Welcome to the fat years
Of the self-inflicted problems in the world, religious strife is probably the worst.
A close contender, however, is obesity, which is going to cripple the world's health systems with costs to treat diabetes, heart issues and other obesity-related problems.
As we keep hearing, it's a major problem in New Zealand but it's really come home to me since I've been in England where main streets or public transport bring you into contact with so many more people than back in Christchurch.
Obese people and beer guts are much in evidence. I always come home determined to cut down on calories.
The health costs are enormous. The National Health Service spends about 10 per cent of hospital costs on treating diabetes and its complications. New Zealand is probably close.
I used to scorn fat people in way that only a skinny person can.
Up to the age of 40 I could eat what I liked and I used to exercise a bit too.
The exercise regime suffered with children, house maintenance and a less self-centred life.
By my late 40s I was still in reasonable shape except for being a bit overweight, with most of this excess poundage around my waist. This, surprisingly, was caused by eating too much.
I lost my disdain for fat people. I had reached the stage where I couldn't maintain a healthy weight by eating what I wanted. I had joined the millions with the First World problem of being unable to resist food.
Like most men my age, my trouser size went up a couple of sizes and the belt went out to its last adjustment.
I didn't consider myself unhealthy and I didn't run out of breath if I took the stairs. That basis level of fitness that I had relied on for 50 years would see me through, I reasoned. I didn't try dieting or any of that shemozzle.
To me the whole dieting industry can be reduced to one very simple rule. Eat only tiny amounts of crap food, don't eat too much good food and get some exercise.
The exercise I was getting early in my second century was not shifting any weight unfortunately. I was still eating too much and I was getting gradually heavier.
This was not good for someone from a family with both diabetes and heart disease in the genes.
By the time I was 54, I really needed to lose a few kilos.
Then all of a sudden, almost in a couple of weeks, I lost 3kg. Brilliant, I thought. As it turned out, I had bowel cancer.
After an emergency operation, I lost 7kg. At least one benefit of having cancer, I thought.
Within a few weeks of the operation I was my old ravenous self again and the weight went up.
It took me about a year to get over the various operations and chemotherapy before I started feeling normal again. A good friend got me out walking regularly and within a couple of months I was running, not with the old energy but at least running.
Then in February I started feeling tired and unwell again. In about three weeks I lost 7kg. I was a good weight but I looked, as people who lose weight often do, terrible.
I thought the cancer had come back but it was only an over-active thyroid which could be treated. I started on medication and the weight loss stopped and I started to pile it back on.
Then I went to Cambridge for a 10-week fellowship.
I thought I should try to get a bit fitter. One day I thought I would see how many press-ups I could do. I could do one. The next day I could not do any.
I was shocked. Sure I could run a bit but how did I get so weak?
I persuaded my fellow Kiwi fellow, Mike White of North and South fame, who is a natural athlete and many years younger, to alternate our running days with a bit of gym work.
We both hated the gym work but I gradually got a bit stronger and felt better for it.
The moral of this little tale is an old one but bears repeating. You will get heavier, weaker and less fit with age but it should be a very gradual decline. I suspect your 50s are very important because they set you up for your more vulnerable 60s.
So here is the moral. Get off your arse, do some strength as well as aerobic exercise and don't eat so much. But you don't need me to tell you that.