Amber Berlin

Every year at Thanksgiving we gather around the table and consume massive amounts of turkey. Then we spend the afternoon napping on the couch in a turkey coma. We know from experience that turkey is a food that promotes a state of sleepiness, and we also know that you wouldn’t want to eat that same turkey dinner and embark on a flight requiring you to be awake and alert. But why does the turkey dinner cause us to get sleepy? And what other foods can contribute to being too sleepy when you need to fly, or too awake when you need to sleep? In an effort to provide a complete understanding of why these foods work like they do, let’s get started on the main course: an easily digestible neuroscience lesson.

Understanding The Best Diet For Pilots

The body must gain certain nutrients from the diet, and these nutrients keep the body and mind performing at maximum efficiency. There are 9 essential amino acids that we must obtain from our diet in order to stay healthy (Young, 1994). All of the other amino acids required by the body can be produced from these 9 essential amino acids. Any lack of nutrients will have a direct impact on how the body and mind function, creating an environment which is detrimental to its recovery. Of the chemicals consumed by our body in the foods we eat, the following four chemicals play a significant role in achieving a state of sleep or wakefulness:

Tyrosine – a non-essential amino acid produced inside the body from Phenylalanine. Tyrosine contributes to an increased state of alertness and wakefulness in the brain.

Tryptophan – an essential amino acid found in most protein. Tryptophan has the ability to increase brain levels of serotonin, which produces a relaxed, calm state.

Serotonin – Biochemically derived from Tryptophan, Serotonin is primarily found in the gastrointestinal (GI) tract, platelets, and in the central nervous system (CNS) of humans and animals. It is a well-known contributor to feelings of well-being.

Dopamine – a catecholamine neurotransmitter present in a wide variety of animals…in the brain, this phenethylamine functions as a neurotransmitter, activating the five types of Dopamine receptors—D1, D2, D3, D4, and D5—and their variants. Dopamine has many functions in the brain, including important roles in behavior and cognition, voluntary movement, motivation, punishment and reward, inhibition of prolactin production (involved in lactation and sexual gratification), sleep, mood, attention, working memory, and learning.

Because of the chemical composition of foods and the way the body metabolizes these foods, eating a certain diet can either create a state in the body which promotes wakefulness or sleep. If you have a busy duty day ahead of you, it makes sense to indulge in the foods that support a state of wakefulness. However, if it’s the end of your duty day and you need to relax, it makes sense to consume those foods which promote sleep.

Foods That Increase a State of Wakefulness

High protein/low carbohydrate meals increase Tyrosine in the brain. Foods high in the essential amino acid Phenylalanine include:

• Soy Foods, Soy-based Protein Powder
• Parmesan and Swiss Cheese
• Peanuts, Almonds, Sunflower Seeds
• Lean Beef, Lamb, Chicken, Turkey
• Tuna, Lobster, Salmon, Mackerel, Crab, Halibut, Cod
• White Beans, Lentils, Chickpeas
• Wild Rice, Brown Rice, Quinoa, Oats, Oat Bran, Wheat Bran
• Gelatin
• Milk

Dopamine is also derived from the essential amino acid Phenylalanine and contributes to wakefulness. Dopamine is easily oxidized and foods rich in antioxidants, such as fruits and vegetables, may help protect dopamine-using neurons from free radical damage. Sugar, saturated fats, cholesterol, and refined foods contribute to low levels of dopamine.

Foods That Increase a State of Sleepiness

The essential amino acid Tryptophan promotes increased sleepiness and is the building block for Serotonin, which produces a calm, relaxed state. Foods high in Tryptophan include:

• Turkey, Rabbit, Lean Pork, Lamb, Beef, Chicken, Fish
• Baked potatoes with their skin
• Cheddar, Mozzarella, Romano, Cottage Cheese
• Shrimp, Scallops, Clams
• Pinto Beans, Kidney Beans, Lentils
• Milk

Tryptophan intake has been shown to increase blood melatonin levels fourfold (Sinha, 2015). Melatonin production normally occurs in response to the darkness of the evening hours and assist the body to gear down for sleep. Final meals of the day should include protein, carbohydrates, and calcium, which assist in the production of Serotonin.

Wait a minute! If some of these foods are on both lists, then how can I eat to promote wakefulness or sleep? Let’s go back to the Thanksgiving dinner. The turkey contains both Phenylalanine and Tryptophan, which is very good for your body. However, in order for the Tryptophan to cross the blood-brain barrier, it needs carbohydrates. Eating a high protein, low carbohydrate meal provides the essential amino acids your body needs to function and also limits its ability to use those amino acids which promote sleep. The turkey by itself will not make you sleepy, but when you add all the carbohydrates found in the rest of the dinner, the Tryptophan has a ticket into the brain where it can produce what we know as the turkey coma (Richard, Dawes, Mathias, Acheson, Hill-Kapturczak and Dougherty, 2009; Zamosky, 2009). Armed with this information, we can now see a diet for pilots that promotes wakefulness and sleep:

Pre-flight – Breakfast meals should contain proteins and minimal carbohydrates

In-flight – Lunch meals should contain proteins, fruits and vegetables and minimal carbohydrates

Post-flight – Dinner meals should contain proteins, carbohydrates, and calcium

And as always, limit your intake of sugar, saturated fats, cholesterol, and refined foods

As you can see here, your eating habits can either support or undermine your pilot work schedule requirements, making you sleepy or awake at the wrong times. However, when you line up your daily dose of food chemicals to support your duty day, everything works in unison to achieve the ultimate goal of keeping you at peak performance. If the moment requires you to be alert, you can set yourself up for success by minimizing carbohydrate intake. If the stage is set for sleep, you can finally indulge in those carbs and drift off to dreamland. Many times we grab a high-carb snack to keep us going when we should grab some beef jerky instead. Changing these small habits can make a big difference in how you feel as you will no longer be struggling against your body, but working together toward a sustainable and successful aviation career.

Get Started With Your Flight Training Today

You can get started today by filling out our online application. If you would like more information, you can call us at (844) 435-9338, or click here to start a live chat with us.

References:

Richard, D. M., Dawes, M. A., Mathias, C. W., Acheson, A. Hill-Kapturczak, N., Dougherty, D. M. (2009). L-Tryptophan: Basic Metabolic Functions, Behavioral Research, and Therapeutic Indications. Int J Tryptophan Res. 2009; 2: 45–60.

Sinha, A. (2015). Remedies and cures for the common diseases. Page Publishing, Inc.

Young, V. R. (1994). Adult amino acid requirements: the case for a major revision in current recommendations. J. Nutr 124 (8 Suppl): 1517S-1523S.

Zamosky, L. (2009). The truth about tryptophan.

Amber Berlin

The Clean Air Act, last amended in 1990, established a higher standard of environmental responsibility in the United States. In order to meet this standard, several initiatives were undertaken to reduce air emissions deemed harmful to human health. One such initiative was a close examination of the hazards presented by lead (Pb) fuel emissions. Pb fuel emissions are a by-product of the combustion of leaded gasoline in piston-engines, which are released into the air through the exhaust system. When airborne Pb is inhaled, it enters the bloodstream and raises the blood lead level (BLL) in the body. Because blood carries Pb through the entire body, it can result in widespread biological damage to cells and interruption of the cellular processes essential for cell survival.

Pb exposure is particularly dangerous to the brain because Pb has the ability to substitute for calcium ions and pass through the blood-brain-barrier (Sanders, Liu, Buchner & Tchounwou, 2009). Once in the brain, the toxic effects of Pb destroy healthy brain tissue and cause permanent damage in the central nervous system. According to Wu, Edwards, He, Zhen and Kleinman, (2010) substitution of Pb for calcium ions also affects the process of bone formation and remodeling, with Pb deposited in the bones in lieu of calcium and later released from bone tissue to recirculate in the body.

While it is known that large amounts of lead can be toxic, new research has shown that low-level lead exposure will also inhibit the brain’s ability to function. In a study on children, Miranda et al. (2007) show blood lead levels as low as 2 µg/dL (micrograms of lead in 100 ml of blood) have a significant impact on academic performance. This reduction in cognitive ability is identified as by The World Health Organization (2004) as “mild mental retardation resulting from loss of IQ points,” which has many negative effects on individuals and society as a whole (p.1495).

A loss of 2 IQ points has many social implications, such as moving an individual with a 71 IQ to below 70, an area considered mild mental retardation. While a drop in intelligence may affect the individual’s ability to perform academically, it also affects the way he or she is able to respond to the world. Individuals with limited intelligence tend to make less educated decisions than intelligent individuals, which may lead to fewer employment opportunities and various mistakes, even resulting in death. Furthermore, a self-awareness of having a below 70 IQ may create additional social problems because of a lack of confidence or self-esteem.

The monetary impact from a loss of 2 IQ points is substantial, with studies estimating the lifetime loss of income from the loss of IQ points ranges from $8,300 to $50,000/IQ point (Dockens, 2002; Pizzol, Thomsen, Frohn & Andersen, 2010). These losses extend beyond individual income and affect each member of society through our taxpayer dollars. An IQ below 70 qualifies children for special education classes and is also a qualifier for Social Security Disability benefits for intellectual disability (formerly known as mental retardation), which together cost nearly $8 billion a year.

While issues such as intellectual disability are apparent, the amount of toxic dust produced by Pb emissions often goes unnoticed. Pb dust is an invisible danger, settling on the surface of objects, vegetation, and into the top layers of soil. This dust is not easily removed from the environment, and according to Wu et al. (2010) Pb “does not appreciably dissolve, biodegrade, or decay and is not rapidly absorbed by plants” (p.309). The Pb in soil is a continuous hazard to small children because they absorb Pb more easily than adults and are more likely to ingest dirt. According to the World Health Organization (2010), an economic analysis revealed the cost of childhood lead poisoning to be $43 billion annually.

The Environmental Protection Agency (EPA) is the regulatory body charged with monitoring the national ambient air quality for Pb. After the identification of Pb fuel emissions as a health hazard, the EPA sought to reduce the amount of Pb in gasoline with the Clean Fuel Program in 1973. Highway use of leaded gasoline was finally prohibited in 1995.

In 2008, the EPA issued a final rule, lowering the National Ambient Air Quality Standard (NAAQS) from 1.5 µg/m3 (micrograms per cubic meter) to 0.15 µg/m3. The EPA acknowledged the acceptable risk of a loss of 2 IQ points, and used this as the measure to set the NAAQS for Pb (Chari, Burke, White & Fox, 2012). By 2012, the EPA had still not met the new standard and reported approximately 8.1 million people living in counties where Pb exceeds the NAAQS. The EPA also reported General Aviation (GA) is the leading contributor to Pb emissions through fossil fuel combustion in piston-engine aircraft, contributing an estimated 653 tons of airborne Pb annually (EPA, 2010).

Historically, General Aviation and GA aircraft have been exempt from a ban on leaded fuel because of its social and economic contribution. In 2005, General Aviation contributed $150.3 billion and over 1.2 million jobs to the U.S. economy (GAMA, 2006). Of the 3,300 airports open to the public and included in the FAA’s National Plan of Integrated Airport Systems (NPIAS), there are 2,952 landing facilities which depend on general aviation for community services such as aerial fire fighting support, aeromedical flights, agricultural support, aerial surveying, air cargo, disaster relief, remote population/island access, and U.S. Customs and border protection. GA links communities that would otherwise have no air support, providing vital services necessary for successful community development.

In 2010, piston-engine aircraft made up approximately 70% of the GA fleet, flying over 14.7 million hours. The majority of piston-engine aircraft use 100LL (Avgas), which may contain as much as 2.12 grams of Pb based fuel additive tetraethyllead (TEL) per gallon (EPA, 2008). The TEL additive boosts the octane rating and prevents early detonation of the fuel which may cause engine failure, but it is also the ignition of TEL that produces the Pb emission hazard.

While the entire population is affected by airborne Pb emissions, none is more affected than the population near airports. It is airports where Avgas is sold and used, where GA aircraft taxi and depart, and where the majority of Pb emissions are concentrated. A study on the impact of Avgas confirmed those living closest to the airport incur the greatest risks, including an estimated 16 million people living within 1km of an airport using Avgas, and 3 million children attend school within the same area (Miranda, Anthopolos & Hastings, 2011). The EPA also recognized their existing lead monitoring network is not sufficient to determine if all areas meet the new Pb NAAQS of 0.15 µg/m3.

The external costs of Pb emissions have been calculated at 41-83€/kg of emitted Pb (Pizzol et al., 2010), and for piston-engine aircraft, these external costs run approximately $37.5-$75.8 million per year.The health hazards and associated costs of Pb fuel emissions leave only one option for the GA fleet: stop using leaded fuel. In order to accomplish this task, GA has several options to consider, including renewable biofuel, fleet-wide modification, or to continue the search for a “drop-in” replacement that will meet or exceed the current engine specifications. Join us for the upcoming second part of this discussion as we discuss the future of GA fuel, including alternatives, and the FAA’s plan to phase out leaded avgas in Exploring Avgas Alternatives For General Aviation.

Get Started With Your Flight Training Today

You can get started today by filling out our online application. If you would like more information, you can call us at (844) 435-9338, or click here to start a live chat with us.

References:

Chari, R., Burke, T. A., White, R. H. & Fox, M. A. (2012). Integrating Susceptibility into Environmental Policy: An Analysis of the National Ambient Air Quality Standard for Lead. Int J Environ Res Public Health., 9(4), 1077–1096. doi: 10.3390/ijerph9041077

Dockins C. (2002). Valuation of childhood risk reduction: the importance of age, risk preferences and perspective. In: Jenkins R, Owens N, Simon N, Wiggins L, editors. Risk Anal: Int J, 22(2), 335–46.

Environmental Protection Agency. (2008). EPA-420-R-08-020.

Environmental Protection Agency. (2010). Development and Evaluation of an Air Quality Modeling Approach from Piston Engine Aircraft Operating on Leaded Aviation Gasoline. EPA-420-R-10-007. http://www.epa.gov/nonroad/aviation/420r10007.pdf

General Aviation Manufactures Association. (2006). GA Contribution. Retrieved from https://www.gama.aero/files/ga_contribution_to_us_economy_pdf_498cd04885.pdf

Miranda, M. L., Kim, D., Galeano, M. A., Paul, C. J., Hull, A. P. & Morgan, S. P. (2007). The relationship between early childhood blood lead levels and performance on end-of-grade tests. Environ Health Perspect, 115(8), 1242-7.

Miranda, M. L., Anthopolos, R., & Hastings, D. (2011). A Geospatial Analysis of the Effects of Aviation Gasoline on Childhood Blood Lead Levels. Environ Health Perspect, 119(10), 1513–1516. doi: 10.1289/ehp.1003231.

Pizzol, M., Thomsen, M., Frohn, L. M. & Andersen, M. S. (2010). External costs of atmospheric Pb emissions: Valuation of neurotoxic impacts due to inhalation. Environmental Health, 9(9). doi: 10.1186/1476-069x-9-9.

Sanders, T., Liu, Y., Buchner, V., & Tchounwou, P. B. (2009). Neurotoxic Effects and Biomarkers of Lead Exposure: A Review. Review of Environmental Health, 24(1), 15-45.

World Health Organization. (2004). Comparative Quantification of Health Risks. Global and Regional Burden of Disease Attributable to Selected Major Risk Factors. Chapter 19, p. 1495. Retrieved from http://www.who.int/publications/cra/chapters/volume2/1495-1542.pdf

World Health Organization. (2010). Childhood Lead Poisoning. Retrieved from http://www.who.int/ceh/publications/leadguidance.pdf

Wu, J., Edwards, R., He, X. (E.), Zhen, L., & Kleinman, M. (2010). Spatial analysis of bioavailable soil lead concentrations in Los Angeles, California. Environmental Research, 110, 309–317.

^{Featured Image: Erik Brouwer}

Wilson Gilliam Jr.

I stood in front of a Marine Corps recruiting office in 1988. I wanted to take the aviator’s aptitude test and join the Marines as a helicopter pilot. But, after a few minutes with the Sergeant, I realized that wouldn’t happen.

Between thirteen years old and eighteen, my visual acuity had decreased to 20/400. Even though it was still correctable to 20/20, the heavy eyelid morning routine of prying a way in for the contacts and the saline solution was getting rough. I wanted a permanent solution to the problem of seeing only the single, large E on the eye chart. I wanted to read the “made in USA” line without any help!

I had recently read a news article about the Russian military providing a corrective surgery called radial keratotomy (RK) for their soldiers that were nearsighted. Some further investigation revealed that a laser version of RK, called PRK (photorefractive keratectomy) was already being performed by a doctor in Windsor, Canada. Although the procedure was not yet legal within the United States, I could travel to Canada and get my eyesight corrected. That’s exactly what I did.

Armed with my new, crystal clear vision, I dived headlong into a career in aviation. I began teaching students in an Aeronca Champ and then in a Schweizer 300CBi helicopter, after I earned my helicopter flight instructor certificate. Our company went on to accomplish various things like flying an R-44 in the Florida keys for tours, repairing live power lines from a work platform, sling loading, side pulling in rope for new transmission conductors and many other things.

The improvement to my eyesight was a catalyst for the release of business fuel into my career in aviation. This was a motivation that lasted fifteen years, ending in 2014 when I sold my company.

During my final year at work, I noticed a high-pitched ringing noise in both ears as I would head back into the office after a flight. The episodes would increase in frequency each week and finally after a couple of months, the ringing in my ears was permanent. I went to see an audiologist and after an afternoon of tests, I learned that I had lost most of my hearing within a certain frequency range. The loss of hearing was creating a condition called tinnitus, which I live with today.

Shortly after the diagnosis of tinnitus, I noticed that a corner of the vision in my right eye had turned dark. A trip to the eye doctor revealed my worst fear – I had aggressive glaucoma.

When most people think about flying, they concentrate on protecting their eyes. But don’t forget about maintaining health in other areas. Protect your hearing. Even though I always wore headsets (or a flight helmet) it’s not enough. Put earplugs in as well. This should eliminate any long term hearing damage.

The most important lesson I learned from this experience should be that a routine, thorough medical exam (not just through your friendly FAA medical doctor) is super important in catching additional vision and hearing problems before they develop into serious issues. If I was able to travel back in time to the beginning of my career in aviation, I would go see eye and ear specialists every five years as a pilot. Ask your doctors to compare the condition of your eyes and ears to your last visit(s). There are stresses on those parts of the body that need to be closely tracked. If you can catch a starting and / or worsening condition quickly, it may not become debilitating.

Get Started With Your Flight Training Today

You can get started today by filling out our online application. If you would like more information, you can call us at (844) 435-9338, or click here to start a live chat with us.