Tumors are gluttons for glucose. They consume this blood sugar at a rate ten to fifty times higher than normal tissues. PET scans, which detect glucose consumption, have shown that the higher the rate of glucose accumulation in cancer cells, the more aggressive the tumor – that is, the more invasive and likely to metastasize it is.
In addition, having high levels of blood glucose – as diabetics do – can make you more susceptible to several different cancers and lead to a worse outcome if you do develop cancer. However, even without diabetes, small elevations in glucose or insulin can wreak havoc on your health and fuel malignancy. Patients who have what’s called pre-diabetes (blood sugar levels that are high but not high enough to be diabetes) or metabolic syndrome (a precursor to type 2 diabetes) have abnormally high blood sugar. They also tend to have elevated levels of insulin because of what is called “insulin resistance.” Insulin is the molecule that transports glucose into muscle, brain and other tissue. In insulin resistance, cells block the entry of glucose. When this happens, blood levels of both insulin and glucose increase in a futile attempt to overcome that resistance.
Insulin, unfortunately, has been shown to promote cancer growth: In a 2002 study, women with early breast cancer who had the highest insulin levels were twice as likely to have their tumor metastasize and three times as likely to die of breast cancer as women with the lowest insulin levels. And a study published in 2005 in the European Journal of Cancer found prostate cancer patients with high insulin levels and metabolic syndrome had shortened survival.
Dr. Block’s Recommendations
Blood sugar spikes, insulin resistance, excess insulin, and IGF-1 production are typically the result of lifestyle and nutritional factors. Make sure you are following the Life Over Cancer recommendations for diet, fitness and mind-spirit wellness (If you are already diabetic and taking medication to control your blood sugar, consult with your treating physician before making any significant changes to your diet and/or supplement program). Here are some of Dr. Block’s additional recommendations:
• Eat frequent, smaller meals instead of three large meals. Frequent, smaller ones will keep your glucose levels steadier, since large meals lead to rapidly increased output of glucose and insulin.
• Improve your sleep. Did you know that sleep deprivation is associated with insulin resistance and diabetes? A 2008 study in the journal Sleep, for instance, found that men who got less than five hours of sleep a night were 50 percent more likely to develop diabetes than those with an average sleep time of seven to eight hours (those who sleep more than nine hours also were more likely to develop diabetes). After inadequate sleep, the body produces higher levels of cortisol and inflammatory biochemicals called cytokines, some of which appear to be responsible for causing insulin resistance.
• Reduce and manage psychological stress. Stress, by raising cortisol levels, provokes insulin resistance and thereby elevates blood sugar. It can also prompt your body to accumulate abdominal fat, a strong risk factor for insulin resistance. There are several recommendations for managing stress and reversing your body’s stress response in Chapter 11 of Life Over Cancer.
• Get regular exercise. Like being overweight, being inactive makes you more prone to insulin resistance and blood sugar imbalances. Since a sedentary lifestyle is a major cause of insulin resistance, engage in 30 minutes of mild to moderate aerobic exercise every day, if at all possible.
• Improve your diet. Avoid refined carbohydrates and substitute high-fiber, low-glycemic –index foods. High fiber diets have been shown to reduce blood insulin levels and may help prevent, if not reverse, insulin resistance.
For more information on The Block Center for Integrative Cancer Treatment, visit BlockMD.com.