Digestive Fuction and Testing

Digestive Fuction and Testing

Over 2,000 years ago Hippocrates, the father of medicine said: “All disease begins in the gut”. Healthy digestion and a healthy microbiome are fundamental to health. The digestive tract is a long tube that goes from the mouth to the anus. It is composed of several organs and accessory organs that work together to intake, break down and absorb food as well as excrete waste material. Each organ of the digestive tract can be affected by dysfunction from gastroesophageal reflux to H. Pylori infections, leaky gut, malabsorption syndrome, maldigestion, food allergies, celiac disease, irritable bowel syndrome, inflammatory bowel disease, etc. It is important to know that digestive issues are not confined to the affected organ, but that they have repercussions for the entire system. Moreover, digestive dysfunction causes maladies that are not exclusively relegated to the organs of digestion. Research shows that several conditions are caused by or correlated with unhealthy microbiome and digestive dysfunction: obesity, type-2 diabetes (Fan & Pedersen, 2021), connective tissue disease (CTD) (Bizzaro et al., 2003), systemic lupus erythematosus (SLE), Grave’s disease (Shor et al., 2012), just to name a few.

What Laboratory Tests Are Available Today?

There are several laboratory tests available to test gastrointestinal function. Stomach acid can be measured with a Heidelberg capsule (Lord & Bralley, 2012). Pepsin can be tested via a saliva test (Strugala et al., 2015). Fecal and plasma tests can be used to measure pancreatic output of protease and lipase. A fecal fat test can reveal impaired liver or gallbladder function. Stool cultures, DNA stool test, comprehensive stool digestive analysis (CSDA), fecal butyrate testing are tools used to assess colon function (Lord & Bralley, 2012). Colonoscopy, barium enema, magnetic resonance imaging (MRI), computed cosmography scan (CT scan), defecography, ultrasounds and other imaging tests are also available to assess colon health (Digestive Diagnostic Procedures). A hydrogen-methane breath test is used to diagnose small intestinal bacterial overgrowth (SIBO). 

Several tests are available to test for food allergies and intolerances: increased levels of IgA can be measured through feces, urine and serum analysis and can reveal the presence of gut inflammation, celiac disease, mucosal infection, food allergies, and other inflammatory conditions (Breedveld & van Egmond, 2019). Serum IgE and IgG levels can be checked to test for food allergies, infections and inflammatory diseases (Mayo Clinic Labs). According to the Genova Diagnostics website, high levels of IgG antibodies can also indicate the presence of leaky gut syndrome. 

What Is The Helicobacter Test?

The test I chose for this essay is the Helicobacter Pylori Stool Antigen EIA. The American Gastroenterological Association (AGA) (Talley et al., 2005) and the American College of Gastroenterologists (ACG) (Chey et al., 2007) consider the H. Pylori stool antigen to be superior to the serum testing. 

H. Pylori is a bacterium that inhabits the stomach, usually without causing any disease. According to Iisashi et al. (2015) H. Pylori can suppress inflammatory bowel disease (IBD), and it is linked to a reduced incidence of asthma. A study from Talebi Bezmin Abadi (2014) even suggested that an eradication of H. Pylori contributes to an increase of GERD. It is still unknown why, in certain people, H. Pylori colonies wreaks havoc in the stomach, causing stomach ulcers, gastric inflammation, stomach cancer and gastric mucosa-associated lymphoid-tissue lymphoma (Yang it al., 2014). Symptoms associated with H. Pylori infections are burping, bloating, nausea, gastritis presenting with pain and a burning sensation, loss of appetite and weight loss (Mayo clinic, 2017).  A patient that presents with these symptoms should be tested for H. Pylori infection. The stool antigen EIA test looks for the present of antigens that reveal the presence of H. Pylori. Certain medications like antibiotics and acid blockers can interfere with the test results; therefore, patients are asked to discontinue the use to these medications for one to two weeks prior to testing. 


Bizzaro, N., Villalta, D., Tonutti, E., Tampoia, M., Bassetti, D., & Tozzoli, R. (2003). Association of celiac disease with connective tissue diseases and autoimmune diseases of the digestive tract. Autoimmunity reviews, 2(6), 358–363. https://doi.org/10.1016/s1568-9972(03)00055-7

Bravo, D., Hoare, A., Soto, C., Valenzuela, M. A., & Quest, A. F. (2018). Helicobacter pylori in human health and disease: Mechanisms for local gastric and systemic effects. World journal of gastroenterology, 24(28), 3071–3089. https://doi.org/10.3748/wjg.v24.i28.3071

Breedveld, A., & van Egmond, M. (2019). IgA and FcαRI: Pathological Roles and Therapeutic Opportunities. Frontiers in Immunology, 10. https://doi.org/10.3389/fimmu.2019.00553

Chey WD, Wong BC; Practice Parameters Committee of the American College of Gastroenterology. American College of Gastroenterology guideline on the management of Helicobacter pylori infection. Am J Gastroenterol. 2007;102:1808-1825.

Digestive Diagnostic Procedures. (n.d.). Www.hopkinsmedicine.org. https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/digestive-diagnostic-procedures

Fan, Y., & Pedersen, O. (2021). Gut microbiota in human metabolic health and disease. Nature reviews. Microbiology, 19(1), 55–71. https://doi.org/10.1038/s41579-020-0433-9

Gastrointestinal Test | helicobacter pylori Stool Antigen EIA. (n.d.). Www.gdx.net. Retrieved July 16, 2021, from https://www.gdx.net/product/helicobacter-pylori-stool-antigen-eia-test

www.gdx.net. (2010). Food Sensitivity Test | IgG Food Antibody Assesment. Gdx.net. https://www.gdx.net/product/igg-food-antibodies-food-sensitivity-test-blood

IGE – Clinical: Immunoglobulin E (IgE), Serum. (n.d.). Www.mayocliniclabs.com. https://www.mayocliniclabs.com/test-catalog/Clinical+and+Interpretive/8159

Iizasa, H., Ishihara, S., Richardo, T., Kanehiro, Y., & Yoshiyama, H. (2015). Dysbiotic infection in the stomach. World journal of gastroenterology, 21(40), 11450–11457. https://doi.org/10.3748/wjg.v21.i40.11450

Lord, R. and Bralley, J., n.d. Laboratory evaluations for integrative and functional medicine. 2nd ed. (2012), Metametrix institute.

Lu, P. J., Hsu, P. I., Chen, C. H., Hsiao, M., Chang, W. C., Tseng, H. H., Lin, K. H., Chuah, S. K., & Chen, H. C. (2010). Gastric juice acidity in upper gastrointestinal diseases. World journal of gastroenterology, 16(43), 5496–5501. https://doi.org/10.3748/wjg.v16.i43.5496

Mayo Clinic. (2017). Helicobacter pylori (H. pylori) infection – Symptoms and causes. Mayo Clinic; https://www.mayoclinic.org/diseases-conditions/h-pylori/symptoms-causes/syc-20356171

Shor, D. B., Orbach, H., Boaz, M., Altman, A., Anaya, J. M., Bizzaro, N., Tincani, A., Cervera, R., Espinosa, G., Stojanovich, L., Rozman, B., Bombardieri, S., Vita, S. D., Damoiseaux, J., Villalta, D., Tonutti, E., Tozzoli, R., Barzilai, O., Ram, M., Blank, M., … Shoenfeld, Y. (2012). Gastrointestinal-associated autoantibodies in different autoimmune diseases. American journal of clinical and experimental immunology, 1(1), 49–55. 

Strugala, V., Woodcock, A. D., Dettmar, P. W., Faruqi, S., & Morice, A. H. (2015). Detection of pepsin in sputum: a rapid and objective measure of airways reflux. European Respiratory Journal, 47(1), 339–341. https://doi.org/10.1183/13993003.00827-2015

Talebi Bezmin Abadi A. (2014). Helicobacter pylori: A Beneficial Gastric Pathogen?. Frontiers in medicine, 1, 26. https://doi.org/10.3389/fmed.2014.00026

Talley NJ; American Gastroenterological Association. American Gastroenterological Association medical position statement: evaluation of dyspepsia. Gastroenterology. 2005;129:1753-1755.

Yang, J. C., Lu, C. W., & Lin, C. J. (2014). Treatment of Helicobacter pylori infection: current status and future concepts. World journal of gastroenterology, 20(18), 5283–5293. https://doi.org/10.3748/wjg.v20.i18.5283

Elimantion Diets: What You Need To Know

Elimantion Diets: What You Need To Know

According to Dr. O’Neil-Smith, more than 20% of the population suffers from food allergies and intolerances. Elimination diets and IgG food antibody testing can be successfully used in clinical practice to address symptoms like bloating, constipation and diarrhea, fatigue, anxiety, asthma, joint pain, sleep disturbance, and headaches. As practitioners, we must relate this information to clients and patients in an easy-to-understand manner. When I introduce an elimination diet to my clients, I explain that eliminations diets are a great tool to identify food allergies and sensitivities. I would like the client to keep a food/symptom log for five days to see if there are patterns that can point to specific foods causing symptoms. The only downside is that not all reactions are immediate. Some foods can cause delayed reactions, meaning that an offending food can cause a reaction from several hours to several days after it has been ingested. This can make keeping a food/symptom log frustrating and confusing.

What Is The Difference Between An Allergy and A Sensitivity

I think that when we discuss elimination diets, it is important to understand the difference between a true allergy and a sensitivity. Food allergies can be life-threatening due to anaphylaxis. Food sensitivities can be caused by physiological and psychological issues. For example, leaky gut causes maldigested food particles to diffuse in the bloodstream, which causesimmune cells to mount an attack. Overgrowth of bacteria in the small intestine (SIBO) can cause severe reactions to fermentable foods, and it needs to be addressed with a very specific elimination diet called low-FODMAP. Enzyme deficiency and irritable bowel can also cause food intolerances. Stress and psychological factors can also be responsible for food reactions. To this day, there are foods I was forced to eat as a child that will literally make me sick, even though I do not have a true immune reaction to them. We can also be sensitive to “added” substances like food coloring, preservatives, and sulphites (Li, J. 2019).

Elimination Diets Need To Be Tailored To Individual Needs

For these reasons, the elimination diet needs to be tailored to the individual and their specific symptom burden. We must understand that an elimination diet does not merely remove foods, but it also prescribes that the client eats specific foods. For example, if leaky gut is the cause of food intolerances, we need to make sure that their diet includes plenty of gut healing foods. The same applies when we are dealing with food intolerances caused by imbalanced gut flora or irritable bowel. We can’t just refrain from eating offending foods; we must ensure that our diet is nutrient dense and health-promoting (Rinninella et al., 2019).

The good news is that food intolerances usually resolve themselves in a matter of 3 to 6 months, when the client avoids offending foods completely, and we address the root causes of the intolerances. While implementing an elimination diet, we monitor progress closely. This allows us to fine-tune the diet, and it also helps us to decide when the client is ready to reintroduce and to test the foods that were triggering a reaction. The reintroduction phase of the diet is as important as the elimination phase. We must not rush through the process. When symptoms have resolved, we will decide together which foods to reintroduce in the diet and in 

which order. It is important that the client tests one food at a time every 4 to 5 days. This allows us to see if there are any delayed reactions to the food that we reintroduce. Keeping a detailed food/symptom log is going to be very useful during the reintroduction phase. 


Li, J. (2019). Food allergy vs. food intolerance: What’s the difference? Mayo Clinic; https://www.mayoclinic.org/diseases-conditions/food-allergy/expert-answers/food-allergy/faq-20058538

O’Neil-Smith, K. (n.d.). Using the elimination diet in clinical practice: Explanations and case studies [Video]. Genova Diagnostics. https://www.gdx.net/clinicians/medical-education/previous-webinars/using-the-elimination-diet-in-clinical-practice

Rinninella, E., Cintoni, M., Raoul, P., Lopetuso, L. R., Scaldaferri, F., Pulcini, G., Miggiano, G., Gasbarrini, A., & Mele, M. C. (2019). Food Components and Dietary Habits: Keys for a Healthy Gut Microbiota Composition. Nutrients, 11(10), 2393. https://doi.org/10.3390/nu11102393

Cholesterol Intake Effects Insulin Production

Cholesterol Intake Effects Insulin Production

What are the roles of lipoproteins and cholesterol in the body? Consider the interplay of insulin and cholesterol. How does a client’s insulin level impact his/her level of cholesterol? What is the current standard of care for someone who presents with elevated cholesterol? In what ways does this current standard of care affect insulin levels? Outline a nutritional protocol to help your client address his/her concerns of high cholesterol. Include labs might you request from your client’s primary care provider to assist you in designing this protocol. (600 words)

Lipids are hydrophobic: they are non-polar and insoluble in water.  This means that they cannot dissolve in blood and rely on special particles for transport.  These particles are called lipoproteins.  Lipoproteins are a group of proteins synthesized in the small intestine and liver that transport hydrophobic lipids throughout the body.  Lipoproteins are made up of lipids and proteins.  The hydrophobic lipid portion of lipoproteins is placed in the core, while the hydrophilic protein portion is placed in the periphery of the particle.  This particular structure is what allows lipoproteins to travel in the blood and transport lipids through the body. 

Find Out What The Different Types of Lipoproteins and Their Names

There are different types of lipoproteins, and they are named according to the density of their content: chylomicron, chylomicron remnant, very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), low density lipoprotein (LDL), and high density lipoprotein (HDL).  Chylomicrons are the least dense while HDL are the densest. 

The lipids present in lipoproteins are triglycerides, phospholipids, free cholesterol, and cholesterol ester.   Cholesterol is a high-molecular-weight alcohol, and it comes from two sources: exogenous (dietary cholesterol contained only in food from animals) and endogenous (manufactured by the liver).  Cholesterol has several vital functions within the body.  It gives our cells stability and stiffness.  It is a precursor for the synthesis of steroid hormones, vitamin D, and bile, and it acts as an antioxidant.  Cholesterol is needed for serotonin function, and low levels of cholesterol have been linked to aggressive behavior, violence, depression, and suicidal tendencies.  Breast milk is rich in cholesterol, and infants and children need cholesterol-rich foods for proper development of the brain and nervous system.  Cholesterol is also considered the “duct tape” of the body, used to repair damaged tissues.  

Cholesterol and Heat Exposure

Cholesterol can become damaged upon exposure to heat and oxygen.  Oxidized cholesterol is found in foods like fast foods, fried foods, margarines, baked goods, and foods that are deep fried in rancid vegetable oils.  

Several studies reveal that prolonged exposure to insulin is linked to higher levels of lipid peroxidation markers in LDL.  For this reason, we need to be aware that clients suffering from hyperinsulinemia will present higher levels of LDL compared to clients with normal blood sugar metabolism.  The cholesterol guidelines from the American College of Cardiology and American Heart Association are as follows: patients with arterial plaques and otherwise healthy patients with LDL-C levels greater than or equal to 190 mg/dl are advised to drastically reduced intake of dietary cholesterol and are prescribed high-intensity statin therapy (or maximum tolerated statin therapy).  Diabetic patients between the ages of 40 and 75 with LDL-C levels greater than or equal to 70 mg/ dl are prescribed moderate-intensity statin.  It is disheartening to see such guidelines in place and to read that many expert physicians consider them not aggressive enough.  Statins are dangerous medications linked to a host of side effects including memory loss and confusion, liver damage, muscle pain and damage.  Statins also activate an immune response that prevents insulin from working correctly, causing an increase in blood sugar and, therefore, a higher incidence of diabetes.  While as a nutritionist I cannot recommend against doctor’s orders, it is my duty to provide my clients with the latest research and information necessary to make informed decisions. 

What Is High Cholesterol and How To Bring The Levels Down

When working with clients who are concerned about high cholesterol levels, some of the tests that I find helpful are the advanced lipid tests LDL particle number (LDL-P) and apolipoprotein B (apoB) as well as serum insulin test and c-reactive protein.  These tests all measure biomarkers that can accurately predict risk of cardiovascular disease. 

The nutritional protocol for such clients focuses on an anti-inflammatory diet that supplies high quality proteins, fats, and carbohydrates from low-glycemic vegetables and fruits.  The diet removes added sugars, processed foods, fried foods, and vegetable oils.  I also help them with stress management techniques and sleep hygiene.  Supplements are an important part of nutritional therapy and, while there is no typical protocol, nutrients that are helpful in cases presenting high cholesterol are: chromium: 200-400 mcg with each meal; vitamin E: 200-600 IU d-alpha and d-gamma tocopherol; l-arginine: 700 mg two to three times a day with meals; magnesium orotate: starting with 400 mg and dosed to bowel tolerance; and curcumin: 15-60 mg three times a day.  A formulation that I have used with success is Lipid-Sirt from Biotics Research. 


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Food Consumption And Body Metabolism

Food Consumption And Body Metabolism

Our total daily energy expenditure (TDEE) is dictated by three factors: resting metabolic rate (RMR), which is the number of calories our body needs to perform metabolic functions when it is at rest; the number of calories burnt through physical activity, non-exercise activity thermogenesis (NEAT), and exercise; and the number of calories needed to digest and absorb food.  This is called diet-induced thermogenesis (DIT) or thermal effect of feeding (TEF).

Total daily energy expenditure varies from individual to individual and across age, sex, total body weight, physical activity, percentage of fat free mass (FFM), also called lean body mass, versus fat mass (FM), as well as hormones; all play a role in TDEE.  In general, RMR accounts for 60% of TDEE, physical activity account for 25-35% of TDEE, and DIT accounts for 5-15% of total energy expenditure. 

How Is Food Converted Into Usable Energy?

The foods and beverages that we consume are combined with oxygen and converted into energy in the form of ATP.  They also provide the building blocks used to make hormones and enzymes to grow and repair tissue as well as many other processes.  When we eat, digest and assimilate food we burn calories.  Diet-induced thermogenesis begins immediately after we eat and can last several hours, depending on the macronutrient composition of the meal.  The word thermogenesis comes from the Greek θερμός (thermos) and γένεση (genesis), and it means the creation of heat.  Not only does DIT create heat during food digestion and absorption, but it also (by a mechanism still not completely understood) activates the sympathetic nervous system which causes the body to produce heat in brown adipose tissue (BAT).  BAT is only stimulated by cold temperatures (shivering) and food consumption.  

What Exactly Is A Calorie?

A calorie is a unit of energy.  It would be simple to think that a calorie is a calorie and that, therefore, 100 calories of steak are the same as 100 calories of brownies, or butter, or broccoli.  But different macronutrients require different amounts of ATP to be metabolized and stored. This is why different macronutrients have different thermogenic effects, and DIT can vary greatly depending on the macronutrient composition of our diet.  

    Protein and alcohol have the highest thermic effects.  The DIT for protein is calculated to be between 20 to 30%; the DIT of alcohol is between 10 and 30%.  The thermic effect of carbohydrates is between 5 and 10%, and fat has the lowest reported DIT: 0 to 3%.  This means that given the same number of calories, meals rich in protein, fat, carbohydrate, or alcohol have different effect on energy expenditure.  

Studies show that postprandial thermogenesis in healthy subjects is increased 100% on a high-protein/low-fat diet versus a high-carbohydrate/low-fat carbohydrate diet.  In addition, compared to fats and carbohydrates, protein consumption also provides increased satiety.  Satiety scores were higher during high protein/high carbohydrate meals versus high fat meals. For these reasons, high protein diets are favored for weight loss as well as for weight maintenance. 

How Does Food Effect Metabolism?

When researching the effects of food on metabolism, the next logical question to address is the following: would eating many smaller meals burn more calories than eating one to two larger meals in a 24-hour period?  I found contradicting studies when reviewing the literature.  Some studies showed that nibbling throughout the day caused a greater caloric expenditure, while other studies showed that consuming larger meals was linked to greater caloric expenditure.  It seems that when it comes to meal frequency and metabolism the jury is still out.

There are other nutrients that stimulate metabolism and cause thermogenesis without contributing any calories.  These nutrients are caffeine, capsaicin, and cold water.  Caffeine is an alkaloid found in coffee beans, tea leaves, and cocoa beans.  It is a stimulant and studies show that a cup of coffee can boost metabolism by 3-11%.  A study also showed that caffeine may affect lean people more than overweight people as fat burning in lean women increased by 29% with caffeine consumption but obese women registered an increase of only 10%.  Capsaicin is a compound found in chili peppers that stimulates metabolism and helps reduce energy intake.  Finally, consuming water increases metabolism by 10-30% for about an hour.  Cold water may promote an even greater caloric expenditure, as the body uses extra energy to raise the water temperature to body temperature. 


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Nutrition For Female Marathon Runners

Nutrition For Female Marathon Runners

There is no one-size-fits-all in nutrition, and nutrient requirements vary based on age, sex, physical activity, and even illness.  As nutritionists, we need to ensure that our plans meet our client’s unique individuality, as well as their goals. 

Case Example Of a Young Female Marathon Runner

In this case, my 25-year-old marathon runner’s goal is to improve performance and feel her best during each race.  She needs recommendations for what to consumer before, during, and after her races to ensure performance as well as recovery.  A female athlete’s nutritional needs are quite different from those of male athletes: factors that come into play include bone density, as well as differences in caloric consumption and expenditure.  While both male and female athlete require more dietary protein than the average couch potato, the maximal increase is about 100% for male athletes and 50-60% for female athletes.  Proteins are essential for the marathon runner. 

Foods For Faster Recovery

They promote faster recovery after training and race, facilitating muscle growth and repair.  Protein also are needed in the synthesis of new structures, red blood cell development, and antibody production. When glycogen stores are low, the protein stores provide about 15% of the needed energy during muscle activity.  Those who lack protein are at an increased risk of injury, fatigue, and decreased muscle mass, all factors that hinder performance.  My client’s diet plan will include: organic eggs, wild-caught fish, pastured chicken and grass-fed meat, peanut butter and other nuts, if tolerated. 

Carbohydrates and Fats For High Performance Runners

Fats should also be a vital inclusion in marathon runners’ nutritional plan.  Fats are more calorie-dense, providing 9 calories per gram compared to the 4 calories per gram provided by protein and carbohydrates.  Additionally, fats are essential for the transportation of fat-soluble vitamins, for hormone production, brain function, and satiety.  A low-fat diet in athletes can limit athletic performance causing earlier onset fatigue during a race. Sources of fats include coconut oil, extra virgin olive oil and olives, butter and ghee, dairy, avocado, and if tolerated dairy.  

Carbohydrates are important for providing energy during the races.  The runner should be able to consume and maintain optimum carbohydrate intake.  This will help prevent hypoglycemia during the races, maintain the intensity of training, strengthen the immune system, and facilitate post-recovery.  If this client does not consume enough carbohydrates, she will not be able to endure and perform effectively due to increased glucose depletion.  Before a marathon, the total caloric intake should also be increased, including the carbohydrate calories, to achieve an effective carbohydrate-caloric loading effect. 

What Is The General Nutritional Advice Given To Marathon Runners?

The general advice given to marathon runners is to consume fruit juice, honey, molasses, whole-grains, cereals, rice and pasta, starchy carbohydrates and legumes, as well as fruit and high-carbohydrate dairy products such as yogurt.  About 60 to 70% of the calories should be from carbs. Before the race, only quick sources of energy should be consumed because they are absorbed faster.  During the race, she should increase the rate of carbohydrate intake by one gram per minute by consuming carbohydrate-containing drinks.  These drinks should be consumed at regular intervals during the race, and oftentimes an alarm can help keep track.  Additionally, consumption of carbohydrates with high glycemic index such as honey can help during the marathons.  After the races, the goal is to replace the depleted energy stores and fluids.  Attention should also be directed to muscle repair and recovery; hence, micronutrients and proteins will be essential.  Fast recovery is important so that the body can be ready to get back to training.  Carbohydrates will help restore glycogen stores; protein will help with muscle repair and recovery, and electrolytes will help in re-hydrating.  

Every Athlete Has Unique Nutritional Requirements

While the general advice has been used in sports nutrition for decades, I like to use a more individual approach with my athletes.  In my work, I have found that using a continuous glucose monitor is paramount to study each individual athlete’s response to carbohydrates and glucose.  Too much or too little glucose can be detrimental to athletic performance leading up to and during an event. Glucose levels are complex and many factors can influence them.  Plus, every athlete has unique fueling requirements. A continuous glucose monitor is my preferred tool when working with athletes.  For this reason, I will recommend that this client use this tool to learn how her body responds to different carbohydrates.  This will help us find the perfect nutrition for performance.  Athletes usually begin glucose loading 3 days before a race.  Knowing how her body responds to different foods will allow this client to eat meals that provide a stable and sustainable glucose rise and that will keep her in optimal fuel range. 

Hydration is extremely important. Before and during a marathon, my client will make sure to keep well hydrated.  I recommend electrolyte supplements, mineral-rich water, and coconut water.  

Other factors to consider are vitamins and minerals.  Calcium, for example, is an essential mineral needed for bone growth, density, and prevention of bone loss and fractures.  Consumption of calcium-rich foods help maintain strong bones that can endure the intensity of the races.  Therefore, this client should consume foods rich in calcium like dairy products, green leafy vegetables, spinach, and broccoli. 

B Vitamins And The Health Of Female Athletes

Vitamins are essential nutritional components for the marathon runner.  The most important vitamins are vitamin D and B complex vitamins.  The body needs vitamin D to metabolize calcium.  Vitamin D is necessary for a healthy immune system and hormone production. Therefore, I will advise my client to include fatty fish in her diet and supplement with vitamin D3 if needed.  Vitamin B6, B12, and Folate are also important.  For example, vitamin B12 and folate are essential for red blood cell development, protein synthesis, and tissue repair.  These are important in improving the oxygen-carrying capacity and building endurance during long races. 

My client will begin adopting her new dietary plan during training so that she can get used to the changes and, if needed, we can modify the plan according to her needs well before the race.  


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Smith-Ryan, A. E., Hirsch, K. R., Saylor, H. E., Gould, L. M., & Blue, M. (2020). Nutritional Considerations and Strategies to Facilitate Injury Recovery and Rehabilitation. Journal of athletic training, 55(9), 918–930. 

Thomas, D. T., Erdman, K. A., & Burke, L. M. (2016). American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance. Medicine and science in sports and exercise, 48(3), 543–568. 

Malnutrition Conditions: Marasmus & Kwashiorkor

Malnutrition Conditions: Marasmus & Kwashiorkor

The human body needs a balance of protein, fat, and carbohydrate to maintain health and vitality.  When the body does not get enough food, undernutrition occurs. When the body does not get enough nutrients, malnutrition occurs. Both undernutrition and overnutrition can cause malnutrition . While deficiency in each macronutrient is problematic, protein deficiency is extremely dangerous and can cause protein-energy malnutrition (PEM) (Maleta K., 2006).

There are two types of protein-energy malnutrition: one is associated with protein deficiency in the absence of sufficient caloric intake, the other presents with both protein and energy deficiency.  The main disorders associated with protein-energy malnutrition are kwashiorkor and marasmus syndrome. Kwashiorkor is caused by protein deficiency while marasmus is caused by energy deficiency. A third condition called marasmic kwashiorkor presents symptoms of both kwashiorkor and marasmus. 

These diseases are prevalent in the developing world, where they affect mostly infants and children. They are also present in economically developed countries, where they affect food-insecure populations and the elderly, especially the hospitalized elderly. PEM can have secondary causes, namely chronic diseases such as chronic kidney disease, cancer cachexia, AIDS, and anorexia (Grover & Ee, 2009) (Merck Manuals, 2021). 

The Dangers of Kwashiorkor & Marasmus

The severity of kwashiorkor and marasmus varies from subclinical deficiency to wasting syndrome to starvation. Adequate nutrition is necessary to combat both diseases, but, unfortunately, it is not enough to undo the metabolic damage done, especially with regards to stunted growth. 

Kwashiorkor is caused by insufficient protein intake in the presence of sufficient calories. Sadly, this severe form of malnutrition is very common in developing countries, where infants and children do not get enough dietary protein. Certain African regions report kwashiorkor rates as high as 15% (WHOs Africa Nutrition Report Highlights an Increase in Malnutrition in Africa., 2021). Kwashiorkor has acute onset, and its main characteristic is edema. Edema usually starts in the legs, but it can spread to the entire body, including the abdomen and the face. Kwashiorkor is also usually accompanied by fatty liver, muscle wasting, loss of hair and decreased hair pigmentation, stunted growth, skin lesions, anemia, diarrhea, apathy and listlessness (NHS website, 2019). 

Malnutrition & Portein Deficiency

Marasmus protein deficiency occurs when a person’s diet is deficient in both protein as well as calories.  Marasmus starts generally immediately after birth.  Infants affected by marasmus are slow to develop and present stunted growth, extremely low body weight, muscle wasting, depletion of adipose tissue, hypotension, and they suffer from repeated infections.

PEM conditions present also with deficiency of micronutrients, especially iron, iodine, zinc and vitamin A.  According to Merk Manual the mortality rate in children affected by PEM varies from 5% to 40%. Severe PEM causes electrolyte imbalance, sepsis, heart failure, and hypothermia, which can lead to shock and death. Patients affected by kwashiorkor recover more rapidly than patients affected by marasmus. 

As mentioned above, PEM therapy includes adequate nutrition; supportive care is considered on a case-to-case basis. Appetite stimulants are generally part of PEM therapy for patients affected by anorexia. Patients with cachexia can often be prescribed anabolic steroids or growth hormone. Refeeding syndrome is a complication of PEM therapy, which can be accompanied by hyperglycemia, diarrhea, fluid imbalance, and arrhythmias (Merck Manuals, 2021). 


December 8th F, 2019. Malnutrition in America [Internet]. Focus for Health. 2019. Available from: https://www.focusforhealth.org/malnutrition/

Grover, Z., & Ee, L. C. (2009). Protein energy malnutrition. Pediatric clinics of North America, 56(5), 1055–1068. https://doi.org/10.1016/j.pcl.2009.07.001

Maleta K. (2006). Undernutrition. Malawi medical journal : the journal of Medical Association of Malawi, 18(4), 189–205. 

Merck Manuals. (2021). Protein-Energy Undernutrition (PEU). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/nutritional-disorders/undernutrition/protein-energy-undernutrition-peu

NHS website. (2019, September 10). Kwashiorkor. Nhs.Uk. https://www.nhs.uk/conditions/kwashiorkor/

WHOs Africa Nutrition Report highlights an increase in malnutrition in Africa. (2021, September 1). WHO | Regional Office for Africa. https://www.afro.who.int/news/whos-africa-nutrition-report-highlights-increase-malnutrition-africa

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