After our show last week on lung health, we received a note from a listener about the relationship between estrogen and lung health that alerted us to an article by Dr. Jonathan Wright from his August 2008 newsletter. In it he discusses the work of Donald Massaro and Gloria DeCarlo Massaro, researchers at the Lung Biology Laboratory at Georgetown University School of Medicine.
For over a decade, these and other researchers at the Lung Biology Lab have been investigating the role of estrogen in maintaining lung health. More importantly, they’ve demonstrated that the decline of lung health can be repaired by estrogen therapy.
You’ll remember from last week that alveoli are the tiny sacs in your lungs where oxygen is exchanged for carbon dioxide. As just a matter of physics, lung function improves with smaller and more numerous alveoli. With a lung disease like emphysema, the size of alveoli increases and their numbers decrease in a vicious cycle of oxidative stress. It becomes increasingly difficult to get carbon dioxide out and oxygen in. In addition, the oxidative stress causes the matrix that holds the cells of the alveoli to stiffen, making the lungs less elastic, making breathing more difficult, and adding to the sufferer’s stress.
The chief oxidative stressors that start this process are tobacco smoke, smog, occupational air pollution, and socioeconomic inequity.
One of the common things I found in the literature on this issue is the claim that this restructuring of the lungs is irreversible. According to the Massaros in a review article published in the Proceedings of the American Thoracic Society, this is almost certainly not true. To date they’ve only been able to demonstrate the regeneration of small, numerous alveoli in female mice. However, they argue that there are powerful reasons to believe that humans respond in the same way.
The Massaros note that in humans, the decline of lung function starts in the 30s and 40s for both men and women. For men, the decline is about a 6% loss of capacity per decade. After menopause, a woman’s lung capacity also declines at about the same rate. But before menopause, lung capacity declines at only 2% per decade. The difference? Estrogen. The Massaros cite a number of studies that show how women taking either estrogen or estrogen and progesterone together have better lung capacity than women who do not.
Why would this be so? As Jonathan Wright says in his article, a pregnant woman not only has to eat for two, she has to breathe for two. There’s considerable evidence that estrogen in a healthy female improves the exchange of oxygen for carbon dioxide. For example, comparing male to female mice with similar lung volumes, the females have better respiration capacity.
Why aren’t we hearing about this? Why didn’t I come across it in the research I did for last week’s show?
Even though everything I read echoed the claim that the degeneration of alveoli from lung disease is irreversible, I could not accept that claim. I believe too strongly that the body has an amazing capacity to heal itself—if it’s given what it needs and what it’s used to. On the other hand, what dominates the research literature and the pronouncements from official institutions on lung disease is another ideology, an ideology that views healing as something practitioners do, not the body.
I’m glad I was able to learn this lesson again: bodies heal, sometimes with help from a health practitioner.
