Strategies for Optimal Pulmonary Function
By Jason E. Barker, ND
Breathing, for most people, is perhaps one of the most effortless acts we do to sustain life. The respiratory system functions with very little conscious effort; our breathing rate increases and decreases based on the body's demand for energy. Oxygen is the catalyst that drives our energy production systems. A continuous oxygen supply and the removal of wastes (namely carbon dioxide) are perhaps the most vital of all physiological processes because life can only be sustained 4 to 6 minutes without oxygen, when the brain will become permanently damaged. Beyond this time, death rapidly ensues.
The average person breathes about 12 times per minute at rest. Put another way, respiration occurs 720 times per hour, 17,280 times per day and 6,307,200 times per year (keeping in mind these numbers reflect a resting state.) At this rate, a person will inhale roughly 7 or 8 liters (depending on his or her size) of air in a minute or 11,000 liters per day.
In order to absorb enough oxygen, the lungs maintain an incredibly large surface area. Comprised of roughly 300 million tiny air sacks called alveoli, the total surface area of the lungs is thought to be over 1,700 square feet or 80 times the skin's surface area.
Just as important as the uptake of oxygen, the lungs remove wastes from our body. Carbon dioxide is the primary gas exhaled by the lungs; other gases from a variety of metabolic processes are exhaled as well. Just as oxygen intake is vital, the inability to remove carbon dioxide causes major health issues as well.
The alveoli are very small, thin-walled (one cell layer thick) sacks into which air flows in and out. An intricate network of capillaries surrounds every single alveolus. The capillaries are the smallest blood vessels in the body; their walls are also only one cell layer thick and their diameter is so narrow it only allows for red blood cells to pass single file.
All the blood vessels in the body eventually lead to the lungs, where the capillaries deliver de-oxygenated, carbon-dioxide rich blood. At the alveoli, carbon dioxide diffuses from the blood into the alveoli, where it is then exhaled. At the same time, these same capillaries pick up oxygen from and deliver it to the rest of the body. Both oxygen and carbon dioxide are transported via the red blood cells; the balance continually shifts as each molecule is released or added to the red blood cell.
Impaired Lung Function
The lungs, like any other organ, are susceptible to several types of diseases. These diseases affect three main anatomical areas of the lung: airways, lung tissue and pulmonary (lung) circulatory system.
Airway diseases affect the movement of air in and out of the lungs. “Airway” is a common term used to describe the tubes through which gases are transported into and out of the lungs. The trachea is the main, largest airway; it divides into smaller tubes known as bronchi and they divide into even smaller tubes known as bronchioles.
Some of the most common airway diseases include asthma, bronchitis and emphysema.
Asthma occurs when the small muscles surrounding the bronchioles constrict. This constriction “strangles” the bronchioles, limiting air movement in and out of the lungs. Asthmatic constriction can occur from any number of factors; some of the most common include exercise, cold air, environmental pollutants and allergens. Asthma also has an inflammatory component: cells of the immune system infiltrate the lung tissues, creating even more constriction of the lungs. Reducing airway inflammation is a key target of asthma therapy.
In emphysema, the structure of the alveoli deteriorates. The walls between each alveolus break, creating larger sacks in which air becomes trapped. This decreases the lung's surface area, reducing the area available for gas exchange. As the alveoli lose their shape and function, air becomes trapped in the damaged alveoli and cannot move out of the lung. The main cause of emphysema is cigarette smoking, although there are other more rare causes such as alpha-1 antitrypsin deficiency.
Chronic bronchitis is defined by chronic inflammation of the bronchi.
These medium-sized airways are always inflamed, which creates excessive production of mucus and swelling, limiting the passage of gases in and out of the lungs. The main cause of bronchitis also is cigarette smoking.
Emphysema and chronic bronchitis are also known as chronic obstructive pulmonary disease or COPD.
Lung tissue diseases, such as pulmonary fibrosis and sarcoidosis, affect lung tissue structure. These conditions cause the lungs to become scarred and inflamed, preventing them from expanding to allow for air intake and gas exchange. In pulmonary fibrosis, the lung tissue grows thicker and becomes stiff. Sarcoidosis can occur anywhere in the body, but in the lung collections of inflammatory cells coalesce into nodules known as granulomas. This condition also makes the lung tissue less pliable and limits the exchange of gases.
Pulmonary circulatory diseases affect the blood vessels traveling to and from the lungs, as well as those inside the lungs. In these conditions, pulmonary blood vessels become scarred and inflamed, and clots can occur leading to lung tissue destruction. Pulmonary circulatory diseases may also directly affect the heart by exerting pressure back towards the heart; this is known as pulmonary hypertension.
All of these diseases affect the lungs' primary purpose of gas exchange in different ways. Primarily, less oxygen can be taken up, while waste gases such as carbon dioxide are allowed to buildup in the blood stream. Each disease has many subcategories and levels of complexity.
Natural Support for Lung Health
In addition to standard medical treatment for lung diseases, several natural compounds can help maintain pulmonary health.
Quercetin, bromelain and vitamin C (all found in Histamine Balance®) can provide synergistic lung support. Quercetin is a plant-derived flavonoid compound found primarily in the skins of fruits and leaves. It has been studied extensively for its anti-inflammatory1-2 and antioxidant properties.3 Several animal studies show a pronounced anti-inflammatory effect of quercetin in the lungs.4 Quercetin was shown to reduce areas of fibrosis and collagen (a connective tissue protein) deposition, as well as levels of a common inflammatory protein (TGF-beta-1) in an experimental model of pulmonary fibrosis.5 The antioxidant and anti-inflammatory effects of quercetin make it ideal for adjunctive lung support for lung issues in which oxidation is a major component.6
Bromelain is an anti-inflammatory enzyme derived from pineapple. Bromelain stimulates the production and release of anti-inflammatory prostaglandins (PGs), while simultaneously reducing the production and release of proinflammatory PGs.7
Vitamin C is one of the key antioxidant vitamins abundant in the extracellular fluid lining the lung. Low vitamin C intake has been associated with pulmonary dysfunction.8
Oxidation and inflammation are major pathogenic (disease-causing) factors in chronic lung diseases.9 Providing a means to limit the destructive inflammatory and oxidative processes should be a major component of lung care. Glutathione is one of the body's major antioxidants. In the lungs, glutathione plays an especially important role as it is found in high concentrations and when depleted, is associated with an increased risk of damage and disease in the lungs.10-11 When delivered in a supplemental form, glutathione, like all antioxidants, is quick to react with oxidative molecules making it somewhat unstable. New technology now makes glutathione “encapsulated” in a minute chamber known as a liposome. Liposomal glutathione, as it is known, is more stable and gains easier entry into the cells where it is needed.12
N-acetyl cysteine (NAC) is a derivative of the amino acid cysteine. It has two very useful functions in the lungs; the first being it is a direct precursor to glutathione, effectively boosting its levels in the lungs where it is needed. Second, NAC is also an effective mucolytic (substance that breaks down mucus).13 NAC may be helpful in lung conditions in which increased mucus production is common, such as COPD.14 NAC can also inhibit the functions of an inflammatory protein (TGF-beta-1) that plays a role in COPD, idiopathic pulmonary fibrosis and asthma.15
The lungs perform such important life-giving functions, yet we rarely notice how effortless they work until disease occurs. There are many lung diseases; however, their common effect is to impede the exchange of gases that we depend on for life. Protecting the lungs with natural compounds such as quercetin, bromelain, vitamin C, liposomal glutathione and NAC, which provide anti-inflammatory, antioxidant and mucolytic functions, can help support lung health.
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