Acid-Base and the Skeleton

Summary

The evidence base for the health-related benefits of a high consumption of fruit & vegetables for chronic disease prevention continues to expand in relation to ischaemic heart disease; stomach, bowel and breast cancer and most recently for stroke reduction. For osteoporosis, there is a strong evidence-base from a combination of observational, experimental, clinical and intervention studies which point to a positive link between fruit & vegetable consumption and indices of bone health.

Future research should focus attention on (i) long-term intervention trials centred specifically on fruit & vegetable intake/alkali administration as the supplementation vehicle and assessing a wide range of bone health indices (including fracture risk); (ii) experimental studies (at both the cellular, animal and human level) to determine whether there are other aspects of fruit & vegetables which are beneficial to bone metabolism and under what mechanisms .

This project focuses on two aspects: (1). Estimation of the intake of dietary acidity and alkalinity in the British population using the NDNS datasets; (2) the effects of the Atkins diet ,in comparison to a high fruit & vegetable weight loss diet, on markers of bone metabolism in men.

Project Status : November 2008

The analysis of the NDNS datasets are now complete and the findings for the 65+ years population group has been published in the British Journal of Nutrition.

The data collection for the Atkins diet is now complete and the analysis of the data is underway, with a view to publication in early 2009.

Dr Richard Gannon has been successful in gaining his PhD.

Project Objectives

Our key objectives are:

1. To estimate the acid/alkaline generating potential of the diet by quantifying estimates of NEAP using PRAL and Protein/Potassium algorithms in a representative group of British elderly men and women using NDNS datasets.
2. To quantify dietary acidity characteristics of the Atkins diet vs. a high fruit & vegetable weight loss group by estimates of NEAP.
3. Determine the short-term (6 months) effects of the Atkins diet vs. a high fruit & vegetable weight loss group on markers of bone metabolism.

Results and Findings

Gannon RHT., Millward DJ., Macdonald HM., Frassetto LA., Remer T., Lanham-New SA. Estimates of net acid excretion indirectly (NAEind) and net rate of endogenous non-carbonic acid production (NEAP) in the elderly UK population: analysis of the National Diet and Nutrition Survey (NDNS) of British adults aged 65 years and over. Brit J Nutr 2008;100:615-623.

Lanham-New SA & Gannon RHT. (2007) Protein, potassium and fruit and vegetable influences on bone health: an update on current thinking. In: Prevention and Treatment of Osteoporosis. Eds Lanham-New SA, O’Neill T, Sutcliffe A & Morris R. Clinical Publishing, Oxford. 2007.

Vokes L, Gannon RHT, Millward DJ, Lovell DP, Macdonald HM, Frassetto LA, Remer T & Lanham-New SA (2007) Estimates of net acid excretion indirect (NAEind) and net rate of endogenous non-carbonic acid production (NEAP) in the young British population: analysis of the National Diet and Nutrition Survey (NDNS) aged 4-18 years. Proceedings of the Nutrition Society. 2007.