Heavy consumption of the essential amino acid lysine (as indicated in the treatment of cold sores) has allegedly shown false positives in some and was cited by American shotputter C. J. Hunter as the reason for his positive test, though in 2004 he admitted to a federal grand jury that he had injected nandrolone.  A possible cause of incorrect urine test results is the presence of metabolites from other AAS, though modern urinalysis can usually determine the exact AAS used by analyzing the ratio of the two remaining nandrolone metabolites. As a result of the numerous overturned verdicts, the testing procedure was reviewed by UK Sport . On October 5, 2007, three-time Olympic gold medalist for track and field Marion Jones admitted to use of the drug, and was sentenced to six months in jail for lying to a federal grand jury in 2000. 
Endogenous corticosteroids are secreted by the adrenal cortex; their effects are believed to be due to modification of enzymatic activity rather than to a direct hormone-induced action. Fludrocortisone mimics the actions of aldosterone, an endogenous mineralocorticoid. Mineralocorticoids facilitate sodium resorption and promote hydrogen ion and potassium excretion at the level of the distal renal tubule. Small oral doses produce marked sodium retention and increased urinary potassium excretion. Among 5 adults with orthostatic hypotension who took fludrocortisone —1 mg/day for 10—14 days, the change in sodium balance ranged from +149 mmol to +282 mmol, and the change in plasma volume ranged from 185 ml to 299 mL. The mean recumbent blood pressure increased from 110 +/-6 over 69 +/-3 mmHg to 124 +/-7 over 79 +/-2 mmHg. Although fludrocortisone receipt tended to decrease the signs and symptoms of severe orthostatic hypotension, only incomplete symptomatic relief was obtained in each patient. Larger doses can inhibit endogenous adrenal cortical secretion, thymic activity, and pituitary corticotropin excretion; promote the deposition of liver glycogen; and, if protein intake is inadequate, induce negative nitrogen balance.
Fludrocortisone receipt (—1 mg/day) for at least a year led to recumbent and standing blood pressure increases in all 7 adults with severe orthostatic hypotension; 5 had idiopathic disease and 2 had orthostatic hypotension associated with diabetes. Average systolic blood pressure values were at least 20 mmHg higher and average diastolic blood pressure values were at least 10 mmHg higher as compared with values before fludrocortisone receipt. Hypertensive retinopathy developed in 2 patients; one of the 2 patients also had x-ray evidence of cardiomegaly and electrocardiographic changes consistent with left ventricular hypertrophy. Although plasma volume increased over the first 10 days of fludrocortisone receipt, the plasma volume decreased to control levels despite further blood pressure increases. Treatment did not affect plasma catecholamines concentrations and did not enhance pressor response to infused norepinephrine in 5 patients who had hyperreactive blood pressure responses to norepinephrine before fludrocortisone receipt. An enhanced pressor response to infused norepinephrine occurred in 2 patients who showed normal blood pressure responses to norepinephrine before fludrocortisone receipt. Hemodynamic data were obtained from 2 patients; hypertension in the recumbent position was related to increases in total peripheral vascular resistance - no appreciable change in either cardiac output or plasma volume was noted.
Although I am usually not inclined to posit speculations on why a particular drug does or doesn't do something, in this case I will. Im guessing that the higher doses of Anadrol cause enough appetite suppression (at least anecdotally) to make eating rather difficult. It can also increase insulin resistance and glucose intolerance (5). This has the effect of making macronutrient absorption more inefficient, and could also be a factor in reducing gains when the dosage goes over 100mgs/day. Unfortunately, Anadrol also has a reasonably profound effect on your body's natural hormonal system, on par with most other oral steroids , but not as bad as most injectables, and its certainly not as harsh on your lipid profile as many anabolics are