Home Search Sitemap Contact Bookmark

Free Dissertations - Health Dissertations

The First Points To Consider Are The Shortcomings Of The Trials Themselves. ...



The first points to consider are the shortcomings of the trials themselves. Many of them are cross sectional studies and therefore cannot, by definition, either establish or prove causal relationships. There is an intrinsic difficulty in persuading populations to give accurate records with regard to their diets as there is a great tendency to underreport intake, especially alcohol. (Guallar-Castillon P et al. 2001). This phenomenon is related to social class and many of the studies make no enquiries as to the social class of the respondents.

There is also evidence to suggest that educational status is reflected in the accuracy of completion of the dietary record and this has not been addressed in any of the major studies in the area.

Electrolytes are seldom specifically enquired for or recorded with any degree of accuracy. None of the studies seen actually enquired about the levels of sodium in the diet and there is considerable evidence that sodium intake has a negative impact on the overall morbidity from cardiovascular disease. ( Law M R et al. 1998).

More salient arguments are advanced by authorities such as Jongbloet (P H 2003) who takes an overview of the various studies that have considered the effects of the Mediterranean Diet and points out that in three of the four case controlled studies that have recently been published that have explored the putative link between olive oil consumption and cardiovascular disease there was no support found for the suggestion that there was a strong inverse relationship between the two and the only one that did find a strong relationship was based in Spain (Fernández J E et al. 2002)

In the literature one can find references to the French, Albanian and Italian paradoxes where studies point to populations who paradoxically have large quantities of saturated fats mainly in the form of butter, cheese and various other milk products and still have unusually low incidences of cardiovascular disease. (Gjonça A et al. 1997). Various authorities have therefore suggested that the focus of attention should not necessarily be the olive or the diet, but wider, as yet unidentified, factors that may affect the lifestyle. For example one could postulate that the geographical factors which are common to the geographical distribution of the olive tree are actually the relevant factors. (Grimes D S et al. 1998). Many countries exhibit a South to North gradient in the prevalence of cardiovascular disease (viz UK and France) (Lang T et al. 1999) and this has not been satisfactorily explained. There are differential cardiovascular disease incidences (and similarities) between countries at different latitudes. One should not be surprised at such postulations as they have already been established for geographical gradients in disease processes as disparate as schizophrenia, (Gupta S et al.


Thanks