Effects of supplemental dietary calcium on quantitative and qualitative fecal fat excretion in man.

Oral calcium supplementation is thought to be a useful interventional agent to decrease colon cancer risk. This is supposedly due, at least in part, to the binding of bile acids and fatty acids by calcium in the colon, thus prohibiting the damaging effects of these substances to the epithelium. To determine the effects of calcium supplementation on fecal fat excretion, 24 subjects kept a fat and calcium constant diet for one week and were supplemented with either 0, 2 or 4 g elemental calcium as calcium carbonate in a double-blind fashion. At the end of the week 72-hour feces was collected, and total fat, neutral fat, fatty acids and the ratio of polyunsaturated and saturated fatty acids (P/S ratio) were measured. Calcium dose-dependently increased the percentual excretion of total fat as related to fat intake: 6.8 +/- 0.9% during 0 g, 7.4 +/- 1.0% during 2 g and 10.2 +/- 1.4% during 4 g, r = 0.44, p = 0.03. This was due to increased fatty acid excretion, excretion of neutral fat was not affected, nor was the P/S ratio. It is concluded that calcium supplementation modestly increases fecal fatty acid excretion. No adverse metabolic effects are to be expected from this in case of long-term calcium supplementation in subjects at increased risk for colon cancer.

Effects of oral calcium supplementation on intestinal bile acids and cytolytic activity of fecal water in patients with adenomatous polyps of the colon.

Calcium has been proposed to prevent colon cancer in subjects at risk for this tumour. This effect is supposed to be due at least in part to binding the bile acids to calcium, making them insoluble and harmless. To evaluate the effects of oral calcium supplementation on intestinal bile acids, 19 patients with adenomatous colonic polyps were supplemented with 35.5 mmol Ca2+ daily for 12 weeks. Duodenal bile, 24-h feces and 24-h urine were collected before and at the end of the 12-week period. In duodenal bile proportional concentration of cholic acid increased (38 +/- 4 vs. 51 +/- 3%, P < 0.001), whereas that of chenodeoxycholic acid decreased (35 +/- 3 vs. 25 +/- 2%, P < 0.01). Total fecal bile acid excretion increased (950 +/- 126 vs. 1218 +/- 137 mumol 24 h-1, P < 0.01), with proportional concentrations of the main primary and secondary bile acids remaining the same. Cytolytic activity of fecal water, measured by the degree of lysis of erythrocytes by the water, decreased (45 +/- 8 vs. 30 +/- 7%, P < 0.05). Total excretion of calcium increased as expected from the supplementary dose. It is concluded that calcium supplementation markedly affects intestinal bile acids and lytic activity of fecal water and that, in view of similar results during 1-week calcium supplementation in young healthy subjects, these effects remain constant over at least 3 months and occur both in healthy persons and in patients at increased risk for colon cancer.

Hyperalimentation in autologous bone marrow transplantation for solid tumors. Comparison of total parenteral versus partial parenteral plus enteral nutrition.

Recipients of autologous bone marrow transplantation (ABMT) for solid tumors need nutritional support to maintain their body weight (BW). Severe BW-reduction (9.9%) was noticed retrospectively in ten ABMT patients fed orally, despite intensive counseling or occasional tube feeding. A prospective, randomized study of hyperalimentation (25 g nitrogen (N) and 3400 nonprotein kilocalories) with total parenteral nutrition (TPN) or partial parenteral plus enteral nutrition by tube feeding (PPN/EN) was done in 22 patients. Nutritional assessment included balance measurements of N, Na, K, Cl, P, Ca, Mg, Cu, and Zn, and serial measurements of BW, serum albumin, prealbumin, and transferrin. Both regimens were effective in maintaining BW (maximum percent of change, 2.5) and N-balance. Blood products accounted for an additional N-intake of 13% in both groups. The TPN group had a higher dietary N-intake versus PPN/EN, a positive K balance but negative Ca, Mg, Cu, and Zn balances. More mineral supplementation was given in the PPN/EN group where positive K, Mg, and Zn balances were seen. Visceral proteins and IgG, IgA, and IgM levels were decreased on days 7, 14, and 21. Creatinine clearance increased significantly in both groups. Compared with TPN, the PPN/EN group showed a twofold number of patients with a positive blood culture, although this observation did not reach statistical significance and patients had fewer days of diarrhea (31.1% versus 54.3%, P less than 0.01). Hyperalimentation with PPN/EN is an acceptable alternative to TPN in the nutritional support of ABMT recipients.