Brought to you by the letter U


The u- or j-shaped curve is a feature of a lot of research studies on health-related topics. “Moderation in all things,” is as true now as it was when Hesiod and/or Aristotle doled out the advice thousands of years ago. It’s also a key to some of the trickiness of health advice – you can get too little or too much of a thing. People like to latch onto particular foods or behaviors as being healthy or unhealthy, but none of them exists in isolation. I mean, sure, kale is packed with all kinds of minerals, but if you only eat kale, the results aren’t going to be pretty.

Here’s another maxim from the ancients: “The dose makes the poison,” attributed to Paracelus, a Swiss alchemist (b. 1494-ish, d. 1541). That can apply to everything from Tylenol to red wine, both of which will, in sufficient quantities, utterly destroy your liver, but which are pretty okay in small doses. Fish, likewise, is good for you (Omega 3 fatty acids are important), but because it also often contains some heavy metals (not so good for you) you should go easy on it. Then there’s exercise. None is very bad, and any amount more is better, until you start to get to the point where you’re utterly wearing yourself out.

One of the first places I ran across this relationship was when I was wondering about optimal weight. According to the stock advice these days, normal weight is defined by the 18.5 to 24.9 range of BMI (Body Mass Index, more on this in another post). However, “Normal” does not match the range of the BMIs with the lowest all-cause mortality. “… many epidemiological studies show an inverse relationship between mortality and BMI inside the normal BMI range. Other studies show that the lowest mortality in the entire range of BMI is obtained in the overweight range (25–29.9).” This paper has a long title: “How Much Should We Weigh for a Long and Healthy Life Span? The Need to Reconcile Caloric Restriction versus Longevity with Body Mass Index versus Mortality Data.” It also has a nice little chart which shows lowest mortality at a BMI of 23.4, but no significant difference from 20.8 to 27.7. 

The u- or j-shaped curve also shows up when you look at the results of exercise, eating red meat or protein, drinking alcohol, or eating sugar, though in those later two cases it’s unclear that any amount is really good for people. Sleep is another problematic example, which merits a blog post of its own. 

For almost everything, there’s going to be a balance. Fortunately, we’re adaptable creatures, and that balance point is very broad without a gigantic drop-off for most things. Don’t get too stressed out if you’re not hitting the bullseye. Being more or less on target really is good enough. Still, it helps to have some idea of what the targets are, and that's what I'll get into in a little while. 

Comments

Post a Comment

Popular posts from this blog

Creating a Home for Body, Soul, and Spirit by Bernadette Raichle rating: 4 of 5 stars I borrowed this book from the local Steiner playgroup. I've enjoyed the parent-toddler group, and have picked up a lot of ideas about education and childrearing from its Steiner/Waldorf based activities, but I've always been a bit uneasy about its philosophical underpinnings. Here, at last, was a book which was explicit about how Anthroposophy informs the operation of a daycare centre, and man, is there some whacky stuff in there! The anthroposophical jargon about creating a "penetrated" environment and the four sheafs (Physical, Etheric, Soul/Astral, and Ego) would turn off most people I know, but it does explain why Waldorf kindergartens are organized the way they are. I gave this book four stars because it was exactly what I was looking for, and because I think it is useful, but it is not particularly well-written. Some sections are less well-developed than others, and as I
Read more

Spanische Windtorte

Image
When I was young, my mother had a nearly-complete set of the Time-Life Foods of the World cookbooks. Although the recipes in these were not, as a rule, very good, I was much taken with the photo on the cover of The Cooking of Vienna's Empire -- a Spanish Windtorte. I told my mother that I wanted one for my birthday cake. I had not grasped quite how difficult they were to build. I think we wound up with more of a Pavlova instead. The thing is, a Spanische Windtorte is almost exactly the same thing as a pavlova, only with a fancier-shaped meringue. So, when I set out to make one again yesterday, I used a combination of this Pavlova recipe and these Spanische Windtorte instructions . I increased the quantities in the pavlova recipe by about 1/3, and, in the final step, did not macerate the fruit but rather mixed it with sugar immediately before adding it to the whipped cream mixture... but I'm getting ahead of myself. Making the meringue was fairly straightforward, except that
Read more

Transatlantic Baby

Nova is about to embark on her fourth transatlantic flight since she got out of the womb.  I wish we didn't have to go back and forth so much, but that's just how it's turned out. The first flight was on New Year's Eve, when she was just over a month old.  She surprised me by sleeping almost the whole way from Newark airport to her grandmother's house in Galway.  On the next two flights, I traveled alone with her, and honestly it wasn't so bad.  The flight attendants on Continental pretty much ignored us, and offered me no extra help.  Aer Lingus was a different story, with the flight attendants all offering to hold her and walk up and down the aisles, or sit with her if I needed to go to the toilet.   Each time, I've brought a little less with us.  This time Nova's equipment will consist of a stack of disposable diapers, a small towel, a blanket, a change of clothes, some cotton wool, a teething ring, baby tylenol and bum ointment just in case, maybe a
Read more