Taking a little closer look at the wealth of credible information (published by WHO, etc.) concerning Vitamin D deficiency, however and you will come away with a more informed outlook. What you find are some astounding statistics staring aggressively back at you. Estimates indicate that upwards of 50% of the world’s population suffers from VitD deficiency to some extent or other.

Although a few hours out in the noonday sun can supply a whopping 10,000–25,000 IU of VitD (and this form is likely to be more easily processed by and remain in your body for a longer period of time than any oral version currently available), there exists all manner of confounding factors that have the potential to hinder or otherwise interfere with the physiological and biochemical processes leading to the manufacture of your own private supply of this very important vitamin.

Here’s a shortlist of some of these confounding factors: age, kidney or liver conditions, genetics (possessing the right VDR alleles will be helpful), race and skin type (darker skinned people need more sunlight to manufacture the same amount of vitamin D3 than lighter skinned individuals), sunscreens (oh yes, they do keep you from getting sun damage and skin cancer, but at a price) and certain medical conditions, including AIDs. Seems a lot of things out there in the real world can create processing headaches for you and get in the way of all those freebies.

Here's another shortlist, this time of what comes with not getting the required dose of VitD:

Fatigue
General muscle pain and weakness
Muscle cramps
Joint pain
Chronic pain
Weight gain
High blood pressure
Restless sleep
Poor concentration
Headaches
Bladder problems
muscle wastage
Lack of growth
Hmm you say to yourself, kind of scary.

Surprisingly, Mama Nature herself provides few good food sources of VitD. Mushrooms are pretty decent sources of VitD2 (there are 5 versions of VitD) and, of course there are the unnaturally fortified dairy products, if you happen to be a milk drinker and don't mind the lactose.

Unless you are often found out in the backyard happily gathering tasty but awfully hard-to-find truffles, surfing a few sets of bodacious shapes out at Pt. Magu and/or swigging down litres of fortified milk products throughout the year, you might consider supplementation to be advantageous.

Think of it as a cheap form of insurance.

It's going to be difficult for me to give much positive input on this book. I disliked it in several different ways on a few different levels.

Personally, I find 1* ratings often much less useful than 2* or 3* ratings. Usually because the reviewer issuing them often has a bias that I can't share or empathise with. But here a 1* rating seems to me mandatory, unusual because so many other reviewers seem to have a high opinion of this book. It consistently receives high ratings on both Amazon and GoodReads.

The author is a Holistic Practitioner and I have nothing against Holistic Medicine, as long as the techniques available work as well or better than a placebo (the same requirement that I have for mainstream medicine). I have found some some techniques such as acupuncture and massage very useful.

Don't misunderstand me, the author gives some astute and sound nutritional advice. But this advice could similarly been dispensed in a more straightforward and less pseudo-scientific manner than that found in this book.. A simpler, less dogmatic treatment treatment might have generated more trust, less scepticism than the sort of totalitarian-health-utopia protocol that DIRTY GENES promotes.

The secret of a good con artist, a professional classification that most self-styled experts, snake-oil salesmen and gurus tend to fall into, is that much of what he says will seem to ring true. A good con will take off and really sprout wings once the practitioner has gotten his mark to trust him enough to cause a suspension of disbelief. If you look and talk the part of an expert, then you take on much the same opinion of the emperor's new clothes as the emperor himself has of his own costume.

As my 12 year old daughter once plainly scolded me years ago (with obvious mixed feelings): "Dad, stop pretending. If people want to believe in Santa Clause, we should let them because it's nice to believe in him. But that doesn't make him true."

Somewhere at the beginning of DIRTY GENES, the author offers the advice that it's not necessary to test for the genes that he is covering, for expediency's sake, you can just follow his checklist to determine whether or not you possess them. He comes up with the simplistic concept of a "dirty gene", one which can be scrubbed and cleaned up using his protocol. This obvious attempt at marketing his point of view by dumbing down the rather complex subjects of genetics, epigenetics and nutrigenomics possibly makes sense as far as making it more comprehensible to a standard 12 year old reader is concerned. He is merely being dogmatic, creating a false sense of utility and further obscuring the whole fascinating and powerful topic by doing this for the rest of us.

Far from empowering his readers and providing them the buoyant hope that he/she has the ability to fix his or her less than optimal DNA strands (should he or she find them annoying or bothersome), he employs a rather transparent set of psychological tricks compounded with the latest scientific sounding catchword phrases to create an alternative reality that sounds and seems intuitively plausible, without the advantage of being rock-solid or scientifically proven.

In my opinion, it just doesn't work. Not because it isn't possible, as I think that the subject itself has fantastic potential to improve the lot of most living creatures on this planet. The concept inherent in DIRTY GENES doesn't work simply in the same way that the emperor's nice new suit of clothes didn't.