Low-sodium diet may benefit bone health

November 4, 2009

A study published in the British Journal of Nutrition shows that switching to low-salt products may benefit bone health by reducing calcium loss. A randomized, parallel-design dietary intervention study was conducted in 92 women (aged 45–75 years) with prehypertension or stage 1 hypertension. The aim was to compare the effects on bone turnover of a low-sodium DASH-type diet or a high-carbohydrate low-fat diet. The former was characterized by a higher basic or alkaline load, while the latter was characterized by a higher acid load. Both diets contained 800 mg dietary calcium per day.

After 14 weeks, the researchers noted that sodium levels in the urine of the women on low-sodium diet fell by 26%, while potassium excretion increased by 6.8 millimoles (mmol) per day. Furthermore, compared to the high-carb, low-fat diet, calcium levels in the urine decreased by 0.7 mmol per day in the low-sodium diet group. Women consuming the high-carb, low-fat diet also experienced an increased rate of bone turnover, compared with women in the low-sodium group.

The researchers concluded that “It would be worthwhile to assess if a lower-acid load diet assists in maintaining bone health on a lower-calcium diet, as this is particularly relevant for older individuals who usually find it difficult to consume sufficient dietary calcium from food sources.”

Abstract