Life Extension Magazine November 2010
The Drug Virtually Everyone Should Ask their Doctor About
By Julius Goepp, MD
More men and women die from lung cancer than from any other malignancy. In 2006, lung cancer caused more deaths than breast cancer, colon cancer, and prostate cancer combined.51 Clearly, new solutions to fighting lung cancer are greatly needed. Emerging research suggests that metformin may offer hope in combating this deadly disease.
In a recent study, scientists examined the effects of metformin on an experimental form of lung cancer that is especially aggressive in obese subjects with high blood sugar. Animal subjects received either a control diet or a high-energy diet that typically leads to weight gain and insulin resistance, and selected subjects received metformin in their drinking water. After three weeks, the subjects were injected with lung cancer cells. Seventeen days later, animals on the high-energy diet had tumors that were twice the volume of animals on the control diet. Metformin significantly attenuated tumor growth in subjects consuming a high-energy diet. Metformin led to increased phosphorylation of AMPK and attenuated the increased insulin receptor activation association with a high-energy diet—both of which would be expected to decrease cancer proliferation.3
Additional research suggests that metformin may enhance the effects of radiation therapy in eradicating lung and other cancers.52
While further studies are needed, these findings suggest that metformin may offer promise in the fight against lung cancer.
The list of cancers against which metformin is protective is growing rapidly, now including cancers of the prostate, pancreas, liver, lung, and other tissues.3,16,95,96 Since metformin acts by multiple pathways, most of which are fundamental to every kind of cancer, there’s no reason to think that these results won’t in fact be generalizable to every human malignancy.
The key fact about metformin is its ability, shared with other nutraceuticals but rare among other prescription drugs, to potently mimic the effects of calorie restriction. Metformin’s calorie restriction-like effects trigger profound cellular changes in every mammalian tissue, activating tumor suppressing mechanisms while suppressing tumor activating mechanisms. By lowering chronic blood sugar levels and limiting lifetime exposure to insulin and insulin-like growth factors, metformin can directly reduce cancer risks related to these factors.
The wealth of evidence of metformin’s anti-cancer activity is now expanding to include not only those with diabetes or pre-diabetic conditions, but also people who are apparently otherwise healthy. This means that anyone who is serious about a comprehensive approach to cancer prevention should give serious consideration to using metformin just as faithfully as they use other calorie restriction-mimetic supplements.
Those seeking to gain the longevity benefits associated with reduced glucose and insulin levels can benefit tremendously from metformin.
As you read in last month’s issue, optimal fasting glucose should be around 80 mg/dL. Metformin can help aging humans achieve these lower and healthier glucose levels. Typical doses are 250 mg to 850 mg taken before two or three meals each day. Refer to the box on the following page for information about who should not take metformin.
If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.
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