Relative bioavailability of calcium from calcium formate, calcium citrate, and calcium carbonate.
Calcium is an essential nutrient required in substantial amounts, but many diets are deficient in calcium making supplementation necessary or desirable. The objective of this study was to compare the oral bioavailability of calcium from calcium formate, a new experimental dietary calcium supplement, to that of calcium citrate and calcium carbonate. In a four-way crossover study, either a placebo or 1200 mg of calcium as calcium carbonate, calcium citrate, or calcium formate were administered orally to 14 healthy adult female volunteers who had fasted overnight. After calcium carbonate, the maximum rise in serum calcium ( approximately 4%) and the fall in serum intact parathyroid hormone 1-84 (iPTH) (approximately 20-40%) did not differ significantly from placebo. After calcium citrate, the changes were modestly but significantly (p < 0.05) greater, but only at 135 to 270 min after ingestion. In contrast, within 60 min after calcium formate serum calcium rose by approximately 15% and serum iPTH fell by 70%. The mean increment in area under the plasma concentration-time curve (0-270 min) for serum calcium after calcium formate (378 mg . min/dl) was double that for calcium citrate (178 mg . min/dl; p < 0.01), whereas the latter was only modestly greater than either placebo (107; p < 0.05) or calcium carbonate (91; p < 0.05). In this study, calcium formate was clearly superior to both calcium carbonate and calcium citrate in ability to deliver calcium to the bloodstream after oral administration. Calcium formate may offer significant advantages as a dietary calcium supplement. (+info)
Reduction of adipose tissue and body weight: effect of water soluble calcium hydroxycitrate in Garcinia atroviridis on the short term treatment of obese women in Thailand.
Fifty obese women with a body mass index (BMI) over 25 kg/m(2) were randomly allocated into two groups, 25 in each. Group 1, with a mean (+/-SEM) age of 40.0+/-2 years, received water soluble calcium hydroxycitrate (HCA) as Garcinia atroviridis. Group 2, with a mean age of 35.6+/-1.8 years, received placebo. All subjects were recommended a similar diet with 1000 Kcal/day. The trial lasted for 2 months. At baseline the means BMI of Group 1 and Group 2 were 27.5+/-0.2 kg/m(2) and 26.7+/-0.5 kg/m(2), respectively. Group 1 lost significantly more weight (2.8 vs. 1.4 kg, p<0.05) and at a greater rate than Group 2 throughout the study. The decrease in their body weight was due to a loss of fat storage as evidenced by a significant decrease in the triceps skin fold thickness. On a short-term basis, HCA in Garcinia atroviridis was an effective for weight management. (+info)
The decline in hip bone density after gastric bypass surgery is associated with extent of weight loss.
Intravenous ibandronate or sodium-fluoride--a 3.5 years study on bone density and fractures in Crohn's disease patients with osteoporosis.
BACKGROUND AND AIM: Osteoporosis commonly afflicts Crohn's disease (CD) patients. Management remains unclear, with limited results for intravenous (i.v.) bisphosphonates and a follow-up longer than one year. Intravenous bisphosphonates bypass gastrointestinal-tract irritation offering an interesting alternative suitable for CD patients. We tested the long-term efficacy and safety of colecalciferol and calcium with sodium-fluoride or i.v. ibandronate for osteoporosis in CD. METHODS: 66 CD patients with lumbar osteoporosis (T-score<-2.5) were randomized to receive colecalciferol (1000 IU), calcium-citrate (800 mg) and intermittent sustained-release sodium-fluoride (50 mg) [groupA, n=33] or i.v. ibandronate (1 mg/3-monthly) [groupB, n=33]. Dual-energy X-ray absorptiometry of the lumbar-spine and right femur and X-rays of the spine were performed at baseline and after 1.0, 2.25 and 3.5 years. Fracture-assessment included visual reading and quantitative morphometry of X-rays. RESULTS: 55 (83.3%) patients completed at least the 1st year available for intention-to-treat (ITT) analysis, 42 (63.6%) completed the 2nd and 35 (53.0%) the 3rd year available for per-protocol analysis. Lumbar T-score increased by +0.23+/-0.43 (95%CI: 0.057-0.407, p<0.05), +0.71+/-1.05 (95%CI: 0.193-1.232, p<0.001) and +0.73+/-0.82 (95%CI: 0.340-1.336, p<0.001) (group A), and +0.28+/-0.41 (95%CI: 0.132-0.459, p<0.05), +0.43+/-0.55 (95%CI: 0.184-0.671, p<0.01) and +0.51+/-0.74 (95%CI: 0.145-0.882, p<0.001) (group B) during 1.0, 2.25 and 3.5 years follow-up time. In 2.71 years of follow-up, with the ITT analysis, the lumbar T-score increased by +0.66+/-0.97 (group A, p<0.001) and +0.46+/-0.67 (group B, p<0.001). One vertebral fracture with sodium-fluoride was not enough to detect differences between groups and the study was not powered for this. Study medication was well-tolerated and safe. CONCLUSIONS: Sodium-fluoride and i.v. ibandronate improved osteoporosis. Keeping in mind bisphosphonates as a standard of osteoporosis care that reduce fracture-rate, data we do not have for sodium-fluoride, CD patients with osteoporosis can be treated safely with i.v. ibandronate. (+info)