Cancer cells are different from normal cells. Every normal cell in your body has programmed into its genetic material, a process called APOPTOSIS, that lets it live and multiply only so long and then it dies. For example, skin cells live 28 days and die; cells lining your mouth live 24-48 hours and die; and red blood cells live up to 120 days. Cancer cells lose their ability to die. They try to live forever and they kill by going from one type of tissue to invade another type of tissue and destroy it. For example, breast cancer cells can eventually spread to your brain or lungs. They replace and destroy these tissues, and you die because your brain or lungs are not able to work properly.
Cancer cells grow and multiply so rapidly that they need huge amounts of the sugar, glucose, to supply them with the energy necessary for growth. Let me explain why cancer cells need so much sugar.
HOW CELLS GET ENERGY: All cells get their energy from two major processes:
• glycolysis, and
• the Krebs Cycle.
Normal cells primarily use the Krebs Cycle for energy since it is more efficient and provides more energy. However, cancer cells do not use the Krebs Cycle well, and therefore must depend on glycolysis. Because they use this inefficient pathway for energy, cancer cells that have forgotten to die have an incredible increase in need for energy from the sugar, glucose. Since insulin drives sugar into cells, insulin and ILGF-1 (insulin-like growth factor-1) feed cancer cells glucose, encouraging them to grow and multiply.
CANCER CELLS USE GLYCOLYSIS: In the early 1920s, Otto Warburg demonstrated that cancer cells can live without oxygen by getting their energy from glycolysis. Since glycolysis uses the single sugar, glucose, for energy, cancer cells use tremendous amounts of glucose to grow. Since cancer cells depend on glucose for energy, anything that interferes with the body’s normal use of glucose supplies more sugar to the growing cancer cells, which will increase growth of an existing cancer and risk for new cancers. This is one of the reasons why diabetes and excess weight increase risk for cancer (see the third report below).
MITOCHONDRIA: In every cell are from a few to hundreds of small areas called mitochondria. They provide energy for cells through the Krebs Cycle, which is far more efficient than glycolysis, the process that supplies energy inside cells but outside the mitochondria. All cells need functioning mitochondria, where the Krebs Cycle occurs, to have apoptosis. Cancer cells have defective mitochondria which forces them to use glycolysis for energy. Since cancer cells have defective mitochondria, and do not use the Krebs cycle effectively, they do not have apoptosis, so they live indefinitely and kill by invading and destroying normal cells.
A CURE FOR CANCER? Researchers today are trying to cure cancer by blocking glycolysis. This could force mitochondria to become active again and use the Krebs Cycle for energy so that the cells can stop being cancerous and regain apoptosis, their programmable cell death. The chemical dichloroacetic acid (DCA), which increases the chemical reactions of the Krebs cycle in mitochondria, has been shown to kill cancer cells in laboratory tests and in animals. Anything that activates or restores mitochondria can restart apoptosis and cause cancer cells to kill themselves. At the University of Alberta, Dr. Evangelos Michelakis is doing research on DCA. Another activator of mitochondria, 3-BrOP, is being studied at The University of Texas M. D. Anderson Cancer Center. 2-deoxyglucose (2-DG) is being used at Emory University School of Medicine, and lactate dehydrogenase A is being researched at Johns Hopkins University.
DIANA’S FATHER WORKED WITH KREBS: In the 1930′s, my wife Diana’s father, Donald Purdie, was a professor at Cambridge University in England and spent his career working with Nobel Prize winner, Hans Krebs (1900-1981) whose research group worked out most of the chemical reactions that supply energy for cells. Her father published with Hans Krebs.
In the early 1940s, the Germans bombed England daily. Donald Purdie accepted the professorship and chair of the Department of Chemistry at Raffles College in Singapore, to get away from the war in Europe. Diana was born in Singapore in January 1942. Two weeks later, the Japanese invaded Singapore and her father was taken prisoner. The Japanese killed this great academic, starving him to death while he was forced to do manual labor to build the Burma-Thai railroad.
Diana and her mother and brother escaped on a boat that arrived in Bombay six weeks later. They then came to the United States and her mother didn’t learn of Donald’s death until three years later.
A study from New Zealand shows that you should lift weights in multiple sets for maximum strength gain (J Strength Cond Res, January 2012;26(1):34-39).
A squat means to stand up, place a heavy bar bell on your shoulders, lower your upper body by bending your knees, and then raise yourself up by straightening your knees. The athletes in this study were asked to squat the heaviest weight that they could. This is called the One Repetition Maximum (1RM). They then picked a weight that was 80 percent of their 1RM. The athletes squatted three times a week and were divided into three groups:
• 1 set of 10 repetitions,
• 4 sets of 10 repetitions,
• 8 sets of 10 repetitions.
After six weeks, the athletes doing eight sets of 10 repetitions could squat much heavier weights than those doing fewer sets. Those in the four-set group were not stronger than those in the one-set group.
This shows that you have to damage your muscles to make them stronger. After you do one or two sets of 10, your muscles really start to hurt. If you stop, your muscles usually stop hurting immediately. With each additional set, you increase the muscle damage, and your muscles hurt even more. FOR LIFTING WEIGHTS TO MAKE YOU STRONG, YOU HAVE TO HURT AND REALLY DAMAGE YOUR MUSCLES TO MAKE THEM GROW LARGER AND STRONGER. Of course, you have to know when to stop lifting, because you can pull and tear your muscles if you lift weights that are too heavy for them.
Being Overweight or Diabetic Markedly Increases Your Risk for Cancer
Before insulin can do its job of driving sugar from the bloodstream into cells, it must first attach to hooks on cell membranes called insulin receptors. When fat cells fill with fat, they send out chemicals that prevent insulin from attaching to its receptors. Therefore insulin cannot do its job and blood sugar levels rise too high. This causes the pancreas to release ever increasing amounts of insulin in an attempt to lower high blood sugar levels. Insulin and another hormone called insulin like growth factor 1 (IGF-1) can cause normal cells to become cancerous (Science, January 2012;335 (6064): 28-32). The majority of diabetics and almost all obese people have too much insulin and ILGF-1 and are therefore at high risk for developing cancer.
Furthermore, diabetics who take insulin and drugs that raise insulin levels (such as sulphonylureas) are at even higher risk for cancer. On the other hand, diabetics treated with metformin (Glucophage), a drug that lowers insulin levels, are at lower risk for cancer. Indeed, doctors are working to develop drugs to lower insulin levels to see if they will prevent cancer.
Too Much Vitamin D Can Harm
It may not be safe to take more than 5000 IU of vitamin D per day for a long time. Many people are taking very large doses of vitamin D pills because of the many media reports of low levels of vitamin D being associated with:
• Heart disease
• High blood pressure
• Chronic pain
• Inflammatory Bowel Disease
• Premenstrual Syndrome
• Muscular weakness and pain
• Crohn’s Disease
• Multiple Sclerosis
• Autoimmune diseases
• Falls and muscle weakness
(Maturitas, May 2011;69(1):27-36; Clinical and Investigative Medicine, 12/01/2011;34(6) among many others).
NO BENEFIT FROM HAVING VITAMIN D BLOOD LEVELS ABOVE 75 NMOL/L: In one report, the authors reviewed 14 studies that included 5562 deaths out of 62,548 individuals (Am J Clin Nutr, January 2012;95(1)). They found that as blood levels of vitamin D rie, the death rate drops until it reached 75 to 87.5 nmol/L. After that, the death rate remained the same.
TOO MUCH VITAMIN D MAY INCREASE RISK OF HEART ATTACKS: A blood test called CRP measures inflammation that increases risk for heart attacks. As vitamin D levels rise, CRP levels drop to help protect against heart attacks. However, when blood levels of vitamin D rise above 53 nmol/L, CRP increases (Am J Cardiol, January 2012;109: 226-230).
TOO MUCH VITAMIN D MAY CAUSE ATRIAL FIBRILLATION: All people who develop atrial fibrillation should be asked if they are taking overdoses of vitamin D. If you have an irregular heart beat and are taking large doses of vitamin D pills, check with your doctor immediately. This cause of irregular heart beats can be cured by stopping the pills (Presented at the annual meeting of the American Heart Association on November 16, 2011).
WHAT IS THE SAFE BLOOD LEVEL OF VITAMIN D? The normal range for vitamin D3 is up to 40 ng/ml (equal to 100 nmol/L). You get vitamin D only from sunlight, food and pills. It is impossible to drive vitamin D3 blood levels above 100 nmol/L from sunlight or unfortified food. You can only get toxic levels of vitamin D from pills.
YOU CANNOT GET TOO MUCH VITAMIN D FROM SUNLIGHT. Only a small part of the ultraviolet rays from the sun called UVB makes vitamin D from 7-dehydrocholesterol in your skin. Then vitamin D passes from your skin into your bloodstream. However, UVB also destroys vitamin D in the skin. This effect is so powerful that a person can never get high blood levels of vitamin D, no matter how much sunlight shines on his skin.
YOU CANNOT BE POISONED BY VITAMIN D THAT OCCURS NATURALLY IN FOOD. It is almost impossible to meet your needs for vitamin D from food. The only foods that supply significant amounts of vitamin D are fish, eggs, fortified milk, animal liver and cod liver oil. The only report ever of vitamin D poisoning from food was when people were isolated during a winter in Alaska and their only food was polar bear liver.
THE ONLY BLOOD TEST TO DIAGNOSE VITAMIN D DEFICIENCY IS VITAMIN D3. Do not get calcitriol (1,25 dihydroxy) blood tests to diagnose low Vitamin D. Even in severe vitamin D deficiency, blood calcitriol levels will be normal. Severe vitamin D deficiency causes an overactive parathyroid gland that raises the active vitamin D called calcitriol to normal.
Sports medicine doctor, fitness guru and long-time radio host Gabe Mirkin, M.D., and his wife, nutritionist Diana Mirkin bring you news and tips for your healthful lifestyle. A practicing physician for 50 years more
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