Food Fads and Fears

I've been reading the book Fear of Food by Harvey Levenstein.  It is a fascinating read, chronicling the history of food fears and fads that hit Americans in the 19th and 20th centuries.  I have a few quibbles with some of the material in the chapter on "Bacteria and Beef", but overall, good stuff.

One passage showed how at least one version of the Paleo diet had been advanced since the early 1900s for many of the same reasons it is advocated today, almost 100 years later:

In 1920 Fleischmann’s urged eating its yeast cakes because ‘the process of manufacture or preparation’ removed from many foods the ‘life giving vitamine’ that provided the energy people needed. ‘Primitive man,’ it claimed, ‘secured an abundance of vitamines from his raw, uncooked foods and green, leafy vegetables. But the modern diet - constantly refined and modified - is too often badly deficient in vital elements.’

Levenstein also chronicles the emergence of food scientists and nutritionists who often had significant effects on dietary fads and public policies.  It is remarkable the hubris with which many of these men made dietary advice and public policy, particularly because we now know they were often quite wrong in their scientific knowledge.  Whether it was Metchnikoff and Kellogg and their views on autointoxication and the merits of yogurt, or Horace Fletcher's method of chewing to "Fletcherize" food,  or Harvey Wiley and his war on benzoate of soda, or Elmer McCollum and his promotion of acidosis, or Russell  Wilder's belief that thiamine deficiencies would cause the nation to loose their will to fight the Nazis - there seems to be a continual stream of people willing to use scant evidence to promote their favored cause to promote public health.  Not just idly promote - but with often with righteous indignation and certitude of belief.  I have no doubt many of these men passionately believed the diets they promoted but that didn't ultimately make them right.  

Levenstein writes, in the midst of concern of lack of vitamin consumption in 1941, that

The New York Times said, ‘The discovery that tables may groan with food and that we nevertheless face a kind of starvation has driven home the fact that we have applied science and technology none too wisely in the preparation of food.”

Unfortunately, something similar could be said about how applied science and technology have often been used none too wisely to promote various public policies and best selling books.   

It is true that science has progressed and we know more than we used to.  One of the things we've hopefully learned is that we often need to exercise a bit of humility.

Is Food Addictive?

The Neurosceptic at took on that question in a recent blog post. The author discusses a recent article arguing that dopamine release in response to food is evidence of food-related addition.  Here are the problems with that thinking:

If you view addiction as essentially about reward (pleasure), surely that means that anything pleasurable could also be addictive? Or to put it another way, if you’re saying that addiction is the direct consequence of over-indulgence in a reward, then aren’t you saying that reward itself is ultimately what’s addictive?


If everything from food to friends to music are rewarding because they trigger dopamine release, then surely all of those things could be ‘addictive’. If ‘reward’ is essentially monolithic, and the various kinds of rewards differ only in how powerful they are, then everything’s addictive to a degree. The more fun, the more (potentially) addictive. The better something is, the worse it is.
This seems to me to be the logical conclusion of this approach to addiction. Let’s call this (very widespread) approach neuropuritanism.
The funny thing is that this idea – for all its medical, neurobiological, scientific language – actually undermines the concept of addiction as a ‘disease’ and reduces it to what amounts to a moral failing – it casts addiction as over-indulgence. The Sin of Gluttony, if you will.

The (Not So) Extraordinary Science of Addictive Junk Food

The New York Times Magazine ran a feature story this weekend by Michael Moss entitled The Extraordinary Science of Addictive Junk Food.  There is really so much that could be said about this piece (and probably the forthcoming book by Moss), but for now, I'll just leave you with the letter I sent to the editors of the NYT:

Michael Moss’s over-wrought piece on the “Science” of addictive junk food misses some key facts.  Around the time the executives of Big Food were in their clandestine meeting, regular folk were voluntarily cutting back.  CDC data reveals that the average weight of 40-49 year old women fell 0.2 lbs over the last ten years.  In the last four years, the average weight of men in this age range went down 1.7 lbs (women’s weight fell by 3.3 lbs).  It seems that the addictions cooked up by nefarious food scientists are waning.  Or maybe they weren’t addictive at all.  I gave up regular Dr. Pepper in 2002 when my pants began fitting too snugly, and I can’t recall any withdrawal symptoms.  If Big Food isn’t in their lab trying to create new tasty treats I want to try again and again, I’m not sure why they exist.

So What if the Poor Eat More Salt?

A new study was released showing that poorer people in Britain consume more salt than the rich.  I don't doubt this is true.  But, I seriously question the inferences drawn by the researchers and other commentators.

The authors of the study indicate that:

These results are important as they explain in part why people of low socio-economic background are more likely to develop high blood pressure (hypertension) and to suffer disproportionately from strokes, heart attacks and renal failure.

Really?  Isn't poverty correlated with a bunch of other bad things that can result in adverse health outcomes?  There is strong evidence that the poor smoke more, drink more, eat fewer veggies, weight more, and on an on.  Yet, we are to believe that the culprit for all their problems is salt?  Aren't there underlying factors, such as the evidence that the poor have lower discount rates (i.e., they value the future less), that are driving all these behaviors?  In short: correlation with salt intake and poverty doesn't  prove anything is causative.  Yet, we'd need to know causation before public policies are recommended.  Nevertheless, the researchers say that:   

widespread and continued food reformulation is necessary through both voluntary as well as regulatory means to make sure that salt reduction is achieved across all socio-economic groups.

But, where is the evidence that such regulations or voluntarily actions would have the intended effect?  There is actually quite a lot of debate (see here or here) about the health impacts of reducing salt in our diet.  

And what would be the costs of such voluntary or forced actions?  It might do good to ask why the poor eat more salt in the first place?  One answer is alluded to in the press release: the poor are much more likely to work in jobs that require manual labor.  You know - jobs that make you sweat.  More sweating requires more salt intake.  Another answer, also alluded to in the press release, is that the poor might eat more processed food which often contains more sodium.  What the release fails to discuss is that, given job and family demands, the value of convenient, processed food might be relatively higher among the poor.  Restricting access to such foods might very well reduce salt intake but it is unlikely to make their life measurably better.  It is easy for a relatively rich researcher with a relatively flexible job to say that the poor would be better off if they cooked more fresh foods and stayed away from convenient, packaged foods.  I suspect a single mother working two jobs would have a different opinion.