increased risk for heart attacks, arthritis, and several types of cancer. The study found that eating fish, chicken, turkey and other poultry decreased the risk of premature death.

Most authorities still attribute the high mortality in meat eaters to the saturated fats and cholesterol in meat. This makes little sense since 1) poultry is also a rich source of saturated fats and does not increase premature death, cancer or heart attacks; 2) people who eat a diet rich is saturated fats from palm, palm kernel and coconut oils are not at increased risk for premature death; and 3) eggs and shell fish are extremely rich sources of cholesterol and they are not associated with premature death. I believe that the most likely explanation for the increased risk for heart attacks and premature death in meat eaters is inflammation from the glycoprotein Neu5Gc; see my reports from November 9 and November 16, 2008

Wednesday, April 08, 2009

High Insulin = High Breast Cancer Risk

Women who have high levels of insulin are at high risk for developing breast cancer (Journal of the National Cancer Institute, January 2009). Insulin stimulates breast cells to grow. Women who are most likely to have high levels of insulin are those who are obese, store fat primarily in their bellies, do not exercise, eat lots of refined carbohydrates (sugar and flour), and lack vitamin D. Furthermore, people with diabetes who get cancer are 40 percent more likely to die earlier than cancer patients who are not diabetic (Journal of the American Medical Association, February 2007). Dr. Frederick Brancati of Johns Hopkins University in Baltimore combined the results of 23 studies involving about 125,000 people in 10 countries including the United States, Australia and the Netherlands. People with high blood sugar levels are at increased risk for cancers of the uterus, breast, colon, pancreas, endometrium, liver and bladder. Those with diabetes have a 76 percent higher risk of death from cancer of the uterus, a 61 percent higher risk for breast cancer, and a 40 percent increase for colon cancer. Furthermore, diabetics are at higher risk for heart disease, stroke, kidney damage and blindness.

Sunday, April 05, 2009

Hard exercise should not reduce libido

If hard exercise or training causes you to lose interest in making love, get a medical check-up. If your doctor finds nothing wrong with you, you may be training too much. Most endurance athletes have normal blood levels of the male hormones, testosterone and dihydro-testosterone, and lose neither sexual desire nor sexual performance (Journal of Endocrinological Investigation, October 2008).

Endurance athletes who have low levels of testosterone usually have normal blood levels of LH and FSH, the brain hormones that control testicular production of testosterone. Defective testicular production of testosterone is usually associated with very high levels of brain hormones. That means that reduced sexual desire associated with endurance training is governed by the brain, not testicular damage, and is often part of an overtraining syndrome.

Training for competition is done by taking an intense workout on one day, feeling sore on the next, and going at reduced intensity for as long as it takes for the soreness to go away. Taking intense workouts when you feel soreness causes muscle injuries and fatigue that affects all your organ systems, including your sexuality. Once you develop an overtraining syndrome, it can take a very long time to recover. If this has happened to you, I recommend jogging slowly each day and stopping each workout immediately when your legs feel heavy or sore. When you feel better, you can start to train intensely again, but be sure to include slow recovery days in your training program.

Thursday, April 02, 2009

Who should restrict salt? (and who should not?)

Most doctors recommend salt restriction for all their patients, even though many will not develop high blood pressure from high-salt intake and some may even be harmed if they restrict salt. Heavy exercisers lose so much salt that they have to take in lots of salt just to replace what they lose through sweat.

A study from China shows that people with metabolic syndrome are the ones who are most likely to develop high blood pressure from a high-salt diet and that high levels of insulin may cause the rise of blood pressure that is associated with increased salt intake (Lancet, published online March 2, 2009). Metabolic syndrome occurs when a person's cells lose their ability to respond adequately to insulin and blood levels of sugar rise too high. It is caused by eating too much refined carbohydrates, being overweight, not exercising, and lacking vitamin D and is characterized by storing fat primarily in the belly, having a thick neck, high blood triglycerides, low blood good HDL cholesterol, high blood sugar, and eventually liver damage and all the side effects of diabetes. People with metabolic syndrome had a greater rise in blood pressure with increased salt intake and drop in blood pressure with salt restriction. The more risk factors for metabolic syndrome a person had, the greater the rise and fall of blood pressure with changes in salt intake.

If you are concerned about your blood pressure, you can buy an inexpensive wrist cuff and check your blood pressure at bedtime. If it is below 120, you do not need to restrict salt. If you store fat primarily in your belly rather than your hips, your HDL is below 40, your triglycerides are above 175, or you have a blood sugar above 100 two hours after a meal or an HBA1C above 5.9, you probably should restrict salt and definitely should work to correct the causes of metabolic syndrome (described above).