1. Investigations and clinical research are normally carried out in developed, rich countries like America and Europe... but only on things that are within their culture and their lifestyle. No one carries out research on diets or practices or lifestyles that are present in Asia, middle east or other places. These are usually disregarded...unless they start impacting western lifestyles significantly (like Yoga).

Some papers have been published now in the west on the benefits of fasting...though it is a common practice in India for centuries but in the west was laughed at till recently as a poverty driven practice.

2. In countries like India there is very little interest and scarce resources to carry out such formal research on all the hundreds of traditional diets, customs and medical practices. Where are the sponsors, professionals and other resources? Many day to day practices, diets, food items are continued to be used on the basis of either traditional authority or anecdotal evidence and no one looks around for formal clinical research reports.

3. In all countries, even in the UK I am sure, many traditional practices, customs and methods are still prevalent among the people, though no formal research has been conducted on these or their efficacy established beyond doubt. It is impossible to establish such matters beyond doubt in all cases. Who will sponsor the research?

4. Even in areas where formal research has been conducted and results published, one cannot be too sure of the correctness of the results. We have seen how oils and fats were rejected by doctors for decades (much against common wisdom) but are suddenly today being touted as healthy. Even the much talked about good cholesterol vs bad cholesterol issue, which formed the basis of most medical diagnosis....is now under review with many experts saying that cholesterol is not responsible for heart problems.

So...what really is all this research worth?!