Lung Function and Longevity: Is There A Correlation?

Lung capacity, or the amount of air that can be inhaled and exhaled, has been shown to have a significant impact on longevity. Studies have found that people with higher lung capacity tend to live longer than those with lower lung capacity.

The lungs play a vital role in the body's ability to oxygenate the blood and remove carbon dioxide.

When the lungs are functioning optimally, they can efficiently transfer oxygen from the air we breathe into the bloodstream, where it is then transported to the body's cells and organs.

This process is essential for maintaining good health and preventing disease.

However, when the lungs are not functioning well, the body is not able to efficiently oxygenate the blood, and this can lead to a host of health problems, including heart disease, stroke, and respiratory illness.

Similar to other parts of your body, your lung function declines with age.

Typically, your lungs finish development by age 25, and their function remains stable for about 10 years. Thereafter, they begin to gradually decline and by age 65, you have typically lost up to a liter of lung capacity compared with when you were younger.

The lungs in action

Upon inhalation, air flows into the lungs to fill tiny air sacs. Blood circulates around these air sacs through small blood vessels. The point where the blood vessels and air sacs meet is also where oxygen moves into the bloodstream and carbon dioxide passes out of the blood to be exhaled.

Aging cause both the airways and blood vessels to become stiffer, and the air sacs expand, making it more difficult for gases to move into the bloodstream. This typically results in getting more winded doing everyday activities, like walking a short distance or climbing a small flight of stairs.
 
Factors that can accelerate your lungs’ aging include smoking, exposure to air pollution, and repeated respiratory infections. Quitting smoking is without a doubt the best way to help your lungs’ health.

But there are other variables that can affect lung function.

For instance, bones can become thinner as you age, which can lead to osteoporosis and changes in posture that make your chest cage smaller and stiffer. This makes it more difficult for your chest to fully expand when breathing and reduces the volume of air your lungs can hold. Another factor that plays a big part in breathing mechanics is your diaphragm. The diaphragm can weaken with age and prevent you from taking in full breaths.

Research-based evidence

Results from several studies indicate a significant relationship between pulmonary function and both all-cause mortality as well as cause-specific mortality (i.e., ischemic heart disease mortality) [1].

Pulmonary function was assessed from the Forced Expiratory Volume in one second (FEV1) which is the amount of air you can force from your lungs in one second.

It is measured during a spirometry test, also known as a pulmonary function test, which involves forcefully breathing out into a mouthpiece connected to a spirometer machine.

It has been suggested that the observed association between pulmonary function and mortality may be explained by smoking status [2].

However, prominent studies reported that FEV1 to be a risk factor for mortality independent of smoking status and other studies have found the association also in non-smokers [3].

An important landmark study conducted at the University of Buffalo investigated the association between pulmonary function and mortality for periods that extended past 25 years, which was the limit of previous studies [4].

This was a prospective study with a 29 year follow up.

Participants were a randomly selected sample of 554 men and 641 women, aged 20 to 89 years. Baseline measurements of FEV1 were performed in 1960 and 1961.

Findings from this study indicated that FEV1 is a risk factor for all-cause and for ischemic heart disease mortality for a follow-up period of 29 years after adjusting for other risk factors.

These results are pretty startling:

• Researchers found that 20% of men with the poorest lung function upon the start of the study were more than twice as likely to have died during follow-up than men with the best lung function.
• Women in the lowest group were more than 1 ½ times more likely to have died.

Results of this research confirm previous reports that pulmonary function is an independent risk factor for overall all-cause mortality and ischemic heart disease mortality and suggests that this risk is evident for longer periods than what research has shown to this point.
 
Another long-term study called the Framingham Heart Study found a strong association between efficient breathing and a longer life span.

In this study, a cohort of 5,209 men and women were followed for more than 20 years. Each was evaluated for Forced Vital Capacity (FVC) which is simply the amount of air you can forcibly exhale from the lungs after taking the deepest breath possible. FVC was a strong predictor of cardiovascular-related death and disease.

Mechanisms of action

The mechanism for this is not entirely clear. The lung is a primary defense organ against environmental toxins, and impaired pulmonary function could lead to decreased tolerance against these environmental toxins. Oxidative stress, which influence FEV1 and health status, might be responsible for the observed relationship [5].

In fact, oxidative stress is known to play a role in the etiology of various diseases, including ischemic heart disease [6].

In addition, it’s been demonstrated that indicators of oxidative stress are negatively correlated with FEV1.

In support of this, other research demonstrates a positive correlation between antioxidant vitamins and respiratory function [7], but it’s noted that reduced pulmonary function also could be the underlying factor responsible for increased oxidative stress [8].

More research is needed to investigate if oxidative stress is related to both pulmonary function and mortality.

Inflammation may be an underlying cause of the oxidative stress that plays a role in diseases.

Inflammaging describes a chronic, low-grade inflammation that occurs in the elderly, even in the absence of immunologic threat from pathogenic infection. The inflammation is characterized by systemic increases in levels of inflammatory cytokines (i.e.., IL-1β, IL-6, IL-8 and TNF-α) and oxidative stress.

Inflammaging involves the sustained activation of the innate immune system and the gut microbiota of the elderly [9]. This dysregulation of inflammatory cytokine networks in the older population increases their susceptibility to lung injury and results in a far more exaggerated inflammatory response than would occur otherwise in younger individuals.

Steps to preserve lung function

Although the deterioration of lung function occurs with aging, there are things that we can do to mitigate these decrements and maintain healthy lungs as we age. Below are a few things that will help with lung function as we age:

• Practice taking deep breaths. medical studies demonstrate that practicing incentive spirometry on a daily basis for approximately 5-6 weeks significantly improve both lung capacity and lung function, including vital capacity, maximal dynamic pressure, maximal expiratory pressure, and general inspiratory muscle performance. Incentive spirometry essentially is training the respiratory muscles using various mechanical aids, especially those that offer visual feedback (e.g. disposable spirometer)
• Eat fruits & vegetables. Research indicates that the intake of fruit and vegetables directly improves breathing, including general lung function, FEV1 and forced vital capacity. Apples (which contain high levels of the antioxidant quercetin) and vitamin E appear to have a particularly strong positive effect on lung function. Red onions, blueberries, red grapes, raspberries, and other various berries also contain high concentration of quercetin.
• Don’t wear tight clothes. Clothing that restricts movement of either the abdomen or the rib cage increases resistance, creating external loading of the system. Restrictive clothing can significantly inhibit breathing, and decrease vital capacity, FEV1, and forced vital capacity.
• Take big breaths, even when you don’t think you need them. Research indicates that expiring at high lung volumes (that is, blowing out after taking a large breath) requires less force and fewer overall muscles than at lower lung volumes. This benefit of elastic recoil in expiration decreases in an approximately linear manner with lung volume. In other words, the less air you have in your lungs, the more effort it requires to expel a given amount of air.
• Exercise. Regular physical activity can help to increase lung capacity and improve overall lung function. This can be done through cardio exercises such as running, swimming, cycling, and others.

Summary

Overall, lung capacity is a critical factor in determining longevity. By taking steps to improve lung function, such as quitting smoking, exercising regularly and keeping a healthy lifestyle, we can help to ensure that our lungs are able to function at their best and increase our chances of living a long and healthy life.

One suppplement has been shown to improve the body's total antioxidant capacity and reduce oxidative stress.

It's called CoQ10, and not only is it effective at improving the body's antioxidant capacity, it's also been shown to improve heart health too.

References:
1.    Hole, D.J., et al., Impaired lung function and mortality risk in men and women: findings from the Renfrew and Paisley prospective population study. BMJ, 1996. 313(7059): p. 711-5; discussion 715-6.
2.    Marcus, E.B., et al., Pulmonary function as a predictor of coronary heart disease. Am J Epidemiol, 1989. 129(1): p. 97-104.
3.    Bang, K.M., et al., The effect of pulmonary impairment on all-cause mortality in a national cohort. Chest, 1993. 103(2): p. 536-40.
4.    Schunemann, H.J., et al., Pulmonary function is a long-term predictor of mortality in the general population: 29-year follow-up of the Buffalo Health Study. Chest, 2000. 118(3): p. 656-64.
5.    Weiss, S.T., et al., Relation of FEV1 and peripheral blood leukocyte count to total mortality. The Normative Aging Study. Am J Epidemiol, 1995. 142(5): p. 493-8; discussion 499-503.
6.    Cross, C.E., et al., Oxygen radicals and human disease. Ann Intern Med, 1987. 107(4): p. 526-45.
7.    Dow, L., et al., Does dietary intake of vitamins C and E influence lung function in older people? Am J Respir Crit Care Med, 1996. 154(5): p. 1401-4.
8.    Schunemann, H.J., et al., Oxidative stress and lung function. Am J Epidemiol, 1997. 146(11): p. 939-48.
9.    Oishi, Y. and I. Manabe, Macrophages in age-related chronic inflammatory diseases. NPJ Aging Mech Dis, 2016. 2: p. 16018.
10.    Schuliga, M., J. Read, and D.A. Knight, Ageing mechanisms that contribute to tissue remodeling in lung disease. Ageing Res Rev, 2021. 70: p. 101405.