14.1 The Impact of Nutrition on Pulmonary Wellness Across the Lifespan

Pregnancy

Nurses must be skilled in assessing the holistic aspects of client care across the lifespan. One of the critical aspects often overlooked but of incredible value is the nutritional intake of clients. Nurses must comprehend the pulmonary system from pregnancy and infancy to older age, as they assess the dietary aspect and provide education and advocacy for the clients they treat.

As clients progress through the reactions and lifestyle modifications that occur during pregnancy, considering nutrition and how it impacts the pulmonary system is yet another area of importance. Pregnancy elicits various responses from the pregnant client (Dokuhaki et al., 2021). The body undergoes various physiological changes to adapt to the introduction and adjusts to a growing fetus. The pregnant client’s nutritional needs transform to accommodate the developing fetus and consider the client’s physiological changes (Widysanto & Mathew, 2022). Maternal nutritional needs and deficiencies are vital to fetal lung development and prevention of fetal and childhood complications (Arigliani et al., 2018; Baiz et al., 2019; Fandino et al., 2019; Rocha et al., 2021).

Maternal Nutritional Impact on the Fetus

Adequate maternal nutrition prevents intrauterine complications such as intrauterine growth restriction (IUGR) and lung development in the growing fetus (Bendix et al., 2020; Fandino et al., 2019; Voraphani et al., 2022). See Figure 14.2 for the stages of lung development. IUGR results from below-average fetal development and equates to babies that are small for gestational age and have an abnormal growth trajectory; it is linked with placental dysfunction and malnutrition. The term IUGR is often interchanged with small for gestational age (SGA), but the terms vary in that SGA means the fetus is small for gestational age but has an average growth trajectory. The clinical definition of IUGR is a baby weighing less than two standard deviations below the mean or remaining below the tenth percentile at a specified gestational age (Bendix et al., 2020). Infants with IUGR are at risk for complications such as asphyxia, hypothermia, hypoglycemia, and polycythemia. Long-term complications include growth limitations, neurodevelopmental handicaps, and disease processes linked to the cardiovascular, renal, and immunological systems. Even if the growth occurs in incremental units, the fetus may experience IUGR or meet poor outcomes from maternal malnutrition (Arigliani et al., 2018; Fandino et al., 2019; Rocha et al., 2021).

Figure 14.2 Fetal lung development occurs in distinct phases during different weeks of gestation. When development is complete the fetus is prepared for breathing that takes place outside of the womb. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

If a pregnant client has inadequate nutrition, the infant with IUGR is at a higher risk for reduced nutrient availability and oxygen related to placental insufficiency. Undernutrition during pregnancy leads to impaired alveolarization and suppressed surfactant protein expression, diminished pulmonary vascular development, lower alveolar surface area, increased extracellular matrix, and thickened blood-gas barrier, limiting compliance and capacity. Causes of IUGR include severe maternal starvation and suppressed pregnancy weight gain, high altitude, maternal hypoxia, diabetes, and infections such as tuberculosis. Inadequate protein intake during pregnancy leads to embryonic losses, IUGR, and reduced postnatal growth, leading to a deficiency in amino acids critical for cellular metabolism and function (Herring et al., 2018). In contrast, high protein intake during pregnancy may also cause IUGR and embryonic death related to amino acid excess and ammonia toxicity (Herring et al., 2018). Nurses must assess and educate the pregnant client on the importance of moderate protein consumption. The recommended protein intake for the first trimester is 46 g/day and increases to 71 g/day during the second and final trimesters (Murphy et al., 2021).

Infancy

Infancy is a stage that begins the lifespan. It follows pregnancy and birth and is characterized by rapid growth, development, and adaptations. During infancy, the baby experiences rapid weight and height gains. Generally, depending on the source, babies are considered infants from birth up to age 1. Cognitive development during infancy includes exploration, attention, memory, inquisitiveness, and communication acquisition. An infant’s milestones include holding their head up, rolling over, sitting with support, crawling, standing, and walking. Infants form bonds with their caregivers that are shared through eye contact, touch, responsive care, and body language. Infants rely on their parents or caregivers for full support.

The pulmonary system undergoes significant adaptations to support the transition between the in-utero and outside world. The fundamental pulmonary changes include the lungs’ transition from fluid-filled to breathing outside air (Arigliani et al., 2018; Fandino et al., 2019; Rocha et al., 2021). Surfactant production increases late in pregnancy and continues through development and maturation during the first few weeks of life. The lungs can expand and stretch, allowing for growing volume capacity. The airways continue to grow and mature. Infants obtain antibodies through breast milk in colostrum (in the first few days of life) and immunoglobulin A (after the first few days) to help infants fight infection and support their immune systems.

Childhood

Alveolarization continues from infancy through approximately 8 years of age. Even if pulmonary development and function is normal at birth, insulting exposures can cause setbacks. Some scientists have traced poor lung function from infancy through childhood to identify potential events associated with decreasing optimal pulmonary development and capacity. A child born without any difficulty in pulmonary function but exposed to second-hand smoke may experience stunted growth (Schultz et al., 2018). According to Schultz et al. (2018), in the same study, when individuals demonstrated limitations at age 8 in lung function, they maintained these lower levels of function even when retested at age 16. When 8-year-old children have developmental limitations and are exposed to second-hand smoke, their lung function diminishes. Maternal smoking habits throughout pregnancy also play a role in decreased lung development. Schultz et al. (2018) study results further support the view that being born prematurely increases the risk for diminished lung development and function as the child grows. These children do not recover the lost development with age. They also are at an increased risk for developing asthma, wheezing, and declination of lung function during respiratory infection season.

Adolescence

Childhood progresses into the adolescence stage through physiological alterations (Han et al., 2019; Schultz et al., 2018). These changes include increased lung volume, respiratory muscle strength, airway resistance, susceptibility to respiratory tract infection (RTI), and decreased respiratory rate, as follows:

• Lung volume increases as the child grows. The lung capacity and volume continue to grow as long as there are no underlying factors hindering growth (Schultz et al., 2018).
• Increased respiratory muscle strength continues, and muscles increase the ability to exchange air in the lungs.
• Increased airway resistance occurs because of functional and structural changes during adolescence.
• Increased susceptibility to respiratory infections occurs as changes to the immune system and lack of adequate nutritional intake influence.

Overall, the physiological changes that occur during adolescence contribute to or deter from pulmonary capacity and function. Although RTI susceptibility increases and asthma can be challenging during adolescence, the pulmonary systems of most adolescents experience growth.

Nutritional intake during adolescence is crucial as the pulmonary system grows and develops (Gozzi-Silva et al., 2021). Adequate macronutrient and micronutrient intake also aids in the immune system’s development. Protein consumption should include 0.85–1.2 g of protein per kilogram of body weight per day (Hudson et al., 2021). Solid recommended sources of protein include lean meats, poultry, fish, eggs, dairy products, beans, tofu, legumes, and nuts.

Micronutrient intake for adolescents should focus on vitamins A, C, and E, omega-3 fatty acids, magnesium, and water (Gozzi-Silva et al., 2021; Scoditti et al., 2019). Vitamins A, C, and E are essential antioxidants that protect the lungs from oxidative stress and inflammation. See Table 14.1 for a list of vitamins and possible food sources. Finally, adolescents must remain hydrated, which is essential for all life functions.

Diets full of fruits, vegetables, whole grains, lean proteins, and healthy fats all regulate the development of lung tissue and repair, promoting a healthy immune system. In addition to these specified nutrients, adolescents need to consume a balanced and varied diet (Gozzi-Silva et al., 2021) and exercise regularly to support proper pulmonary function.

Adulthood

Adulthood is a developmental stage after adolescence and typically lasts until later adulthood. During this period, individuals reach physical and cognitive maturity and assume adult responsibilities, such as career development, marriage, and parenthood. Fewer physiological changes occur as the state of health stabilizes, and fewer rapid developmental changes occur. The body does gradually change in function and structure during the aging process. Some of these changes occur in the pulmonary system, so it is vital for nurses to advocate for healthy lifestyle modifications and perform regular health screenings to promote optimal pulmonary health throughout adulthood.

The physiological changes during this time include lung size and function, respiratory muscle strength, respiratory diseases, immune function, and lifestyle habits (Han et al., 2019; Schultz et al., 2018; Rogers & Cismowski, 2018). By adulthood, lung growth and development are maximized, and function begins to decline. Respiratory muscle strength improves during adolescence but declines as one ages. In adulthood, respiratory disease risk increases related to unhealthy lifestyle choices such as smoking, occupational exposure (chemical plant workers, construction workers, and health care providers exposed to chemicals such as chemotherapy), and not exercising. The immune system protects the respiratory system as one of its functions from infection and inflammation. When a client reaches adulthood, immune function diminishes gradually, making individuals more susceptible to illnesses throughout aging.

Later Adulthood

As people age, their progression parallels their risk for chronic disease. The lungs experience physiological changes as people age, leading to altered lung capacity and increased risk for infection. The lungs also suffer a barrage of continuous assaults over their lifetime. These assaults are chemical, mechanical, biological, immunological, and xenobiotic. These insults lead to oxidative stress in the lung tissue because of antioxidant capacity depletion.

Free radicals are unstable molecules that contain unpaired electrons in an atomic orbit that participate in phagocytosis's cellular destruction mechanism through macrophages and granulocytes (Sharifi-Rad et al., 2020). Phagocytosis is the process of phagocytes ingesting and eliminating larger particles. Free radicals are kept at bay by the body’s antioxidant system. Adverse effects occur when homeostasis of the free radicals is not maintained. Research studies indicate the free radicals of oxygen play a role in chronic disease and deoxyribonucleic acid (DNA) damage (Sharifi-Rad et al., 2020). Increasing the amounts of free radicals cause cellular damage and apoptosis (the death of cells). Antioxidants counteract the free radical destruction process.