No abstract

These findings suggest that changing the gastric pH alone does not modify the net intestinal absorption of several minerals from food. Therefore, it is unlikely that moderate hypochlorhydria resulting from short-term omeprazole treatment substantially increases the risk for developing calcium, phosphorus, magnesium, or zinc deficiencies due to mineral malabsorption.

Phytosterols, found in fat-soluble fractions of plants, chemically resemble cholesterol and inhibit cholesterol absorption in the small intestine. Phytosterol consumption in human subjects reduces plasma total and low density lipoprotein-cholesterol (LDL-C) levels. The primary aim of this study was to determine the efficacy of a low-fat spread enriched with plant sterols in reducing total and LDL-C concentrations in primary hypercholesterolemia. The secondary objective was to evaluate whether patients receiving a lipid-lowering drug (fibrate) might differ in their response to plant sterols. The study was a randomized, double-blind, placebo-controlled two-period cross-over trial with two treatments and three periods. Both treatment periods lasted 2 months, with a washout period (2 months) between them. Spread enriched with plant sterols was compared to non-enriched control spread. Fortified fat spread provided 1.6 g/day of plant sterols derived from edible vegetable oils and fatty acids from sunflower seed oil. The plant sterol content consisted of sitosterol esters (50%), campesterol esters (25%), stigmasterol esters (20%) and 10% of other esters. Data in 53 hypercholesterolemic patients (31 females and 22 males) who completed the study were as follows: patients were 58+/-12 years of age with mean body mass index 23.5+/-2.8 kg/m2 (mean+/-SD). No adverse side-effects of the diet were reported. Plasma total cholesterol and LDL-C concentrations were significantly reduced by 6.4% and 8.8%, respectively, after using the spread enriched in plant sterols, as compared to controls (0.0% and 1.3%, respectively). No effect on high density lipoprotein-cholesterol (HDL-C) and lipoprotein(a) concentrations was detected. When subjects were divided in two subgroups according to fibrate treatment, supplementation with phytosterols decreased plasma cholesterol and LDL-C by 8.5% and 11.1%, respectively in the subgroup of patients treated with fibrates. In the group of patients who did not receive fibrates, consumption of plant sterol margarine reduced plasma cholesterol and LDL-C by 5.5% and 7.7%, respectively. Spread enriched with plant sterol esters significantly lowers blood total and LDL-C levels without affecting HDL-C concentrations, in a hypercholesterolemic population following a strict low cholesterol diet (NCEP step1). In addition, a combination of fibrate treatment and plant sterol ester-supplemented spread offers a safe and effective measure to significantly decrease abnormally high cholesterol levels. We conclude that phytosterol-enriched spread is a useful adjunctive therapy for hypercholesterolemic patients.

The deleterious effects of increased gastric pH on calcium absorption from calcium carbonate supplements were observed about 25 years ago. Increasing use of calcium supplements, especially by the elderly, has raised questions about bioavailability from various calcium sources. Decreased gastric acidity is common in the elderly and in patients taking antiulcer medications. A critical review of the available human studies that have investigated the role of gastric acidity in calcium bioavailability suggests that the effects of increased gastric pH are only apparent when poorly soluble calcium salts are taken after an overnight fast. Soluble calcium sources, such as calcium citrate and calcium from milk, are absorbed normally in elderly subjects with atrophic gastritis. Moreover, calcium carbonate, a relatively insoluble calcium salt, is well absorbed in atrophic gastritis patients if administered with a meal. In order to maximize calcium bioavailability, elderly subjects should increase their calcium intakes to at least recommended levels, preferably by increasing milk consumption. When calcium supplements are used to augment dietary calcium sources, a highly soluble source should be of benefit or calcium carbonate may be taken with a meal.