Water balance throughout the adult life span in a German population.

Mild dehydration, defined as a 1-2% loss in body mass caused by fluid deficit, is associated with risks of functional impairments and chronic diseases. Whether water requirements change with increasing age remains unclear. Therefore, the aim of the present investigation is to quantify hydration status and its complex determining factors from young to old adulthood to analyse age-related alterations and to provide a reliable database for the derivation of dietary recommendations.

Long-term high urinary potential renal acid load and low nitrogen excretion predict reduced diaphyseal bone mass and bone size in children.

Background: Longitudinal diet assessment data in children suggest bone anabolic effects of protein intake and concurrent catabolic effects of dietary acid load. However, studies using valid biomarker measurements of corresponding dietary intakes are lacking.

Objective: The aim of the study was to examine whether the association of long-term dietary acid load and protein intake with children's bone status can be confirmed using approved urinary biomarkers and whether these diet influences may be independent of potential bone-anabolic sex steroids.

Prepubertal healthy children's urinary androstenediol predicts diaphyseal bone strength in late puberty.

Context: During the physiological process of adrenarche, the adrenal glands of healthy children secrete increasing amounts of weak androgenic steroids partly metabolized to potent sex steroids.

Objective: The aim of the study was to examine whether adrenal androgen metabolite excretion rates before the onset of puberty may be prospectively associated with late-pubertal diaphyseal bone strength.

Setting: We conducted the study in an auxological and metabolic child nutrition research facility.

Food composition and acid-base balance: alimentary alkali depletion and acid load in herbivores.

Alkali-enriched diets are recommended for humans to diminish the net acid load of their usual diet. In contrast, herbivores have to deal with a high dietary alkali impact on acid-base balance. Here we explore the role of nutritional alkali in experimentally induced chronic metabolic acidosis.

Hydration in children.

Water supply is a basic public problem. In modern science, three periods with different approaches to define recommended water intake in adults can be distinguished. Pediatricians agree that hydration in children may be optimal only in breastfed infants.