Deservedly, these scientific advances received front-page coverage in newspapers all over the world. And yet one discovery, buried deep in the pages of the august British Medical Journal (18/25 December, 1993), went virtually unnoticed. I refer, of course, to that landmark study: “Is Friday the 13th bad for your health?” Written by four British researchers, the paper finally confirmed what most of us have long suspected, namely that Friday the 13th really is dangerous to our health. They pointed out that not only is 13 widely considered an unlucky number, but also that in some parts of Britain to call a doctor for the first time on a Friday – though not necessarily the 13th – is a certain omen of death for the patient.

Tom Scanlon and his colleagues from the West Sussex Department of Public Health, Haywards Heath, compared the driving and shopping patterns of those brave or foolhardy enough to venture out on Friday the 13th to those going out on Friday the 6th. They also counted the number of accidents on Friday the 13th and compared them with those on Friday the 6th. What they discovered was that there were significantly fewer vehicles on a section of the M25 on Friday the 13th than on the previous Friday. This suggested that some people are sufficiently superstitious to temporarily change their daily routine and refrain from driving on Friday the 13th. But if people were not driving, what were they doing? They were going in droves to supermarkets, many more on the 13th than on the 6th. But is this really so surprising? Not in the least. When I am nervous, and I suspect I am not alone, I eat twice or three times as much as I do when I am at peace with the world. So the nervous strain of having to live through the fateful day thinking about all the awful things that might happen to them likely gave many people an enormous appetite. They had to satisfy that nervous hunger by stocking up and consuming increased amounts of food. But how did these nervous shoppers get to the supermarkets if there was less traffic on the 13th?

Knowing instinctively that their odds of having a major fender bender were much greater on the 13th, the shoppers went to stores relatively easy to reach by foot or public transport. Or was this just a statistical aberration, as scientists like to put it, when they cannot explain something? Perhaps the normal complement of shoppers was supplemented by inhabitants from a nearby galaxy, disguised as Homo sapiens, who only visit our planet on the unhealthy 13th to make mischief.

The number of motorists who wound up in hospitals as a result of major fender benders was significantly greater on the unlucky 13th. In fact, drivers who ventured out on the road on that day had a 52 per cent greater chance of ending up in hospital than those who were on the road the previous Friday. To no one’s surprise, the authors concluded that Friday the 13th was unlucky for some. Their recommendation? Stay at home on that day.

Last year, thank God, there was only one Friday the 13th. But this year we are not so lucky. There are two. I have already lived through one without a major mishap. Since I do not feel like tempting fate any more often than I have to, the safest course for me to follow from now on is to stay in bed all day on the unlucky 13th.

I intend to do this because although Scanlon did not study the possibility, I suspect that many more accidents also occur in the home on the 13th than on any other day of the year. For example, I can envision stumbling or falling out of bed, especially if it is the wrong side, and most likely fracturing a bone. Of course I would want to call a doctor. But I would not dare to. Calling one for the first time on any Friday, never mind whether it is also the 13th, could be a sure omen of death. Still, I need not worry on that score. Where I live, finding a doctor who makes house calls, even in the direst emergency, is about as likely as finding a gold sovereign on the ground.

Would I be better tootling along country roads on the 13th instead of lolling in bed all day and coming down with a chronic case of inertia for the rest of the weekend? Perhaps. Scanlon and his team also found there were more hospital admissions on the 13th – including poisonings, so I must make sure not to antagonise my wife during the week before the fateful Friday. Otherwise she might just be tempted to add some weedkiller to the sugar jar from which I always add three heaped teaspoons to my morning cup of coffee.

As a cell biologist, I am always a bit sceptical when I read of breakthroughs in the scientific literature. Scanlon’s data, analysed by sophisticated statistics, are impressive. Yet not until other researchers in Molepolole (Botswana), Bitely (Michigan), and Jinst (Mongolia), have confirmed his results will I venture a resounding “Yes!” to the question he and his group pose at the beginning of their article.

Still, from now on to be safe, I shall follow their advice and stay home on the fateful day. And I will not budge from my bed. After all, a mere 24 hours of sloth once or twice a year cannot do me any harm. I shall recommend this course of action to all my friends who may be as nervous as I am when the unlucky day approaches.

The titles fall into three categories: sex, food and miscellany. Take
sex. A paper appeared in Trends in Biochemical Sciences that asked ‘What
turns platelets on?’. Platelets are those tiny cell fragments in our blood
that prevent us from bleeding to death every time we cut ourselves. They
do this by swarming to a tear in the blood vessel and plugging it, like
thousands of Dutch boys sticking their fingers into a leaking dyke.

Under the microscope, platelets look like a bunch of fleas. So I was
intrigued that anything that small could have a libido. Imagine my disappointment
when ‘What turns platelets on?’ turned out to have nothing to do with sex.
Instead the authors told me much more than I wanted to know about what starts
these creatures charging to the rescue when I’ve sliced off part of my thumb.

The mating game among moorhens seems to be of such great interest that
the journal Science published a study showing that ‘Female moorhens compete
for small fat males.’ It seems young female moorhens fight other female
moorhens by jumping into the air and hitting their opponents with sharply
clawed feet. And why do they fight so fiercely? Because they are competing
for fat ‘high-quality’ male moorhens, which instead of flying to the office
every day, stay at home in their nests to take care of the kids.

In the miscellany category, my colleagues have written learned papers
on ‘The problem of problems’, ‘Peppy esters’, ‘Birds that ‘Cry Wolf’ ‘.
They have also tried to answer the question ‘Are biological structures piles
of molecules or just heaps?’.

But it is in the pages of the British journal Nature-a pillar of the
scientific establishment and the journal in which the structure of DNA was
first published-that some of the most challenging articles for both researchers
and lay readers have appeared. If you are a nervous eater who counts each
grain of salt you sprinkle on French fries, then you should read ‘Salting
of food: a function of hole size and location of shakers’, the now-famous
paper that Nature published a few years ago. What this short paper tells
us in four very long paragraphs is that the bigger the holes in the shaker
and the closer you’re sitting to it, the more salt you are going to sprinkle
on those French fries.

Biologists take pride in being objective; they avoid dealing in personalities.
But Nature broke that rule when it published a paper by three psychologists
who wondered, ‘Why is Mrs Thatcher interrupted so often?’ Yes, the Mrs Thatcher.
The authors were probably skipping through the TV channels when they chanced
on Denis Tuohy’s programme TV Eye.

Tuohy, who does a talk show in Britain, was interviewing the former
prime minister. For example, whenever Thatcher got into her verbal stride
by enlightening the audience about how she went about spring-cleaning at
No 10, Tuohy interrupted her. Using some sophisticated audio apparatus,
the authors discovered that Thatcher was ‘unconsciously displaying turn-yielding
cues at inappropriate points . . . ‘ In other words, Tuohy thought she had
finished speaking since she gave him certain hints or ‘turn-yielding cues’
(‘whispery voice’, ‘creaky voice’). But of course she was far from finished
with the subject of spring-cleaning.

Some of the more interesting titles deal with food. The British Medical
Journal recently published a paper on ‘Rhythmic raiding of refrigerator
related to rapid eye movement sleep’. The subject of this short report was
a man who was concerned about raiding his refrigerator to eat and drink
three to five times each night, or about once every hour and a half. When
he was studied by two psychiatrists in a sleep laboratory, he put next to
his bed two bottles of soda, a pork pie, several packets of potato crisps
and a packet of biscuits. The authors reported that this nocturnal eater
was briefly awake when he started eating and drinking, but that he would
fall asleep while chewing his food.

Rats and mice are now the biologists’ favourite animals. So it is only
to be expected that as our own lifestyle has improved, that of laboratory
rodents should have improved also. Most laboratory rats and mice are fed
small, dark-green rectangular biscuits, the so-called ‘laboratory chow’,
which have the consistency of chocolate-chip cookies but lack the chocolate
chips. Now some researchers are feeding their animals yogurt (‘Influence
of a diet additioned with yogurt on the mouse immune system’), tapioca and
rice (‘Effect of feeding cooked tapioca as compared to rice on the metabolism
of glycosaminoglycans in rats’), and even sake, the Japanese rice wine (‘Accumulation
of hepatic collagen following long-term administration of sake to rats’).

Some rats are so well treated that they are fed ‘cafeteria style’. Two
papers-‘Effect of high protein cafeteria feeding on serum cholesterol and
atherogenesis in the corpulent rat’ and ‘Increased alpha-l-adrenergic receptor
density in brown adipose tissue of cafeteria-fed rats’-made me wonder whether
rat cafeterias bear any resemblance to the old Horn & Hardart cafeterias
in New York where 50 years ago a three-course meal cost less than a dollar.

We are told the cafeteria-fed rats were offered unlimited amounts of
‘a high animal-protein cafeteria diet prepared fresh daily and consisting
mainly of cooked eggs (scrambled and fried, omelettes), red meat (roast
beef, baked ham, bacon, sausage patties), and assorted cheeses for eight
weeks’. No after-dinner brandy or cigars, though. But these rats had no
cause to complain since their control cagemates were fed only the dull laboratory
chow.

As the researchers soon discovered, the rats that gorged themselves
lost their trim figures and their arteries eventually hardened to the consistency
of lead pipes. Still, they must have found it difficult to get back to the
old diet of hard biscuits when the experiment was finished. What I’d like
to know-the authors forgot to mention this in their paper-is how many of
the rats who chose fried eggs ordered them easy over instead of sunny-side
up.

Frank Ulrich is a cell biologist and associate professor in the department
of surgery at the Tufts University School of Medicine in Medford, Massachusetts.