Sir

There may be disagreement about whether the words “scientifically proven” should be used to sell books (“A recipe for trouble” Nature 438, 1052; 2005). However, we have published widely on the subject of high-protein diets and our findings are broadly similar to those of other research groups who have shown better health outcomes on this kind of diet (see, for example, D. K. Layman et al. J. Nutr. 133, 411–417; 2003, and A. Due et al. Int. J. Obes. Relat. Metab. Disord. 28, 1283–1290; 2004).

High-protein diets have been criticised for their potential to cause renal and bone disease (J. Eisenstein et al. Nutr. Rev. 60, 189–200; 2002) and the red-meat component has been linked to colorectal cancer (A. Chao et al. J. Am. Med. Assoc. 293, 172–182; 2005), but the evidence is contradictory.

As The CSIRO Total Wellbeing Diet was for a general readership and covered a range of topics, we did not report an extensive review of the literature on high-protein diets. Our own work has focused not just on reduction of body fat but on reduction of lipids, glucose, insulin and blood pressure and minimization of lean-tissue loss. In our opinion, the high-protein, moderate-carbohydrate approach is superior in all these respects. We do not agree with the view reported in your News story (“Diet book attacked for its high-protein advice” Nature 438, 1060; 200510.1038/4381060b) that the CSIRO diet could lead to more breast cancer and prostate cancer.

You discuss the support we receive from the Australian meat and dairy industries. These industries funded two out of the five weight-loss studies we have performed with this protocol. These protocols were investigator-devised and controlled; the funding bodies had no input into the reports and papers. Certainly they capitalized on the positive results, as is their right.