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Will Diabetes Drug Metformin Also Help Your Lungs?

The diabetes drug metformin is showing promise in treating some unrelated but serious conditions, including pulmonary fibrosis, thyroid nodules and certain cancers.
Metformin is an oral antidiabetic drug in the biguanide class. It is the first-line drug of choice for the treatment of type 2 diabetes. 3d illustration

Metformin is a very old drug that is used to treat type 2 diabetes. It was developed from the French lilac plant, Galega officinalis. Healers in the 17th century used extracts from this plant to treat symptoms associated with type 2 diabetes. The diabetes drug metformin was first used as a medication in France in 1957. It is one of the most widely prescribed drugs in the world for this metabolic disorder. Now, however, scientists are discovering that the diabetes drug metformin may also benefit a range of other health problems.

Could Diabetes Drug Metformin Benefit Pulmonary Fibrosis?

Researchers have now discovered that metformin may have other health benefits. Scientists at the University of Alabama at Birmingham report that the drug appears to be helpful in models of pulmonary fibrosis (Nature Medicine, July 2, 2018).

This condition affects over 150,000 people each year and it can be fatal. The small air sacs called alveoli become scarred and stiff as a result of a repair process that goes awry. Pulmonary fibrosis can be triggered by certain medications, cancer chemotherapy, radiation or infection. Environmental toxins such as silica or coal dust, asbestos fibers and bird droppings may also contribute to fibrosis. Treatment is difficult, and there is no cure available at this time.

If the preliminary research with metformin holds up in clinical trials, however, this ancient medicine might become a breakthrough for reversing pulmonary fibrosis.

Diabetes Drug Metformin May Also Protect the Thyroid:

Metformin holds promise for certain other conditions in addition to diabetes and pulmonary fibrosis. It is also being studied for its ability to prevent the development of certain cancers. One reader wrote about a somewhat unexpected benefit of taking the diabetes drug metformin.

Does the Diabetes Drug Metformin Control Thyroid Nodules?

Q. My endocrinologist has prescribed the diabetes drug metformin to control thyroid nodules and prevent thyroid cancer. I am not diabetic, so my other doctors wonder why I would be taking metformin. Is there any evidence that metformin has anticancer benefits?

A. Your endocrinologist is keeping up with medical research. A review in the journal Frontiers in Endocrinology (Nov. 14, 2017) discusses the anticancer activity of metformin, particularly with respect to thyroid cancer.

There is also evidence that this drug can reduce thyroid nodules and may both prevent and help treat thyroid cancer. A systematic review concluded that metformin might be helpful in treating colorectal and prostate cancer as well (Coyle et al, Annals of Oncology, Dec, 2016).

Metformin Has Role in Cancer Prevention:

Scientists have been studying exactly how metformin can reduce the risk of various types of cancer. They are also considering how it might be used in conjunction with more conventional therapies to treat certain cancers (Morales & Morris, Annual Review of Medicine, 2015). In addition to colorectal and prostate cancers, researchers suggest that its ability to keep cancer cells from proliferating could be valuable in treating lung cancer (Gupta et al, Panminerva Medica, online Jan. 25, 2018). They are even evaluating its usefulness in helping to treat glioblastoma multiforme, an aggressive brain cancer (Valtorta et al, Oncotarget, Dec. 2017). This medication suppresses cancer stem cells, including those from pancreatic, breast, colon and prostate cancers (Saini & Yang, Acta Biochimica et Biophysica Sinica, online Oct. 7, 2017).

The Diabetes Drug Metformin Reduces the Risk of Head and Neck Tumors:

Researchers have reported that metformin may also offer benefits against head and neck tumors (Curry et al, The Laryngoscope, Aug. 2017). In this pilot study, the researchers took tissue samples from 39 patients with head or neck tumors. The participants then took metformin at about half the dose used by people with diabetes. The scientists sampled the tumors again and compared the metabolic markers.

How Does Metformin Fight Cancer?

Metformin interferes with cancer cells’ ability to create energy for growth by changing the pathways they use. Cancer cells are fast-growing, so they need a lot of energy generated quickly. The medication also encourages cancer cell death by disrupting the cancer-support system. Because metformin is generally well-tolerated and far less toxic than standard cancer drugs, it may become a valuable adjunctive treatment for a variety of tumors.

We have written previously about the diabetes drug metformin being used to fight cancer. You can read about it here and here.

Other Readers’ Experience:

Keep in mind that risk reduction is based on statistics. Nothing that we know of prevents cancer in everybody.

Everett wrote of his disappointment:

My dermatologist just did a full-body inspection and found a squamous cell cancer on my forehead. I’ve been taking metformin for two years, so in my opionion, its anticancer activity is overrated.”

Lyn cautioned:

Metformin does have negative side effects for some people. Be sure to check with your physician in light of your own medical history before you jump into taking it.”

You can read more about metformin side effects and how to overcome them here. If you have had experience taking the diabetes drug metformin to prevent or treat cancer, please tell us about it in the comment section below.

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About the Author
Terry Graedon, PhD, is a medical anthropologist and co-host of The People’s Pharmacy radio show, co-author of The People’s Pharmacy syndicated newspaper columns and numerous books, and co-founder of The People’s Pharmacy website. Terry taught in the Duke University School of Nursing and was an adjunct assistant professor in the Department of Anthropology. She is a Fellow of the Society of Applied Anthropology. Terry is one of the country's leading authorities on the science behind folk remedies. .
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My respiratory Physician has not observed any benefits to the lungs in his patients on metformin.

Metformin is absolutely great, but people with weak kidneys should reduce metformin’s use or consider stopping using it. Consult a nephrologist, possibly online.

Since Metformin lowers blood glucose which is known to be a stimulus for inflammation I wonder whether Berberine or organic apple cider vinegar both of which have positive hypoglycemic effects may also help with the listed medical conditions. Also Dr. Warburg showed 3/4ths of a century ago that cancer cells need to be almost spoonfed their glucose to survive and will commonly die off when an individual goes on a ketogenic diet. Once again simple carbs and sugar are bad for us. What do you think? Charles, ……..MD, Internal and Integrative Medicine.

Thought you might want to see this article on metformin…

Metformin can cause depletion of Vitamin B-12 levels in the body which can lead to confusion/dementia and neurological problems. I am convinced that this is what killed my friend two years ago when she fell, hit her head, and experienced a severe brain bleed.

She had been taking metformin for several years and was experiencing dementia in the form of short term memory loss, confusion, and problems with her gait and balance, falling frequently. None of her doctors could explain the cause of her problems, and none of them, not even the specialist who gave her a neuro-psych exam, ever tested her B-12 levels.

This is a commonly prescribed drug, but doctors need to be more aware of its possible side effects.

My friend, who experienced short term memory loss, confusion, and neurological problems that affected her balance and gait, causing her to fall frequently, was taking metformin for several years.

When she began experiencing these problems no one could explain why. She was even referred to a specialist for a neuro-psych examination, and the doctor could not explain the type or cause of the dementia and other problems.

My friend fell, hit her head, and died within hours from a severe brain bleed two years ago.

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