Effects of a salt-restricted diet on the intake of other nutrients.

BACKGROUND: Salt restriction, recommended as the first-line treatment of hypertension, has been proposed to lead to deficiencies in intakes of some other nutrients. OBJECTIVE: The aim of this study was to investigate the effects of salt restriction for 20 wk on the intake of other nutrients in free-living subjects with mildly elevated blood pressure. DESIGN: Thirty-nine subjects (24 men, 15 women) aged 28-65 y with a mean daytime ambulatory diastolic blood pressure of 90-105 mm Hg and a diastolic blood pressure measured in a health care center of 95-115 mm Hg participated in the study. The subjects completed 4-d food records and their salt intake was measured by 24-h urinary sodium excretion. The subjects received both oral and written instructions from a clinical nutritionist on how to reduce their daily sodium chloride intake to <5 g/d but were instructed not to change their diet otherwise. The subjects were provided with low-salt bread during the salt-restriction period. RESULTS: Few changes were found in nutrient intakes. In men, total energy intake decreased by 1059 kJ/d and alcohol, potassium, and vitamin D intakes decreased, but there were no significant changes in energy-adjusted potassium and vitamin D intakes. In women, total potassium intake increased, but the potassium density of the diet remained unchanged. Total selenium intake and energy-adjusted intake of selenium both decreased significantly in women. CONCLUSIONS: Salt restriction can be undertaken in free-living hypertensive subjects without any untoward changes in the intake of other nutrients.

Adherence to the salt restriction diet among people with mildly elevated blood pressure.

OBJECTIVE: The aim of the study was to examine the adherence to a salt restriction diet and the effect of salt restriction on blood pressure in free living subjects with mildly elevated blood pressure. DESIGN: Subjects with mildly elevated blood pressure participated in a controlled study on the effect of salt restriction on blood pressure. Subjects received oral and written instructions by a clinical nutritionist to reduce sodium chloride intake to five grams per day. A low sodium bread (0.5%) was supplied free of charge for the subjects during the whole low-sodium period (between weeks 4-24). SUBJECTS AND METHODS: Subjects were recruited from previous studies at the Kuopio Research Institute of Exercise Medicine and from local occupational health care services. Twenty-four men and 15 women aged 28-65 y with the mean daytime ambulatory diastolic blood pressure between 90-105 mmHg and office diastolic blood pressure between 95-115 mmHg were included in the study. Salt intake was monitored by 4-d food diaries and 24-h urinary sodium excretion. RESULTS: Twenty percent of the subjects achieved a urinary sodium excretion level of less than 74 mmol/24 h corresponding to a salt intake of five grams per day. There was a significant decline (7.1+/-12.7/4.2+/-7.5) in systolic and diastolic blood pressure levels during the salt restriction diet. CONCLUSIONS: Even moderate salt restriction seems to be effective in the treatment of mildly elevated blood pressure. However, the recommended salt intake level of less than five grams per day is difficult to achieve even after intensive counselling and regular use of low salt bread.

A new method with general diagnostic utility for the calculation of immunoglobulin G avidity.

The reference method for immunoglobulin G (IgG) avidity determination includes reagent-consuming serum titration. Aiming at better IgG avidity diagnostics, we applied a logistic model for the reproduction of antibody titration curves. This method was tested with well-characterized serum panels for cytomegalovirus, Epstein-Barr virus, rubella virus, parvovirus B19, and Toxoplasma gondii. This approach for IgG avidity calculation is generally applicable and attains the diagnostic performance of the reference method while being less laborious and twice as cost-effective.