The debate: Rickets or child abuse?
Is a new global epidemic of rickets being confused with mistaken findings of child abuse?
Humans need sunshine to make Vitamin D to make bones.
If you're pregnant, white and you cloak your skin with sun-block in New Zealand, you may end up giving your baby rickets - an age-old disease which leads to weak and easily fractured bones. And those symptoms are seen as a serious danger sign for possible child abuse.
Equally, if you're pregnant, Thai and live in dark-for-half-the-year Sweden, you are in danger of not getting enough sun - and that also means your babies could end up with rickets.
The problem is that rickets and child abuse share some of the same symptoms - so which is it?
That's not an academic question for Erik Eriksson from Sweden, who faces four years in prison because he has been held to have violently shaken his 16-day-old daughter, Linnea.
His Thai partner, Nancy, stands by him. There is no other evidence that he is a child abuser.
Lock him up and throw away the key - you might be tempted to say.
Erik is in dire trouble because his daughter had multiple fractures and bleeds over the brain. And, many experts say, they must have been caused by someone. But that is not a fact.
It's a deduction based on a controversial theory called Shaken Baby Syndrome - see my previous blogs on the Keran Henderson case. Keran is serving a sentence for manslaughter but she denies shaking the child in her care.
And many people who know her believe her.
In Erik's case, there is another explanation for his daughter's condition, one for which there is evidence, in New Zealand, the United States and many other countries, and that places a big question mark against the 'certainty' of Erik's guilt.
The other theory argues that Linnea's fractures were caused by congenital rickets because her mother, Nancy, is originally from Thailand and the combination of the dark pigmentation of her skin and the weak sunshine in the far north of Europe caused Vitamin D deficiency and that caused weak bone growth in the womb and that caused Linnea's fractures.
But what about the bleeds over the brain? Well, there is evidence that they can happen naturally in child birth and it is very hard to date them precisely. So, not abuse, necessarily..
Dr Kathy Keller and Professor Patrick Barnes at Stanford University have written a paper - 'Rickets vs. abuse: a national and international epidemic' - that sets out the evidence that Vitamin D deficiency is getting worse in the United States and it gets worse in winter.
Black, white and everybody in between are suffering from more cases - while the Vitamin D in food and milk is lower than it has been for a generation.
From this study, it looks like lack of sunshine in northern climes and worries about skin cancer, particularly in white people, have caused a new and silent problem: childhood rickets.
In New Zealand, Annie Judkins and Carl Eagleton, got worried when they found ten cases of childhood rickets in three years in one GP's practice in Wellington.
They tested 90 pregnant mums for rickets and found that almost nine out of 10 were Vitamin D deficient - and some two thirds had a serious deficiency.
The mums were from a wide spectrum: African, Maori, European, Middle Eastern, and Polynesian.
Shaken Baby Syndrome has powerful defenders in the child protection community, who argue that it is valid science and that perpetrators have confessed to it.
However, it is also the case that no-one independent has ever witnessed a shaking leading to the symptoms - bleeds over the surface of the brain and in the eyes and brain damage - alleged to be found in the syndrome and no-one has ever filmed it.
Erik faces the legal hurdle that his defence relies on new science - rickets plus child birth - and judges like old precedents - SBS.
This is a problem that one of his defence experts, Dr Waney Squier, is familiar with.
The Oxford neuro-pathologist helped clear Suzanne Holdsworth of the false finding of child murder of Kyle Fisher - see my previous blog. (The Independent Police Complaints Commission are now investigating the integrity of the first Cleveland Police investigation into Holdsworth's conviction.)
Dr Squier, a sceptic on Shaken Baby Syndrome, argues that Baby Linnea had just been born - and that if you combine congenital rickets with a difficult birth, then bleeds in the eye and over the surface of the brain are natural events, not child abuse.
The Swedish judges have thus far dismissed the evidence from around the world that suggests that Erik might never have harmed his little girl at all. The matter now goes to final appeal.
The problem is that if Eric is innocent but goes to prison because of questionable science, then it is likely that many more children in Sweden and elsewhere, including Britain, will suffer from rickets - a wholly preventable disease - while the food and milk manufacturers are under no pressure to boost the level of Vitamin D.