What I've Learned

Cons

• Possible headaches - remember, drink very large quantities of water. 
  Moseley states that you should "urinate 6-7 times per day" as a result of your water consumption.  I found that if I didn't drink to that quantity, headaches were likely - and that I saw the skin of my fingers start wrinkling and I would use that as a cue to drink more.  I took to drinking sparkling water - it's become an expense!
• Mild mental effects - probably due to ketosis.
  If you check "Adverse effects" there you'll see there aren't many.  Specifically, what I've found is some sense of dizzyness - or something like it - but without an actual loss of coordination or balance.  And again a sense of confusion - without actually losing my train of thought or misunderstanding anything (I've been able to work effectively throughout).  Occasionally I've felt light-headed after getting up quickly - low blood sugar?
  Overall, these "negative" effects are less influential on state-of-mind than, say, coffee.
• Constipation - even with plenty of fibre!
  My theory is that my digestive system removes practically all energetic material from my food and that digestive bacteria levels have dropped to a relatively much lower level so that there's just much less need for defecation.  But I'm not an expert.  What I find is that I go to the toilet (for no. 2) much less often - every few days.  This is somewhat concerning, but not a major problem so far.  Definitely eat plenty of fibre.
• Gas - but only after going to 700.
  Strangely, while at 800 kcal/day this problem (er... flatulence) did not occur.  While otherwise the effect of changing from 800 to 700 kcal/day was not massive - this was a noticable effect!  I don't have an explanation.
• Lower physical pace - possibly.
  It seems to be the case that I'm somewhat less active.  I'm aware that in fact there is an effect, for instance that when you choose to exercise more you tend to instinctively rest more to compensate.  Something similar may happen with the Very Fast level of dieting - that would be logical.  But, for instance, if the effect is real it is not restricting - I still complete all my necessary tasks, like shopping, garbage disposal, going for morning coffee and so on.
• Hunger - in a social sense, not physically.
  I don't feel actual debilitating hunger - as I explain here.  I believe this is due to the low-carbohydrate aspect of the diet.  I don't suffer in that sense.  However, now, towards the end of the diet, the social or cultural effect is being quite keenly felt.
  The process has been very interesting and illuminating about how humans interact in modern society.  I realise that I value this interaction.  I look forward to the end of the diet to re-engage.  I hope I'll retain my new understanding of my culture and participate more consciously in it in future.
• Difficulty participating socially - coffee and water.
  I do (now, toward the end) rather look forward to being able to participate in society properly!  It's dragging on...  I am now day-dreaming occasionally - even actually dreaming - of eating rich prepared foods.  This is not hunger though.
  I have been "out" a couple of times.  On one occasion I just had coffee and water - no-one minds.  It is possible to participate with friends at restaurants by adjusting diet meal-times, choosing dishes carefully and estimating amounts (my wife forbid me from taking a scale to restaurants).  Also, there should be no real problem in accepting that sometimes total caloric intake may go beyond the levels chosen very occasionally.
  For me, personally, I have avoid this mostly.  It happened (I think) on a couple of occasions.  My response was to estimate how many calories I went over and then "penalise" myself to that level the next day.  I expect this was unncessary, but it helped with my sense of discipline.
  Overall, with "going out" I find that most friends and family are highly supportive and don't push me to eat more heartily.
• No alcohol - it doesn't add up.
  I am a drinker - sometimes too much.  On this diet though, given that a single would be about 1/3 of a day's energy intake, it has never seemed reasonable.  Perhaps, at the end of the diet I'll try it and see how it feels.  But, given I'm dieting, generally speaking, to improve my health, having time without alcohol works with that.  I've hardly missed it.  I'm looking forward to a beer in celebration when I reach my weight target - but not desparately.
  

Pros

• Weight loss - dramatic.
  If you do what I've done, which is to buy an accurate scale and then use either the dietary labels of calorie levels per 100g on packages or else look up via Google the calorie levels for unpackaged foods, and never let anything else pass your lips (other than pure water) and eat no more than 800 kcal/day, you're guaranteed to lose much weight fast.
  I've lost more than 25Kg so far - I'll keep going until I've lost 31Kg (108Kg down to 77Kg).  This is a life change.  It will improve my health dramatically.  It's a triumph.
• Understanding of eating - a new relationship with food.
  As I explained, I've gained an appreciation of the actual reasons I would eat.  Almost never from hunger!  We are unique as a species to not be motivated by the avoidance of hunger.  Eating has become a distraction, a way to participate in our culture, an addiction - but it's not about sustenance.
  This has been eye-openning and I value this greatly.  I treasure the new appreciation I have of food.  I'll expand on this in the next point.
• Mindful eating - now I get it.
  My wife introduced me to mindfulness many years ago after she started meditation.  I found the concept compelling and over time it has become a great tool in many ways in my life.  I discovered the concept of mindful eating in that time too - but didn't find it very important or applicable to my life.  I thought "I don't have time for it".  This diet has changed that conception.  Now - to some large extent because my meals are smaller and less frequent, I eat more slowly, more deliberately and appreciate the variations and combinations of taste.  This is interesting and enjoyable.  I very much hope that I continue with this relationship with food and eating henceforth.  The sense of taste is to be valued.  Food can be, and - even with everyday foods - usually is, beautiful.  I'm looking forward to going to good restaurants to appreciate in a way that perhaps I never really had before, the art of food preparation.  This is really a wonderful change that I didn't expect as the result of this diet.
• Positivity - my mood is improved.
  Moseley suggest that as a physical effect of reduced caloric intake there - paradoxically - an increase in sense of well-being.  Hemmingway and others have said the same thing.  I have felt this, though, why it is I'm not sure.  It might be the good feeling of first embarking on the diet and then quite immediately seeing its success (just in the first days - and then continuing).  But overall I feel emotionally better, even now after many weeks.
• Greater compassion - I better see the values in life.
  This is a strange one.  Perhaps it is a result of the positivity.  Perhaps an effect of ketosis.  I find myself more interested in aesthetics and this includes that of other humans.  I'm interested in understanding them, and as such, necessarily there is forgiveness.  This is compassion I think.
• Life change - this is for good.
  It seems to me that I now have the tools to keep my weight under control at a healthy level.  I have a way to keep track of my energy intake that I have tested and know I can execute when I need to.  I know that, if my weight increases, I can decrease it without a significant cost, otherwise, to my lifestyle.
  On-going, I can return, basically, to my previous lifestyle, so long as I keep track of my weight and re-adjust it occasionally if necessary.  On the basis of this calorie calculator for example, to maintain my target weight (with little exercise) I would consume 2258 kcal/day.  At my original weight it would be 2685 kcal/day.  Given that I was gaining weight slowly before the diet, perhaps I was eating 2800 kcal/day or so.  The difference is not huge proportionally.  I will be able to eat similar quanties of similar foods as before.  Initially I will keep some track of energy intake and food type etc - and be more mindful anyway.  I do not want to return to obesity - ever.  I will continue with this blog, from time to time, with updates.

Differences

With weight loss of this scale coming so rapidly - you notice it - at least in some ways.

• Bones - can feel them.
  I can now easily feel every accessible bone in my body I think.  I was thinking this is suggests I'm becoming skeletal - but my bodyweight is still on the high end of normal range.  Basically this is normal.  Nevertheless it's rather strange for me to feel my shoulder-blades and ribs when I wash.
• Joints - feel different.
  I feel as though my body is somehow "looser" as if my joints are not as tightly held together.  My knees feel slightly wobbly and shoulders and elbows seem to have more "play" in them.  I suppose it might just be the case - with thinner fat layers around them.  I haven't done any research on it - not sure.  Or, perhaps just being significantly lighter, there's less tension on these parts of my body and that's what I'm feeling.  It's not a bad feeling particularly, just slightly odd.
• Calmness - something like serenity.
  I have a feeling this is a ketosis effect.  Probably it is an evolutionary mechanism of reducing activity when in a near starvation period.  In fact this slows down my weight loss rate and I need to combat it - which is difficult, since it is not a bad feeling.
• Face - looks different.
  It's possible some people won't recognise me since the loss of fat on my face has changed its shape significantly.  Some might suspect I'm ill.  My cheekbones are now prominent.  My neck has some "turkey" features.
• Body - changed silhouette.
  I'm much thinner - very much noticeably.  What is there to say - "I've changed" - I've actually changed - physically (and mentally/psychologically).  It's a pretty big deal!