Learning Objectives
At the end of the chapter, the learner will:
- relate concepts of nutrition and metabolism with GI assessment and elimination.
- identify patients at risk for developing malnutrition.
- use nutritional assessment in the provision of health care.
- document findings using correct medical terminology.
I. Overview of Nutritional Assessment
Proper nutrition is important to maintain health and prevent illness. It is essential for the health care provider to routinely evaluate patient’s nutritional status and to identify any nutritional problems or potential problems, so that appropriate referrals and interventions can be provided.
Many physical conditions can cause disturbance of nutritional absorptions. For example, patients with gastrointestinal problems such as inflammatory bowel disease or liver cirrhosis may have malnutrition issues; patients with lung problems may not have enough oral intake due to difficulty breathing; diabetes patients will have inadequate glucose homeostasis; patients who have psychiatric disorders or depression may have functional impairments that cause poor nutritional intake; cancer patients may result cancer cachexia and malnutrition; patients who are in pain may decrease oral intake.
Effects and adverse effects of many medications can interfere nutritional absorptions. For example, diuretics may cause dehydration and electrolyte abnormalities; narcotics/opioids may have adverse effects of nausea and vomiting; anticholinergic drugs may cause dry mouth and affect food intake.
Malnutrition is defined as “deficiencies, excesses, or imbalances in a person’s intake of energy and/or nutrients” (WHO, 2021). According to the World Health Organization (WHO), the following conditions can all be referred as malnutrition. These forms of malnutrition include,
- undernutrition: wasting (low weight-for-height), stunting (low height-for-age), and underweight (low weight-for-age);
- micronutrient-related malnutrition: vitamins or minerals deficiencies or excess;
- overweight, obesity, and diet-related noncommunicable diseases (NCDs): body mass index (BMI) over 25 kg/m2 is overweight; BMI above 30 kg/m2 is obesity. Diet-related NCDs include cardiovascular disease, diabetes, and certain cancers (such as liver cancer or oral cancer).
Body Mass Index (BMI) is using the person’s weight and height to estimate body fat. Through many research findings, BMI is highly correlated with many metabolic and cardiovascular diseases (CDC, nd.).
BMI Calculator
Click the link of BMI Calculator and follow the instructions to calculate your BMI (NHLBI, nd.).
| BMI (kg/m2) | Status |
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Normal weight |
| 25 – 29.9 | Overweight |
| Above 30 | Obese |
II. Anatomy and Physiology
Digestion begins in the mouth where chewing and mixing with saliva is the initial step in breaking down food. In stomach, foods mix with gastric juices and produce a mixture, chyme. Chyme passes to small intestine where most of the digestion takes place. In the small intestine, foods are dissolved, and nutrients are absorbed into the body. Unabsorbed wastes are passed down to the colon.
Nutrients are divided into macronutrients and micronutrients.
Macronutrients refer to carbohydrates, fats, and proteins that a person needs to consume daily to produce energy in order to function properly.
Watch the following short video clip to review digestion in small intestines.
Micronutrients refer to dietary minerals and vitamins that support metabolism of the body.
The following short video clip provides knowledge on nutrients that are essential for life: minerals and vitamins.
Knowledge Check
III. Medical Terminology
| Anthropometry | measurement of the body including height, weight, skinfold thickness |
| Body mass index (BMI) | a measure of body fat based on height and weight; a person’s weight in kilograms divided by the square of height in meters |
| Malnutrition | deficiencies, excesses, or imbalances in a person’s intake of energy and/or nutrients |
| Obesity | is defined as abnormal or excessive fat accumulation that poses a risk to health; BMI >30 |
| Recommended dietary allowance (RDA) | the levels of intake of essential nutrients sufficient to meet the nutrient requirements of practically all healthy people |
| Failure to thrive | in the elderly, weight loss of more than 5%, decreased appetite, poor nutrition, and physical inactivity, often associated with dehydration, depression, and immune dysfunction; a state of decline |
IV. Nutritional Assessment
Nutritional assessment is an ongoing component for daily assessment especial for patients with nutritional concerns and patients who are at risk for nutritional deficits.
| Screening for Nutritional Status | Additional Information |
1. Obtain health history
| Dietary and nutritional differences can be found among racial and socioeconomic groups. Dietary selections can be affected by religious, spiritual, or philosophical beliefs. |
2. Obtain chief complaints
| Chief complaints should be considered because it may indicate the patient to be at risk for nutritional deficits. Problems with intake such as indigestion, heartburn, bloating, difficulty chewing or swallowing will affect nutritional status. If the patient has a specific concerns about hair, skin, or nails, a focused assessment regarding to the specific sign/symptom should be performed. |
3. Check
| Note the size of the patient and calculate BMI to determine normal, overweight, or obesity. Waist circumference can also be measured for adult patients to determine if the patient is at risk for cardiovascular disease. Normal waist for men should be less than 40 inches; for women, less than 35 inches (Hinkle & Cheever, 2018).  |
4. General inspection and examination
| During the meal time, observe the patient’s dietary intake and compare with recommended food groups for specific age groups and activity levels. Expected findings are alert & oriented, normal proportion of body structure, normal skin tone and skin color appropriate to ethnicity, no signs of malnutrition. Many diseases are directly or indirectly caused by a lack of essential nutrients in the diet. Changes in the skin and mucosal membranes can offer valuable clues to the presence of nutritional deficiencies. For example, gingivitis and bleeding gums may cause by vitamin C deficiency. For integumentary system, in malnutrition patients, hair is likely to be brittle and dry, and or hair loss; skin is likely to be pale, dry, and rough; wounds will tend to take longer time to heal. Physical difficulties, such as tremors, will affect dietary intake. Nurses should assess if equipment is needed to help with eating and drinking. |
| 5. Review related laboratory results | Some laboratory values may reflect the patient’s nutritional status such as albumin, prealbumin, transferrin, electrolytes, and etc. |
| 6. Report and document assessment findings and related health problems according to agency policy. | Accurate and timely documentation and reporting promote patient safety. Recommend additional nutritional evaluation referrals such as dietitian to determine the need for nutritional supplements. |
General Assessment for Nutritional Status (Hinkle & Cheever, 2018)
| Body Parts | Normal Findings | Signs of Poor Nutrition (will require further assessment) |
| Appearance | alert and oriented | lack of energy |
| Weight | normal for height and age | overweight or underweight |
| Face | consistent skin color | face swollen, skin flaky |
| Lips | pink color, smooth | swollen and puffy, lesion at the corner |
| Tongue | papillae present | smooth and shiny appearance of the tongue with loss of papillae |
| Gums | pink color, firm | inflammation, swollen, and bleeding |
| Hair | healthy scalp, shiny hair | fragile, thin, and sparse hair |
| Skin | smooth, color appropriate to ethnicity | rough, flaky, swollen, pale or yellowish appearance |
| Nails | pink | spoon nails, brown-gray nails |
| Skeleton/extremities | erect normal posture, no tenderness | bowed legs, weakness, tenderness |
| Abdomen | flat | swollen |
Access additional information to educate patients on healthy dietary patterns. The guidelines were developed by the U.S. Department of Agriculture (USDA) and the U.S. Department of Health and Human Services (HHS) to provide recommendations on healthy eating, and thus promote healthas well asprevent chronic illness. This guidelines include recommendations from birth through older adulthood, and also women who are pregnant or in breastfeeding.
Knowledge Check
V. Documentation of Assessment Findings
Sample Narrative Documentation
Patient was admitted with peptic ulcer this morning. Continues to experience decreased appetite and intermittent epigastric pain, rates 2 on 0-10 pain scale currently. Abdomen soft, distended, and tender to touch. Normal bowel sounds in all 4 quadrants. No bowel movement for 2 days. Pale skin color, warm, dry. Lips pale, oral mucosa moist and intact. Afebrile, BP 110/68, P 100, R 22. Denied shortness of breath. Clear lung sounds bilaterally. No acute distress. Declined pain medication. IV D5W in Left forearm at 50 mL/hr. NPO, wait for the scheduled upper endoscopy procedure.
VI. Related Laboratory and Diagnostic Procedures/ Findings
Nutritional assessment is an ongoing process for hospitalized patients. Through the assessment findings, if the patient is suspected to have nutritional concerns such as inadequate oral intake or poor wound healing, further diagnostic and laboratory tests may be proceeded to uncover the underlining causes and provide nutritional support.
Some laboratory results can be reviewed to determine the patient’s nutritional status. Serum albumin and prealbumin levels can be used to decide the patient’s protein requirements. Electrolytes (such as serum calcium, magnesium, phosphorous), blood urea nitrogen (BUN), and creatinine can be evaluated to assess the patient’s overall fluid volume status and the need for parental nutrition. If diet-related non communicable diseases or metabolic diseases are suspected, glucose and lipid levels may be assessed. Transferrin is a protein that transports iron through the blood to different tissues and organs. Serum transferrin levels may indicate protein status. Low transferrin may indicate iron deficiency and cause anemia. In evaluation of anemia, Complete blood count (CBC), serum iron level, serum vitamin B12 and folate levels will also be checked. Blood tests for specific vitamin deficiencies may be necessary in patients who have gastrointestinal malabsorption (Hinkle & Cheever, 2018).
Click the link to access additional nutritional assessment OERs: Nutrition.
VII. Learning Exercises
VIII. Attribution and References
- Centers for Disease Control and Prevention. Healthy Weight, Nutrition, and Physical Activity: About adult BMI. Available at https://www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/index.html#InterpretedAdults
- Ernstmeyer, K., & Christman, E. (Eds.). (2021). Open RN Nursing Fundamentals by Chippewa Valley Technical College is licensed under CC BY 4.0.
- Hinkle, J. L. & Cheever, K. H. (2018). Brunner & Suddarth’s Textbook of Medical-surgical Nursing. (14th ed.). Philadelphia, PA: Wolters Kluwer.
- National Heart, Lung, and Blood Institute. Calculate Your Body Mass Index. Available at https://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm
- U.S. Department of Agriculture and U.S. Department of Health and Human Services.Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. Available atDietaryGuidelines.gov
- World Health Organization. Malnutrition. 9th June 2021. Available at https://www.who.int/news-room/fact-sheets/detail/malnutrition.
