bearing blog

" I'd call for all the chemists who've ever worked with a hexanitro compound to raise their hands, but that might be assuming too much about the limb-to-chemist ratio."

Organic chemist Derek Lowe has another edition of "Things I Won't Work With." 

This post includes a description of how the organic chemist goes about deciphering compound names, which makes it worth a look if you like language.  He also gets in a reference to Verdi opera, incidentally.

I hope he writes a book called "Things I Won't Work With" someday... I would pre-order it NOW.

Low-carb, low-impact.

Mark sent me a .pdf of a very interesting paper the other day:  "Nitrogen and Food Production:  Proteins for Human Diets," V. Smil,  Ambio vol 31 no 2, March 2002. It got me thinking about lower-carb living and sustainability.  

One way to think about farming:  "[A]griculture's principal objective is the production of digestible [nitrogen]."  Nitrogen is a proxy for protein, and its availability in the soil limits how much protein can be produced from the land.  That's why the advent of ammonia fertilizer led to such an explosion in land productivity.  But nitrogen fertilizers have environmental costs, and so we want to use them efficiently. 

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Back when I was trying to live low-carb, Atkins-style, one of the things that troubled me about it was that it seemed so... gratuitously meaty.    The Atkins folks are now recommending "at least 4 to 6 ounces of protein foods per meal," "8 ounces... if you're a tall guy," but five or six years ago I had gotten the distinct impression that you were supposed to eat "as much as you want" of bacon and beef and the like.  

Basically, the impression was:  Replace your bread, rice, and pasta with meat, eggs, and cheese.  Right?   And of course, even now, six ounces of protein-based foods per meal is more than a pound a day.   You've got to eat something, right?  And you don't want to be hungry?  And carbs are out?  So high-protein must be in.

But of course this is far more protein than individuals need.  Protein can't be stored,* so eating extra is wasted.   It's greedy, too, on a societal and environmental level; Americans overeat it, and pour nitrogen fertilizers into the soil in order to overproduce it, while in other parts of the world demand outstrips supply.

So why is the Atkins recommendation so high?  I think it's because the Atkins diet sells itself with that "you can eat as much as you want" theory.  The extra meat will fill your plate and your stomach, be satisfying to chew, and taste good; it is made of "normal" stuff that you're used to eating; and if the research on insulin resistance is to be believed, it won't contribute to your fatness.  You can, indeed, lose weight while eating lots of Atkins hamburger salads.

But it's still wasteful, if you're eating more protein than your body needs.  And the more people in affluent nations who try to fix their fatness by following Atkins-style high-meat low-carb, the more overall global demand for meat rises -- and for already-overnourished nations like us, that's shameful.

* * *

This is one reason why, even if we concede that high-refined-carb diets cause obesity and low-carb diets can cure it, we still have a gluttony problem.  A pound and a half of meat every day is a ridiculous amount of meat to eat, even for a "tall guy."  

Let's concede that a small number of obese, insulin-resistant people will not respond to a diet unless it contains virtually no carbohydrates at all.  These few folks will need a diet that's almost all protein and fat, of necessity based mostly on animal products.  They want to eat reasonably-sized meals with enough calories in them that they don't suffer terribly.  Okay, let those few people subsist on mostly meat, and more meat than their protein requirements call for.   Chalk it up as an expensive medical treatment.  But it's terribly wasteful to start there as a first resort for weight loss, or worse, for a lifelong way of eating.

* * *

Here are some things to keep in mind when designing a lower-carb, but more-sustainable way of eating.

1.  Too much protein and too little fat is an important cause of the famous constellation of side effects that accompany "Atkins-style" low-carb eating.

From Gary Taubes, Why We Get Fat, pg 214-216:

This shift [from running on carbohydrates to running on fat] can come with side effects.  These can include weakness, fatigue, nausea, dehydration, diarrhea, constipation, [postural hypotension], and the exacerbation of pre-existing gout.  ... This reaction is why some who try carbohydrate restriction give it up quickly. 

...The reason for the side effects now appears to be clear, and physicians who prescribe carbohydrate restriction say they can be treated and prevented.  These symptoms have nothing to do with the high fat content of the diet.  Rather, they appear to be a consequence of either eating too much protein and too little fat, of attempting strenuous exercise without taking the time to adapt to the diet, or... a web of compensatory responses [from the beneficial drop in insulin levels] that can lead to water retention and what are called electrolyte imbalances.

So too much protein is one cause of the unpleasant side effects.  Eat more fat and less protein -- which means you can eat less animal product and more vegetable oils like coconut, avocado, olive -- and the lower-carb adventure might feel a whole lot better.  (Meanwhile, make sure you get enough salt and don't overdo the exercise).

 2.  Don't overestimate your daily protein requirements.  Three grams for every ten pounds of body weight is slightly more than you probably need -- a number I get from using the recommendation of (0.6 g protein)/(kg body weight)*.  Another way to think about it is one gram per ten pounds of body weight at each of your three meals.  

I weigh 113, so it's doubtful I really  need more than 34 grams of protein per day.  Let's be generous and call it 36:  12 grams of protein at each of breakfast, lunch, and dinner.  So at each meal I can get enough protein from:

• 2 eggs; or
• 0ne-third of a small (5 oz) can of tuna; or
• one smallish chicken thigh; or 
• less than 3 ounces of not-particularly-lean ground beef; or
• almost two ounces of cheddar cheese; or
• a cup and a half of whole milk or yogurt.

Now, if I got most of my protein from plant sources like beans and grains, I might need to eat more, because the body uses the protein in these less efficiently.  And mind you, I don't weigh very much.  If you weigh 250 pounds, you might need twice what I need.  Oh, and growing children and pregnant women will need more than this.  So will someone who does a lot of heavy lifting.  But the point is, if low-carb living means you're going to eat globally-scarce animal protein at most meals, you don't have to consume more than your "fair" share (unless it turns out you have a medical need for it).

3.  Fill the rest of the plate with nutritious vegetables.  Flavor them with enough butter, sauce, oil, or cream to give you plenty of energy.    If you want a low-carb, moderate-protein diet, logically you must eat a good deal of fat.  There is nothing wrong with this.   And the thing that will give it to you, along with a nice lengthy eating experience and a sensation of fullness, is the dressed vegetable side dish.  Eat your veggies, and eat them with plenty of tasty, tasty fat -- not an excess, but enough to give you your daily calories.  This fat need not come from animal products.  The bulk of your calories can thereby come from veggies.

Atkins-style low-carb set an initial upper limit on even salad vegetables, which naturally means the dieters felt they had to eat more meat just to fill up their plates.  Some people might need such drastic limits, but I'm betting that most people will do fine eating as much broccoli, okra, cabbage, spinach, collards, cucumbers, cauliflower, asparagus, and the like as they want.   Might as well give it a try.  

4.  Don't waste so damn much food, especially protein.    Here is a sad statistic:  Somewhere between 25 and 55 percent of the food available to people living in North America, Oceania and Europe is simply wasted.*  Thirty-six hundred calories* are available to every American every day; that doesn't count exports.  We eat too much to begin with, and what we don't eat we waste.  

• A lot of these calories are wasted by retail sellers, who have to throw out expired meat and the like.  
• A huge amount is wasted by the restaurant industry; I don't know this, but I suspect that the fancier they are (i.e. the more operating expense they can pass on to the clientele), the more wasteful.  
• But we also waste a lot of food at the household level, by buying too much and cooking too much in the first place, by over-trimming, and generally by being too picky.   

 I've made this point before:  The first place you can reduce your carbon footprint is by wasting less so you can buy less.   What's more, unlike many other ways to go green, you'll actually spend less money (and maybe even time) on the effort.  (A somewhat frightening implication here is that every time we eat in a nice restaurant, we necessarily contribute to the problem.   Don't really want to go there....)

5.  Choose animal products that make efficient use of protein.  One way to compare protein sources is by feed protein to food protein conversion efficiency.    We could get protein by eating cereals and legumes; or we could feed some of the cereals and legumes to animals, and then eat the animals.  How much of the protein in those cereals and legumes can you get back?  We can accept a less-than-100-percent conversion because animal proteins are more bioavailable to us, and also because they come with valuable fats, nutrients, and iron (not to mention that most of us like to eat animals).  But how good can it get?

According to Smil, the best you can do is dairy products, which give you back 40 percent of the nitrogen (a proxy for protein) you fed to your cow.  Aquacultured fish are next, tied with eggs at 30 percent efficiency.  Eating chickens gives you back about 25 percent of what you "spent" in feed protein.  Pork:  only 13 percent.  And when you get to beef cattle, it's pretty abysmal:  five percent.

It does depend quite a bit on how your beef is raised:

Beef production is inherently the least efficient way of supplying dietary protein through animal feeding. ... This inefficiency is irrelevant in broader [nitrogen] terms as long as the animals are totally grass-fed, or raised primarily on crop and food processing residues (ranging from straw to bran, and from oilseed cakes to grapefruit rinds) that are indigestible or unpalatable by nonruminant species. Such cattle feeding calls for no, or minimal—because some pastures are fertilized—additional inputs of fertilizer-[nitrogen]. Any society that would put a premium on reducing [nitrogen] losses in agroecosystems would thus produce only those 2 kinds of beef. In contrast, beef production has the greatest impact on overall [nitrogen] use when the animals are fed only concentrates, now typically mixtures of cereal grains (mostly corn) and soybeans.

Switching from conventionally raised beef to grass-fed beef is expensive, and not even practically possible depending on the grocery options where you live.    But switching some of your conventional pork and beef consumption even to ordinary eggs and dairy is a cheap change, available to anyone anywhere, that can halve your meal's nitrogen footprint while still providing you high-quality protein, enough to support even a quite low-carb diet.

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*Asterisked information comes from the Smil paper.

"My grandfather taught [my brother] cylinder safety by throwing cylinder caps at him every time he moved an uncapped bottle or left a cylinder unchained. They hurt."

Derek Lowe writes another "How Not To Do It" post, this one involving acetylene cylinders.  Alarming explosion video included.

(The above quote is from the comments.)

"Behold the s and p orbitals."

From Derek Lowe:  "Generations of students have learned these as abstractions, diagrams on a page. I never thought I'd see them, and I never thought I'd see the day when when it was even possible. As always, I react to these things with interest, excitement, and a tiny bit of terror at seeing something that I assumed would always be hidden."

Counterbalance.

I just finished reading a book that's been out for several years but that I ignored until recently, when I thought I might need a corrective to all the diet books I read last year while I was losing weight:  The Obesity Myth by Paul Campos.  It's been a while since I deliberately read something that I expected to disagree with -- a practice I recommend heartily!

I was surprised to find that the book was in more than one way a wake-up call for me.

The basic thesis of the book is that our public policy towards obesity, and the amount we spend in public and private dollars to combat obesity, doesn't make sense for three reasons. 

Number one:  there's no credible evidence that obesity in and of itself (except at the extremes) causes health problems.   

Number two:  there's no credible evidence that losing weight in and of itself makes obese people healthier.

Number three:  We're not getting much bang for our buck anyway, since the money and effort we've poured into the goal of getting people to lose weight is not resulting in weight loss.  

I will begin with several significant caveats.  I am not entirely convinced by Mr. Campos's review of medical data.  There is not that much of it; I would like to see a much more thorough and detailed cataloguing than is present in this book, one much more like Gary Taubes' analysis in Good Calories, Bad Calories.  I am also certain that some of Campos's data points raise questions that require answers before one can come to a conclusion.  (One example:  he writes that, excluding extreme thinness and fatness, life expectancy increases as you go from lower to higher BMIs.  I thought:  Now wait a minute -- life expectancy also increases as you get older, and people gain weight as they age, so shouldn't there be a correlation there anyway?)  Third, he seems to sort of selectively criticize and praise the practice of controlling for confounding variables.  I agree that this statistical tool can be used judiciously or maliciously, but Campos does not explain why he says it's justified here and not there.  Has he proven that "there's no credible evidence" that obesity causes illness? I don't think so.

However, I think he does succeed in showing something a bit less ambitious:  that the evidence is not nearly as strong as most people assume it is based on media reports and public policy recommendations.   Five arguments he made struck me as very persuasive, if they are true, of this less-ambitious thesis.  I feel I have to add that caveat because I think Campos needs more evidence to demonstrate that they are true.  But if they are true, I agree with him that they call into question the obesity-health connection.

(1)  To demonstrate that obesity causes health problems, most of the studies had to exclude smokers.  (He says this isn't legitimate; I say it is; but regardless, the following point still stands.)  After you exclude smokers and maybe a few other classes of people, the number of deaths in the studies are small.  Nonsmokers in one study had a less than 1-in-600 chance of dying of cardiovascular disease; thinner nonsmokers were less likely to die than fatter nonsmokers, but the number of excess deaths attributable to obesity alone is perhaps not high enough to justify the effort we're putting into combating obesity.  At the very least, the harm of obesity is likely dwarfed by the harm of smoking.  Which do you suppose our country spends more on:  attempting to lose weight and get people to lose weight, or attempting to quit smoking and get people to quit smoking?

(2)  Public policy advisory boards have an astonishing level of conflict of interest.  It goes beyond the level of "this study was funded by that industry which has a stake in the findings."  For example, he says that a claim of a strong international consensus that BMI>25 was based largely on the report of a World Health Organization panel that "consisted entirely of physicians who run weight loss clinics."  Even if you assume a good-faith effort, could such a group really be objective?

(3)  Campos says that studies that purport to show a connection between weight loss and improved health have not adequately controlled for the effect of improved nutrition and increased physical activity; and news reports fail to distinguish this effect too.  Campos gives an example of a study where participants significantly increased their physical activity and as a result both lost a few pounds and improved some measures of their physical health:  the media reported it as "losing a few pounds can improve your health."   It is now very well established that, independent of your weight, physical activity makes people healthier.  (I wrote about this in my post about reasons to exercise.) Because of that, it's obvious that a study purporting to show that obesity causes poor health must control for physical activity.  Campos says that many of the studies don't have that control. 

(4) Taking all the methods together, the act of losing weight introduces significant health risks that have not been adequately compared to the risk of not losing weight.  For instance, he claims that bariatric surgery is shockingly dangerous (the risk of death within a month of the surgery is somewhere between one in 20o and one in 50!).  Is it really proportionally dangerous not to have bariatric surgery, especially at the lower-BMI end of the market?  He says there are health risks associated with traditional methods of weight loss as well.

(5) Being "BMI-normal" or less appears to cause some serious diseases that obesity protects you from.  Osteoporosis, which can lead to deadly hip fractures, is one such disease; there are others.  When you include these "diseases of mild thinness," does the relative danger of mild obesity start not looking so bad?

Since it's true that physical exercise really is well established as something that improves health, it's apparent to me that it's dangerous to suggest "You should exercise to lose weight, because the weight loss makes you healthy."  Physical exercise is not actually that good at bringing about weight loss.  If someone starts exercising to lose weight for their health, they could really be improving their health and yet not see a weight loss; and will they then conclude that it's not doing any good, and so quit?  Or will thin people dismiss exercise because they don't think they need to exercise to be thin?  

 * * *

Not all of the book is about the medical research.  A large part of it is about the social pressure to be thin.  This is the part of the book that, for me, was a wake up call.  Because I've probably been contributing to it a bit over the past year, as I chronicled my own struggles with weight loss.  I hope on the whole my writing has been positive, because I firmly believe that physical activity and well-balanced, not-excessive nutrition are worthy goals in and of themselves, even if they don't result in thinness, and I want my writing to have reflected that.  Still, I measured my success last year largely in the pounds that came off the scale, and I'm a bit more aware that I emphasized the number too much.

Even in my personal experience, Campos's points ring true.  I've been telling people that I've never felt better since I lost the weight -- but maybe I feel better because I'm so much more physically active, and the weight loss is just a side effect.  

And then there is the lengthy discussion of why we criticize obesity so much.  We say it's about health, but is it really?  Particularly if the medical evidence against it turns out not to be so damning?  Campos makes a strong case that it's about the need for us to have some kind of social pariahs among us, a need to feel superior to others.  (Hoo boy, that hit home.  Consider this post.  And consider that it was after I started to lose weight that I started to write that I was "conquering gluttony."  Look, I'm getting thinner!  It proves I'm becoming a better person!)  

A point I found especially interesting:  Campos, a Mexican-American, argues that the freedom to look down one's nose at fat people has functionally created a way for elite, highly-educated white people to continue to sneer at low-income black and Hispanic people, without having to feel guilty about it:

Precisely because Americans are so repressed about class issues, the disgust the (relatively) poor engender in the (relatively) rich must be projected onto some other distinguishing characteristic... In 2003, any upper-class white American liberal would be horrified to imagine that the sight of, say, a lower-class Mexican-American woman going into a Wal-Mart migt somehow elicit feelings of disgust in his otherwise properly sensitized soul.  But the sight of a fat woman -- make that an "obese"-- better yet a 'morbidly obese' woman going into Wal-Mart ... ah, that is something else again.

He has got a real point (made only clearer by the fact that some upper-class white people would be disgusted merely by the mention of the Wal-Mart, without any reference to obesity at all).

Race intersects with obesity culture in another way I wasn't aware of.  According to Campos, girls and young women in the U. S. who are black or Hispanic are much more likely to have a positive appreciation of their own bodies than are white girls.  They are more likely to evaluate their self-worth independently of their appearance.  They are also likely to have a higher BMI.  And (this is the kicker) at least for African-American women, the denonstrated connection between obesity and poor health is even weaker than it is for white women.   Campos seems to suggest that public health authorities are actively promoting educational campaigns that will sensitize young black and Hispanic women to the dangers of obesity.  If this is true, it is really hard not to come away with the impression that some public health policy amounts to "Let's make black and Hispanic girls feel bad about their weight."   

So here's my final word on the book.  It's not perfect.  It's flawed.  It raises questions that go unanswered.  I'm not convinced of Campos's thesis.  But I think I'm convinced that he raises good points, points that people like me -- who tend toward the weight-obsessed, and who like to tell ourselves that it's "about our health" -- need to read and take to heart.  Some of this seeking after thinness is not necessarily healthy, and it's not necessarily virtuous.

Over the months after I reached my goal weight, it took constant vigilance to keep my weight at 108 instead of, say, 112.  Is it reasonable for me to fear those four pounds?  OK, the truth is I'm really afraid that if I let myself gain 4 pounds, I'll let myself gain 40.  Is that a reasonable fear?  All my clothes still fit at 112.   If I relaxed my diet slightly and became stable at 112, would I be happier or sadder?  And does it make any sense at all to be "proud" of my weight loss?  Even if it's true that gluttony was a big problem before, am I better off if I replace it with vanity and pride?

I think I came away very convinced of one sentence in the book, one of the principles of the "health at every size" movement:  A healthy weight is the weight a person maintains while living a healthy life.  To me, that means while being physically active and eating a well-balanced diet in response to real hunger signals.  Campos derides the traditional approach, but I disagree.  I think traditional "diet and exercise" can help a person create that healthy life; you may have to exercise on purpose in order to get enough physical activity, and you may have to control your eating in order to balance your diet and learn to eat in response to hunger.  I did.  But it does suggest that the number on the scale ought to have less sway on our decisions, personal and public,  and especially on our compassion towards others, than it currently does.

The toxicity of everything.

Conversation at In the Pipeline:  "On the Uselessness of the MSDS."

That's "materials safety data sheets," which are shipped with every substance that can be bought from a chemical supplier, and which famously warn about the horrible toxicity of everything, including sand and distilled water (and, according to a Usenet post linked in the article which is probably an urban myth, vacuum).

It's one of my favorite rants about the problem of over-warning, and it has real consequences that in the end make laboratories safer for lawyers but more dangerous for everyone else; as one commenter points out, when harmless stuff and deadly stuff can both be labeled "Toxic," who pays attention?  And where do you go to get real information about how to protect yourself appropriately from exposure?

One very interesting possibility in which information dissemination appears to be coming full circle:  As the official, government-approved channels of information become less and less useful in real life practice, will those who need useful information turn back to the age-old channels of folklore, hearsay, anecdote, oral legend?  It's "unofficial" but its anonymity (and consequent immunity from lawsuit) shields it from danger-warning-creep.  In the modern age, is this the niche occupied by wikis?  Already underway:  a new chemistry wiki, including a category for personal protective equipment.

So, the nature study book for this year is...

 In a previous post I wrote about my philosophy for teaching nature study to elementary-school kids, and promised to mention the book I'm going to use next year with Oscar.  Here it is: Messing Around with Baking Chemistry by Bernie Zubrowski, from the Children's Museum Activity Book series.  (Little, Brown, and Co., 1981; ISBN 0-316-98878-2)

 There are a lot of books about "kitchen chemistry" out there, and most of them don't really fit my style.  This one, however, is a little bit different.

The usual problem with many of these books of demonstrations -- I do not call them "experiments" -- is that they are all about being impressive, and only superficially treat the deeper reasons why the material works.  A particular handicap is that the level of chemistry knowledge which elementary-school-age children might actually be able to assimilate -- inorganic solution chemistry -- is not readily available in the home kitchen, and most of the solutions that change colors or do otherwise interesting things are, um, toxic.  So the kitchen chemistry books play with baking soda and vinegar and call the one a base and the other an acid, and demonstrate that acids and bases combine to give off carbon dioxide.  Also that this is how volcanoes work.  Um.  No.  

For good reason, introductory chemistry courses in formal study -- high school and college -- do not begin with sodium bicarbonate, but instead begin with inorganic hydroxides.   Nor do they begin with acetic acid, but instead with inorganic acids.  They are simpler systems that readily demonstrate basic principles of stoichiometry. (You try to demonstrate Dalton's law of Multiple Proportions in your kitchen when your reaction evolves a gas.)  

Because this tendency in kids' science books irritates me so much, I never thought I'd use one that relies heavily on baking soda and vinegar.  Well, I spoke too soon.   This one's pretty good.  

For one thing, it doesn't pretend to teach the fundamentals of chemistry.  Instead, what it's teaching are the fundamentals of laboratory practice:  as I wrote in my earlier post, "developing skills of safely handling, carefully observing, accurately describing, faithfully reporting, and logically analyzing."   And I think with a little bit of emphasis on my part it can also teach that "we can learn from our experiences and make predictions about the future, and when our predictions are wrong we have still learned something" -- this is no less than the fundamental postulate underlying all of natural science.

For another thing, it is honest about its limitations.  Zubrowski writes in the introduction, "What this book is about is how to investigate the chemistry of cake and bread making."  Indeed, "how to investigate" -- not "This book will teach you all about the chemistry of cakes" or "this book will teach you why cakes and bread rise" or "this book will teach fundamental concepts of chemistry."  

No, what it does it encourage kids to begin with recipes, change them, and observe the differences in the results.  This is different from most of the activities in kids' kitchen chemistry books -- it's not just a demonstration ("Drop some food coloring in a jar of warm water and a jar of cold water and see what happens!  If you did it right, you'll see that the color spread faster in the warm water!"), it's actually an experiment.   If I require the child to keep a laboratory notebook and run parallel experiments with "control" cakes, then he'll really be doing a real experiment -- much like my soaked-flour-in-the-bread-machine series I wrote about earlier.

The experiments in cake-baking are followed by activities that demonstrate the effects of mixing various liquids with baking powder, and the author does not commit the error of calling these  activities "experiments."  He writes, "If you play with baking powder by itself you will find that it does some very curious things..."  and suggests that the child keep a record of his observations.  To introduce an activity in which the baking powder is mixed with soap water, he writes:  "Now here is something special to try that will show you what happens to the baking powder when it is added to the cake batter."  The explanation:  "The foam, especially in the sudsy water, is similar to what happens in cake batter. The water in the milk in the batter reacts with the baking powder to make small bubbles.  In the sudsy water, air is trapped by detergent film.  In the cake the combination of flour, eggs, and milk forms a sticky dough that traps the bubbles as they are formed."  

This is accurate, unpretentious, and uncondescending writing for children about science (and about cooking).  Compare this to the language in, say, The Everything Kids' Science Experiments Book by Tom Robinson:

Question:  What makes things fizzy? 

 In this experiment, you will produce different combinations of mixtures that react to form fizzy solutions.  You'll start with a baking soda/vinegar mixture and then move on to produce your own safe-to-drink, though not particularly tasty, lemon soda.

Science concept:  Certain materials, when brought into contact with other materials, react in a way that forms bubbles.  Acids and bases often combine to form carbon dioxide, which, as a gas, is what makes carbonated soda fizzy.  You'll be experimenting with several common ingredients to determine which react in this way.

The last statement is an out-and-out lie, and the thing about acids and bases "often" combining to form carbon dioxide is... well... misleading at best.  Not to mention implying that this is how soda drinks are carbonated.  Oh, by the way, one of the "reactions" is dropping a lump of dry ice into some water, which illustrates a physical (not chemical) change.  

Back to Zubrowski.  Because he has kids making small cakes (6 Tbsp of flour in each one), we can use that to discuss the concept of scale-up.  Because he has kids comparing recipes that have been altered by one change at a time, we can discuss experimental design and controls.  There are several activities where mixtures of different quantities are compared, so the importance of measurement and careful replication is demonstrated.  Different brands of baking powder are compared:  since these will, of course, have different prices, there's a nod to economics and to variations in quality control from different suppliers, which Dad-the-process-engineer is really going to appreciate.   A suggestion that the child try making a baking soda cake with orange juice leads me to think the child ought to be able to design his own recipe based on what he's learned from the previous experiments.

  Gas collection systems begin with crude balloons-on-bottles but progress to the child's building a gas generator and a collection system in which the volume of gas can actually be measured.  (Here's where I'm going to go the extra mile and get some lab equipment -- no need to bore holes in rubber balls stuck in the necks of jars when I have access to online retailers that will sell me value-priced two-hole stoppers and Erlenmeyer flasks).  The child is encouraged to try several activities that demonstrate the properties of the gas.  "Experiments?"  No!  Zubrowski writes, "Just what is this gas?  Is it plain old air or does it have special properties?... One of the jobs of a chemist is to find out about things like this.  Scientists have developed all sorts of tests for substances to find out exactly what they are.  Here are some you can try." He goes on to tell how the child can demonstrate that the gas doesn't support combustion, is heavier than air -- a chance to explain molecular mass! -- and dissolves in water to form an acidic solution).  And then, rather than claiming that all these tests prove it's carbon dioxide, he warns the reader "You would need to do other tests to establish this fully..."  (Guess what.  I can buy saturated lime water online.  Problem solved.)

Why does the language matter so much to me?  It reminds me a little bit about my philosophy towards child discipline. With discipline responses, the most important thing to me isn't whether a given technique, or way of explaining things, "works" (appears to give immediate results).  I obviously don't want to choose things that turn out NOT to work, but not just anything that appears to "work" will do.  Ultimately, I choose techniques and language that I am comfortable using:  language and actions that communicate the truth, namely,  that the child is a human person deserving of respect while learning, AND that I as his parent have a real, natural, and just authority over him, AND that I expect him to learn to comport himself more and more as he gains experience and maturity.  If I can't find something that meets both those criteria (truth and effectiveness), I'm going to do my best to try to come up with one, and in the meantime I err on the side of truth over apparent effectiveness.  Because I believe that the truth IS effective, even if it seems to take longer than, say, duct-taping a kid's mouth shut.

For the same reason, I need to use books that use language I can stand to hear.  Language that isn't dumbed down so much that it no longer accurately describes what's physically going on.

So... even though Exploding Color Changing Slime may appear to get kids interested in science, really it only demonstrates that kids are interested in exploding color changing slime.  Which is not representative of "science."  I'd rather introduce children to what workaday science really means:   observation, measurement, recording, communicating, repeating and repeating and repeating, calculating, predicting, testing.  It is not, perhaps, as impressive; it perhaps will not produce wide-eyed wonder, at least not right away.  But it is true, and I think there is a special kind of quiet fascination that some children can find in the thought:  I can do this.  I can discover this.  I can measure this.  I can find it out for myself.  It takes longer to develop, but I think it will stick.

"Lard has clearly won the health debate."

See?  See?  I told you so!

My husband, the Fat Guy (not the Big Fat Guy yet, but he can dream) has always put it this way:  "Look, chemically speaking, human fat deposits are more chemically similar to pig fat deposits than they are to any other animal that we eat.  So doesn't it make sense that we should eat, and deposit in our bodies, the fat that's most like the fat we already tend to have?" 

We get natural lard from the same place we get our grass-fed raw milk.  It's not deodorized, so it has a faint porky scent that initially turned me off, but that I have come to appreciate in many dishes.  I especially love the flavor of cornbread baked in a well-larded cast-iron pan.  It's also my choice for frying tortillas or chicken (not fish though) and it's what I add to the pan when I brown ground beef unless I'm going for an Asian flavor.  I mostly use it for Mexican/Southwestern type cooking, and the occasional French item.  It's my second choice for frying potatoes, after duck fat, which I render myself (I only have to do it every couple of years or so, as I don't fry potatoes very often).

 I typically don't use lard for pie crust (probably its most famous application in white-bread American cooking) but only because I learned to make a butter crust long ago and that's what tastes normal to me.  I think I may have to find a recipe for those Mexican cookies he mentioned.

Finally, a plan for science next year.

Some subjects I don't plan ahead, we just pace through the lessons fast-enough-on-average:   math, spelling, Latin, English grammar, composition, and fine arts, plus reading lessons for my 5yo.   We continue most of these through the summer at a lighter pace.  

Other subjects, the ones I don't do during the summer, I usually set up a week-by-week schedule to spread out the workload evenly through the year and so I can see at a glance what I need to prepare for the upcoming week:  our family read-alouds, American history, world history, religion, and science  nature study.

I was really stressing out about nature study.  "Why, Erin?" you might ask.  "Why, when there are so many fine elementary-school-age science curricula, all boxed up and ready for you to purchase?"  The answer is that I am a bit, um, opinionated when it comes to so-called science curricula.  I can't help it.   I see a hundred flaws in every one I examine.  The problem is I am trained.  

So, for example, I can't stand to use any curriculum that is "Designed for the parent without a strong background in science!"  That eliminates, um, a lot of them.  

And then -- let me pause to add that this is a matter of personal taste, and I do not think less of you if you differ from me on this one -- I am unsatisfied with most science curricula that present elementary school science in a Christian worldview.  It is not just that I prefer not to use a young-earth-creationist curriculum; obviously, not all Christian curricula are young-earth-creationist. Mostly, my problem with them is theological-pedagogical:  they try too hard, and it feels forced and superficial.  Perhaps it's just that, having studied so much chemistry and physics myself, I would personally illustrate the connections among the structure of the universe, Christian revelation, natural law, and mathematics in a different way than the elementary school textbooks choose to do it.   I guess I think the universe so obviously bears the fingerprints of a Creator, and the more I learn about it the more sure I am of that, that it seems extraneous to me to stick God-language to a science curriculum.  Learn about the Big Bang; read Let there be light.  It's much cooler if you allow a child to discover these connections on their own.

And then, I don't like the "Exploding Color-changing Slime" school of science curricula, you know what I mean, nor the especially cringe-worthy subcategory of Science For Girls! in which you explore the science of, say, bubble bath and perfume.  (I have before me a 1959 book called The Challenge of Chemistry:  Careers in Tomorrow's World of Chemistry, by O. A. Battista, in which the chapter called "The Challenge of Chemistry for Women" presents a more liberated world view than does the cover of today's bubble bath science kits.)  The Exploding Color-changing Slime curricula are all about grabbing kids' attention -- they don't build a grammar of comprehension of how the world works.  They are  toys, pure and simple:  and they are fine toys, but not something to build a curriculum around.  (Occasionally a kit comes along that you can really do something with:  last year I had Oscar do a unit study on electrical circuits using the Snap Circuits kit, supplemented with an old library book about electricity, and also many wonderful dinner-table discussions.)

And finally, even if a curriculum manages to pass all those tests, I always find some explanation of something in there that's oversimplified to the point of not being true, and it bugs me.  A LOT.  I guess you could say I am sort of a perfectionist about science.

(Maybe everyone has that about some subject.  I have a friend who's done so much research about emergent readers that she can't stand to use any prepackaged phonics/reading curriculum at all, and was finally forced to write her own curriculum.  A good one, too, I should add.)

The way I see it, there are several definite purposes to elementary school nature study.  (I really prefer that to the term "science" because to me, "science" means doing original -- not contrived -- research and discovery, which is only PART of the work kids are doing when they're studying nature -- and usually it's a pretty small part, if they're lucky enough to do it at all.)  

• First:  it's for learning a lot of random stuff about the world, the vocabulary of nature:  whatever interests the child, from how to recognize the species of birds in your back yard, to what makes the moon have phases, to what we call the reason why stuff falls down.  
• Second:  it's for understanding that mostly, we can learn from our experiences and make predictions about the future, and when our predictions are wrong we have still learned something.
•  Third:  it's for learning that mathematics is wonderfully useful for describing the physical world.  
•  Fourth:  it's for developing skills of safely handling, carefully observing, accurately describing, faithfully reporting, and logically analyzing.  

All of these are to be harnessed in formal instruction at the high school level, but it can all be done informally with a young child.

And you don't have to hit all of those goals every single year, with every single curriculum.

Aaaaaanyway.  I finally found something I am pleased with -- not a curriculum, not a kit -- but an ordinary children's library book, which I've been able to track down from a used book dealer, thank goodness.  We could do almost everything in it with kitchen equipment, but I think I will choose to buy some lab equipment, too.  I think it'll serve all of the above purposes at least a little bit, but especially the fourth one.  I had to sit down for an evening and break it down into a week-by-week schedule, and to my pleasure it filled about thirty weeks, which is just about perfect because it's a "full year" and yet leaves me about six weeks of leeway.

I'll introduce you to the book in another post -- this one's gone too long already!

Exercise vs. antioxidants.

So often, health recommendations are offered in a vacuum:  "Do this, it's good for you."  As if there were no interaction between different "healthy habits," and as if certain habits might not be good for some people and bad for others.

I think there's a general tendency for policy makers to frame health recommendations almost as if they're moral imperatives!  

Well.  Here is an interesting conflict, via Derek Lowe's excellent chemistry/pharma blog In the Pipeline:  Studies seem to indicate that exercise and antioxidants work against one another.  Here's what Lowe writes (my less-technical translation follows):

Now, this is an example of an idea being followed through to its logical conclusion. Here’s where we start: the good effects of exercise are well known, and seem to be beyond argument. Among these are marked improvements in insulin resistance (the hallmark of type II diabetes) and glucose uptake. In fact, exercise, combined with losing adipose weight, is absolutely the best therapy for mild cases of adult-onset diabetes, and can truly reverse the condition, an effect no other treatment can match.

So, what actually causes these exercise effects? There has to be a signal (or set of signals) down at the molecular level that tells your cells what’s happening, and initiates changes in their metabolism. One good candidate is the formation of reactive oxygen species (ROS) in the mitochondria. Exercise most certainly increases a person’s use of oxygen, and increases the work load on the mitochondria (since that’s where all the biochemical energy is coming from, anyway). Increased mitochondrial formation of ROS has been well documented, and they have a lot of physiological effects.

Of course, ROS are also implicated in many theories of aging and cellular damage, which is why cells have several systems to try to soak these things up. That’s exactly why people take antioxidants, vitamin C and vitamin E especially. So. . .what if you take those while you’re exercising?

A new paper in PNAS askes that exact question. About forty healthy young male volunteers took part in the study, which involved four weeks of identical exercise programs. Half of the volunteers were already in athletic training, and half weren’t. Both groups were then split again, and half of each cohort took 1000 mg/day of vitamin C and 400 IU/day vitamin E, while the other half took no antioxidants at all. So, we have the effects of exercise, plus and minus previous training, and plus and minus antioxidants.

And as it turns out, antioxidant supplements appear to cancel out many of the beneficial effects of exercise. Soaking up those transient bursts of reactive oxygen species keeps them from signaling. Looked at the other way, oxidative stress could be a key to preventing type II diabetes. 

Exercise might reduce your risk of diabetes, in part, because it makes your muscle cells produce certain compounds.  Those compounds, however, are known to accelerate cellular damage.  Taking vitamins that deactivate the "damaging" compounds also deactivate the good effects of the compounds.  

The whole post is worth a read.