Episode 102: This is a sample of the Master the USMLE audio program online at MMC.works

NUTRITION
I. Eating disorders – includes obesity, anorexia, bulimia

Difference between anorexia and bulimia?
A. Anorexia
Distorted body image; women with anorexia can have distorted image; control issue; they have lost control of everything in their life, and the only thing that they can control over is what they put in their mouth. With a decrease of body fat and wt, GnRH decreases, therefore FSH and LH also decrease, leading to low estrogen; as a result, amenorrhea occurs, AND predisposes to osteoporosis, as if pt is postmenopausal.  Anorexic people will eventually develop osteoporosis. Rx – convince person to gain enough wt to bring period back; not birth control. (ie first step in management of HP/diabetes = wt loss; as you lose adipose,  you upregulate insulin resistance). In anorexia, usually die to cardiac dz (heart failure: heart just stops).
B. Bulimia Nervosa
1. Metabolic Alkalosis: It’s not a body image problem – they can be obese, normal or thin (no weight issue); however, they binge (eat a lot), then force themselves to vomit. Pic on boards: from vomiting, wear down enamel on teeth; so, brownish stuff seen on teeth is just dentine (erosions seen on teeth). Metabolic alkalosis from forced vomiting will be seen. Metabolic alkalois is bad b.c there is a left shift curve, and the compensation is resp acidosis, which drops pO2, therefore will get hypoxia with metabolic alkalosis, and the heart do not like that. The heart already with low O2 will get PVC’s (pre-mature ventricular  contractions), R-on-T phenomenon, then V-fib, then death. Therefore, met alkalosis is very dangerous in inducing cardiac arrythmias, and this commonly occurs in bulimics due to forced vomiting. Pt can also vomit out blood – Mallory Weiss Syndrome – tear in distal esophagus or proximal stomach.

2. Borhave syndrome, which is worse. In the syndrome, there is a rupture and air and secretions from the esophagus get into the pleural cavity; the air will dissect through subcutaneous tissue, come around the anterior mediastinum, which leads to Hemimans crunch – observed when dr looks at pt’s chest, puts a stethoscope down, and you hear a ‘crunch’. The “crunch” is air that has dissected through interstial tissue up into the mediastinum, indicating that a rupture occurred in the esophagus; this is another common thing in bulimics. So, there are 2 things imp in bulimics: 1) Metabolic alkalosis from vomiting (which can induce arrthymias 2) Borhave’s syndrome
C. Obesity
With obesity, using a diff method: BMI: kg’s in body wt/meters in body ht’2. If your BMI is 30 or greater, you are obese; if your bmi is 40 or greater, you are morbidly obese. Main complication of obesity = HTN; with HTN, leads to LVH, and potentially heart failure. MCC death in HTN = cardiac dz. Other complications of obesity include: gallbladder dz, cancers with a lot of adipose, you aromatize many  17-ketosteroids like androstenedione into estrogens. Therefore, will hyperestrinism (all obese women have hyperestrinism), you are at risk for estrogen related cancers – ie breast cancer, endometrial carcinoma, colon cancer.
II. Malnutrition
Protein-calorie malnutrition:
1. Marasmus – total calorie deposition, and wasting away of muscle; however, high chance of survival if they get food

2. Kwashiorkor – prob gonna die; have carbs, but no protein; also have anemias, cellular immunity probs (ie no rxn to ags), low albumin levels, ascites, fatty livers. These kids are apathetic and need to be  force-fed; therefore, kid with kwashiorkor is more likely to die than child with Marasmus. Example: kid with edema, flaky dermatitis, reddish hair (Cu def) – kwashiorkor
III. Vitamins
A. Difference between fat and water soluble vitamins:
1. Fat soluble vitamins dissolve in fats, indicating that they are taken up by chymlomicrons. The chymlomicron will have A, D, E, and,