If you wish to get a better understanding of he rigour of Patrick Holford’s work and how many food myths are perpetuated by vitamin pill entrepreneurs then I suggest you read the book Bad Science by Ben Goldacre.

So many people today eat food which is nutritionally deficient – it’s possible, for the first time in history, to stuff your face all day and yet to consume ZERO vitamins or minerals. Many people are totally malnourished and – guess what – this severely compromises their health! Depression, diabetes, obesity, heart disease, eczema, asthma etc. etc. – look around you folks! Are we healthier than we used to be or not?

If you are interested in Holford and what he say about diabetes then I would suggest you read here and watch the video.

http://holfordwatch.info/holford-myths/myth-the-scientific-support-for-chromium-and-cinnamon/

The Davis paper is here. (always good to give references – have you read the paper?)

Most noticeably, Davis makes it quite clear – “our study is not useful for estimating possible effects on dietary intakes”. This is exactly what you have done by being selective and over-interpretive.

The study has severe limitations. For example, it is stated that “We focused on one class of foods and an interesting biological phenomenon, without selecting foods based on their national consumption or contribution to nutrient intakes.” And so any comment on the consequences of nutritional intake is futile.

More seriously, their analyses only take into account random errors. No corrections for systematic biases are made – and this is made clear. Over fifty years – you might expect some big biases to creep in in analytical measurements. They suggest their results may well be best explained by different cultivars used 50 years apart.

Cautiously, they add that if there are real differences in staples being depleted, then a change in diet may be the best course – not vitamin pills. Reassuringly they close with a statement showing how implausible severe depletion of nutrients is: “Plant cells require most human nutrients for their own functioning. They cannot grow, much less be viable commercial food crops, without synthesizing or acquiring their own needed levels of a broad range of nutrients. Thus, no whole plant food can be as broadly depleted of nutrients as are refined sugars and separated fats and oils.”

In summary, the evidence from this paper that there is a serious depletion in the nutritional content of food is very weak and there are better explanations for the results than an implausible catastrophic reduction.

You conclude with some bizarre reference to religious belief. Not everyone is superstitious you know. My post above shows that nutritional therapy has much in common with daft superstitious belief. Both are selective in their view of evidence and unable to respond to criticism and scientific scrutiny.