Clinical Nutrition

A 61-year-old woman presents with progressive fatigue, numbness in both feet, poor balance and difficulty concentrating. She has followed a strict vegan diet for 11 years. Her medications include: • Metformin for type 2 diabetes • Omeprazole for chronic GERD • Amlodipine for hypertension Physical examination reveals pallor, reduced vibration sensation in both feet and an unsteady tandem gait. Laboratory findings: • Hemoglobin: 10.4 g/dL • MCV: 109 fL • Serum vitamin B12: borderline low • Serum folate: normal • TSH: normal • Creatinine: normal

A 39-year-old woman presents with fatigue, exertional shortness of breath, headaches and a desire to chew ice. Her menstrual periods last eight days and are described as very heavy. She takes levothyroxine every morning for hypothyroidism. Laboratory findings: • Hemoglobin: 9.6 g/dL • MCV: 71 fL • Ferritin: 7 mcg/L • Serum iron: low • TIBC: elevated • Transferrin saturation: low

A 72-year-old woman presents with diffuse bone discomfort, proximal muscle weakness and difficulty rising from a chair. She rarely goes outdoors and consumes little dairy or fortified plant-based milk. Laboratory findings: • 25-hydroxyvitamin D: low • Alkaline phosphatase: elevated • Serum calcium: low-normal • Serum phosphate: low-normal • Renal function: normal

A 73-year-old man takes warfarin for atrial fibrillation. His INR had been stable for several months. Two weeks ago, he began drinking a large kale, spinach and parsley smoothie every morning. His INR is now below the therapeutic range.

A 48-year-old woman with primary hypothyroidism reports increasing fatigue and constipation. She takes levothyroxine each morning together with: • A calcium-fortified protein shake • An iron-containing multivitamin • A kelp supplement containing iodine Her TSH has increased despite taking the prescribed levothyroxine dose.

A 56-year-old man has type 2 diabetes, hypertension, elevated LDL cholesterol and central obesity. Current findings: • HbA1c: 8.3% • Blood pressure: 148/88 mmHg • LDL cholesterol: elevated • Triglycerides: elevated • Kidney function: normal His diet consists mainly of sweetened beverages, white bread, processed meat, fried food and restaurant meals. He takes metformin and gliclazide.

A 34-year-old woman reports chronic diarrhea, abdominal bloating, fatigue and unintentional weight loss. She has an intensely itchy, grouped vesicular rash on her elbows. Laboratory findings: • Hemoglobin: low • MCV: low • Ferritin: low • 25-hydroxyvitamin D: low Her sister has confirmed celiac disease.

A 69-year-old man has stage 3b chronic kidney disease, hypertension and heart failure. His medications include: • Lisinopril • Spironolactone • Furosemide • Metoprolol He asks whether he should use a potassium-chloride salt substitute and take an over-the-counter potassium supplement for leg cramps.

A 29-year-old woman plans to become pregnant within the next six months. She follows a vegan diet and is not currently taking supplements. She has no personal or family history of a neural-tube defect and no known malabsorptive disorder.

A 47-year-old man presents with severe unintentional weight loss following prolonged illness and alcohol misuse. Findings include: • BMI: 15.8 kg/m² • Weight loss: 17% over four months • Minimal food intake for 11 days • Generalized weakness • Low serum phosphate • Low magnesium • Low-normal potassium A family member suggests giving him several high-calorie nutritional shakes immediately.

A 58-year-old woman presents with muscle cramps, tremor, weakness and intermittent palpitations. She has chronic GERD and hypertension. Current medications: • Omeprazole for seven years • Hydrochlorothiazide • Amlodipine Physical examination reveals mild tremor and an irregular pulse. Laboratory findings: • Serum magnesium: markedly low • Potassium: 3.0 mmol/L • Corrected calcium: mildly low • Creatinine: normal • ECG: prolonged QT interval with frequent premature ventricular complexes

A 68-year-old man with coronary artery disease, atrial fibrillation and hypertriglyceridemia takes warfarin. Without discussing it with his anticoagulation clinic, he begins taking an over-the-counter fish-oil product providing approximately 4 g of EPA and DHA daily. Two weeks later, he reports increased bruising and intermittent palpitations.

A 67-year-old postmenopausal woman undergoes bone-density testing after losing 4 cm in height. Results include: • Femoral-neck T-score: −2.8 • Lumbar-spine T-score: −2.6 • 25-hydroxyvitamin D: insufficient • Renal function: normal She consumes little calcium and takes weekly alendronate at breakfast together with coffee, calcium and a multivitamin.

A 32-year-old woman reports recurrent abdominal pain, bloating and alternating constipation and diarrhea for 18 months. Her pain is related to bowel movements. She has no: • Rectal bleeding • Fever • Nocturnal diarrhea • Unintentional weight loss • Family history of inflammatory bowel disease or colorectal cancer CBC, inflammatory markers, celiac screening and thyroid testing are normal.

A 46-year-old man with poorly controlled celiac disease presents with reduced taste, poor appetite, slow wound healing, hair loss and a scaly rash around his mouth. Laboratory testing shows a low plasma zinc concentration. He takes doxycycline for rosacea and asks whether he should take 100 mg of elemental zinc daily indefinitely.

A 44-year-old woman underwent Roux-en-Y gastric bypass eight months ago. She has experienced persistent vomiting for three weeks and has been unable to tolerate her bariatric multivitamin. She now presents with: • Confusion • Unsteady gait • Horizontal nystagmus • Lower-extremity weakness • Tachycardia

A 53-year-old man with obesity and poorly controlled type 2 diabetes presents for a lipid review. Laboratory findings: • Triglycerides: 780 mg/dL • HbA1c: 9.4% • LDL cholesterol: elevated • TSH: normal • Liver enzymes: mildly elevated He drinks four beers nightly and consumes several sugar-sweetened beverages daily.

A 60-year-old woman has persistent hypertension despite taking lisinopril. Findings include: • Blood pressure: 152/92 mmHg • Potassium: normal • Creatinine and eGFR: normal • BMI: 31 kg/m² Her diet is high in canned soup, deli meat, fast food, salty snacks and frozen meals. She eats few vegetables, fruits, legumes or dairy alternatives.

A 55-year-old man develops sudden severe pain, redness, warmth and swelling of the first metatarsophalangeal joint after a weekend involving beer, organ meats and dehydration. He has obesity, hypertension and stage 2 chronic kidney disease.

A 52-year-old woman with obesity, type 2 diabetes and dyslipidemia has persistently elevated ALT and AST. She drinks alcohol only rarely. Ultrasound demonstrates hepatic steatosis. Viral hepatitis testing is negative, and her medication review does not reveal an obvious cause of liver injury.

A 27-year-old woman presents with persistent headache, nausea, dry peeling skin, hair loss and generalized bone discomfort. She takes: • Isotretinoin for severe acne • A multivitamin containing preformed vitamin A • A separate supplement providing 25,000 IU of vitamin A daily • Cod liver oil She is planning pregnancy within the next six months. Laboratory testing reveals elevated liver enzymes.

A 45-year-old woman presents with progressive burning, numbness and tingling in both feet. She has become unsteady when walking in the dark. She takes: • A “nerve support” supplement containing 100 mg of vitamin B6 • A B-complex containing 50 mg of vitamin B6 • Two fortified energy drinks daily • A multivitamin Her vitamin B12, folate, HbA1c and thyroid testing are normal.

A 62-year-old man presents with fatigue, pallor, reduced appetite and a painful smooth tongue. His diet consists largely of toast and processed foods, and he drinks six alcoholic beverages daily. Laboratory findings: • Hemoglobin: 9.9 g/dL • MCV: 112 fL • Serum folate: low • Vitamin B12: normal • Methylmalonic acid: normal • Homocysteine: elevated • Reticulocyte count: low Neurological examination is normal.

A 70-year-old woman presents with constipation, nausea, weakness, excessive thirst, frequent urination and increasing confusion. She has been taking: • Calcium carbonate antacids several times daily • A calcium supplement providing 1,500 mg daily • Vitamin D at 10,000 IU daily • Hydrochlorothiazide Laboratory findings: • Corrected serum calcium: 13.1 mg/dL • Creatinine: elevated from baseline • Bicarbonate: elevated • Parathyroid hormone: suppressed

A 41-year-old woman reports fatigue, poor sleep and difficulty concentrating during a period of significant workplace stress. An online provider diagnosed “adrenal fatigue” using a commercial salivary panel and recommended: • Adrenal glandular extract • High-dose DHEA • Licorice extract • Several stimulant-containing products Her blood pressure, sodium, potassium and morning cortisol are normal. She has no weight loss, hyperpigmentation, vomiting or orthostatic hypotension.

A 33-year-old man with Crohn’s disease underwent resection of 50 cm of terminal ileum two years ago. He now reports fatigue, numbness in his feet and increased loose stools. Laboratory findings: • Hemoglobin: 10.6 g/dL • MCV: 106 fL • Vitamin B12: low • 25-hydroxyvitamin D: low • Ferritin: low-normal • C-reactive protein: mildly elevated

A 56-year-old man with chronic alcohol-associated pancreatitis presents with weight loss, abdominal discomfort and frequent bulky, greasy, foul-smelling stools that are difficult to flush. Laboratory and clinical findings include: • Low vitamin D • Prolonged INR that corrects with vitamin K • Low body weight • Elevated HbA1c • Stool testing consistent with fat malabsorption

A 44-year-old man has passed three calcium oxalate stones during the past five years. His usual diet includes: • Very little water • High-sodium restaurant meals • Large portions of red meat • Daily spinach smoothies • Minimal calcium-containing food A 24-hour urine test shows low urine volume, hypercalciuria and elevated urinary oxalate.

A 20-year-old university student is brought to the clinic because of progressive food restriction, excessive exercise and a strong fear of gaining weight. Findings include: • BMI: 14.9 kg/m² • Heart rate: 42 beats/minute • Blood pressure: 84/54 mmHg • Orthostatic dizziness • Potassium: 2.9 mmol/L • Phosphate: low • Amenorrhea • Prolonged QT interval She states that she only needs a meal plan and does not want medical treatment.

An 82-year-old man living alone presents with weakness, recurrent falls and poor wound healing. He lost 11% of his body weight during the past three months. Contributing factors include: • Difficulty chewing • Coughing while drinking • Reduced appetite • Limited income • Social isolation • Recent hospitalization for pneumonia Findings include reduced muscle mass, low grip strength and a sacral pressure injury.

A 66-year-old man presents with fatigue, painful swollen gums, easy bruising and poor healing of a lower-leg wound. His diet consists mainly of tea, toast, processed meat and canned soup. He rarely eats fruits or vegetables. Physical examination reveals: • Gingival swelling and bleeding • Perifollicular hemorrhages • Corkscrew-shaped hairs • Scattered ecchymoses • Poor wound healing Laboratory findings: • Hemoglobin: 10.8 g/dL • MCV: 82 fL • Ferritin: low-normal • Platelets: normal • INR: normal

A 59-year-old man with type 2 diabetes and dyslipidemia begins taking an internet-purchased “cholesterol support” product containing 2,000 mg of extended-release niacin nightly. Three months later, he develops: • Facial flushing and itching • Nausea and right-upper-quadrant discomfort • Increased fasting glucose • Elevated ALT and AST • Elevated uric acid • A painful swollen first metatarsophalangeal joint He also takes atorvastatin.

A 51-year-old woman presents with nausea, fatigue, hair loss, brittle nails and a persistent metallic or garlic-like taste. She reports taking: • A multivitamin containing selenium • A thyroid-support product containing selenium • A separate 400 mcg selenium supplement • Six to eight Brazil nuts daily She began these products because she read that selenium “optimizes every thyroid condition.”

A 43-year-old woman with a history of autoimmune thyroid disease presents with palpitations, anxiety, heat intolerance and unintentional weight loss. She recently began taking: • A high-dose kelp supplement • An iodine-containing “thyroid support” formula • An iodine-containing multivitamin Laboratory findings: • TSH: suppressed • Free T4: elevated • Thyroid antibodies: positive

A 19-year-old university student develops generalized hives, lip swelling, wheezing and dizziness within 10 minutes of eating a cookie containing peanuts. A friend gives him an oral antihistamine. His symptoms continue to worsen, and his blood pressure is 82/48 mmHg. After recovery, he asks whether he should eliminate peanuts, tree nuts, dairy, eggs, wheat, soy and fish without further assessment.

A 28-year-old woman reports bloating, abdominal cramps, flatulence and loose stools after drinking milk. Her symptoms began after a severe gastrointestinal infection. She tolerates: • Small amounts of hard cheese • Lactose-free milk • Some yogurt She has no hives, wheezing, lip swelling, rectal bleeding or weight loss.

A 64-year-old man has stage 4 chronic kidney disease caused by diabetes and hypertension. Laboratory findings: • eGFR: 24 mL/min/1.73 m² • Potassium: mildly elevated • Phosphate: elevated • Bicarbonate: mildly low • Albuminuria: present His diet contains: • Processed cheese • Cola beverages • Deli meats • Packaged baked goods • Large protein shakes • A potassium-chloride salt substitute He is not receiving dialysis.

A 57-year-old man with cirrhosis presents with ascites, weakness and progressive muscle loss. His spouse has restricted his protein because she believes protein causes hepatic encephalopathy. His current pattern is: • One or two small meals daily • Less than 40 g of protein daily • Prolonged overnight fasting • Frequent canned soup and processed meat • Occasional alcohol use He has had two previous episodes of hepatic encephalopathy.

A 63-year-old man with advanced pancreatic cancer has lost 12% of his body weight over three months. He reports early satiety, altered taste, fatigue and loss of strength. His family is frustrated because he continues losing muscle despite using high-calorie shakes. They ask whether tube feeding will completely reverse the condition.

A seven-month-old boy is brought for poor weight gain. He was previously tracking near the 50th percentile for weight but has crossed downward through two major percentile curves during the past four months. His mother reports financial difficulty and prepares formula by mixing one scoop with twice the recommended amount of water so that each container lasts longer. Complementary foods consist mainly of diluted rice cereal. Findings include: • Low weight for length • Preserved head circumference • Reduced subcutaneous fat • Mild developmental delay • No vomiting, diarrhea or cardiopulmonary symptoms

A 37-year-old woman with chronic cholestatic liver disease presents with progressive difficulty walking, reduced vibration sensation and muscle weakness. Laboratory findings include: • Low serum alpha-tocopherol • Prolonged fat malabsorption • Normal vitamin B12 • Normal folate • Normal HbA1c She takes warfarin for a previous venous thromboembolism. After reading about vitamin E, she purchases a supplement providing 800 IU daily.

A 63-year-old man presents with fatigue, progressive gait instability and numbness in both legs. He has used 75 mg of elemental zinc daily for two years to “support immunity.” He also uses large amounts of zinc-containing denture adhesive. Laboratory findings: • Hemoglobin: 9.8 g/dL • MCV: 101 fL • Neutrophils: low • Vitamin B12: normal • Folate: normal • Serum copper: low • Ceruloplasmin: low

A 35-year-old woman presents to the emergency department with chest pressure and palpitations. She takes a “hair and nail” supplement containing 10 mg of biotin daily. Initial laboratory results show: • TSH: very low • Free T4: elevated • Troponin: reported as normal She has no previous thyroid disease. Her ECG shows dynamic ST-segment changes, and the clinician remains concerned about acute coronary syndrome.