Not Found
Locations

Find information on medical topics, symptoms, drugs, procedures, news and more, written for the health care professional.

* This is the Professional Version. *

Nutrition in Clinical Medicine

By Adrienne Youdim, MD, FACP, UCLA David Geffen School of Medicine, Cedars Sinai Medical Center

Click here for
Patient Education

Nutritional deficiencies can often worsen health outcomes (whether a disorder is present or not), and some disorders (eg, malabsorption) can cause nutritional deficiencies. Also, many patients (eg, elderly patients during acute hospitalization) have unsuspected nutritional deficiencies that require treatment. Many medical centers have multidisciplinary nutrition support teams of physicians, nurses, dietitians, and pharmacists to help the clinician prevent, diagnose, and treat occult nutritional deficiencies.

Overnutrition may contribute to chronic disorders, such as cancer, hypertension, obesity, diabetes mellitus, and coronary artery disease. Dietary restrictions are necessary in many hereditary metabolic disorders (eg, galactosemia, phenylketonuria).

Evaluation of Nutritional Status

Indications for nutritional evaluation include the following:

  • Undesirable body weight or body composition

  • Suspicion of specific deficiencies or toxicities of essential nutrients

  • In infants and children, insufficient growth or development

Nutritional status should be evaluated routinely as part of the clinical examination for

  • Infants and children

  • The elderly

  • People taking several drugs

  • People with psychiatric disorders

  • People with systemic disorders that last longer than several days

Evaluating general nutritional status includes history, physical examination, and sometimes tests. If undernutrition is suspected, laboratory tests (eg, albumin levels) and skin tests for delayed hypersensitivity may be done. Body composition analysis (eg, skinfold measurements, bioelectrical impedance analysis) is used to estimate percentage of body fat and to evaluate obesity.

History includes questions about dietary intake, weight change, and risk factors for nutritional deficiencies and a focused review of systems (see Table: Symptoms and Signs of Nutritional Deficiency). A dietitian can obtain a more detailed dietary history. It usually includes a list of foods eaten within the previous 24 h and a food questionnaire. A food diary may be used to record all foods eaten. The weighed ad libitum diet, in which the patient weighs and writes down all foods consumed, is the most accurate record.

Symptoms and Signs of Nutritional Deficiency

Area/System

Symptom or Sign

Deficiency

General appearance

Wasting

Energy

Skin

Rash

Many vitamins, zinc, essential fatty acids

Rash in sun-exposed areas

Niacin (pellagra)

Easy bruising

Hair and nails

Thinning or loss of hair

Protein

Premature whitening of hair

Spooning (upcurling) of nails

Eyes

Impaired night vision

Corneal keratomalacia (corneal drying and clouding)

Vitamin A

Mouth

Cheilosis and glossitis

Riboflavin, niacin , pyridoxine, iron

Bleeding gums

Vitamin C, riboflavin

Extremities

Edema

Protein

Neurologic

Paresthesias or numbness in a stocking-glove distribution

Thiamin (beriberi)

Tetany

Cognitive and sensory deficits

Thiamin, niacin , pyridoxine, vitamin B12

Dementia

Thiamin, niacin , vitamin B12

Musculoskeletal

Wasting of muscle

Protein

Bone deformities (eg, bowlegs, knocked knees, curved spine)

Vitamin D, calcium

Bone tenderness

Vitamin D

Joint pain or swelling

Vitamin C

GI

Diarrhea

Protein, niacin , folate, vitamin B12

Diarrhea and dysgeusia

Zinc

Dysphagia or odynophagia (due to Plummer-Vinson syndrome)

Iron

Endocrine

Thyromegaly

A complete physical examination, including measurement of height and weight and distribution of body fat, should be done. Body mass index (BMI)—weight(kg)/height(m)2, which adjusts weight for height (see Table: Body Mass Index (BMI)), is more accurate than height and weight tables. There are standards for growth and weight gain in infants, children, and adolescents (see Physical Growth of Infants and Children ).

Body Mass Index (BMI)

Weight Category

(BMI)

Normal* (18.5–24)

Overweight (25–29)

Obese (30–34)

Obese (35–39)

Extremely Obese (40–47)

Extremely Obese (48–54)

Height (in)

Body Weight (lb)

60–61

97–127

128–153

153–180

179–206

204–248

245–285

62–63

104–135

136–163

164–191

191–220

218–265

262–304

64–65

110–144

145–174

174–204

204–234

232–282

279–324

66–67

118–153

155–185

186–217

216–249

247–299

297–344

68–69

125–162

164–196

197–230

230–263

262–318

315–365

70–71

132–172

174–208

209–243

243–279

278–338

334–386

72–73

140–182

184–219

221–257

258–295

294–355

353–408

74–75

148–192

194–232

233–272

272–311

311–375

373–431

76

156–197

205–238

246–279

287–320

328–385

394–443

*BMIs less than those listed as normal are considered underweight.

Calculations are done using metric units (kg, m), but the table is presented in inches and pounds for US readers.

Distribution of body fat is important. Disproportionate truncal obesity (ie, waist/hip ratio > 0.8) is associated with cardiovascular and cerebrovascular disorders, hypertension, and diabetes mellitus more often than fat located elsewhere. Measuring waist circumference in patients with a BMI of < 35 helps determine whether they have truncal obesity and helps predict risk of diabetes, hypertension, hypercholesterolemia, and cardiovascular disorders. Risk is increased if waist circumference is > 102 cm (> 40 in) in men or > 88 cm (> 35 in) in women.

Resources In This Article

* This is the Professional Version. *