Eggs

I just read an article which annoyed me.  Actually, take that back, I had absolutely no problem with the short little comment masquerading as an article.  It was the comments.  The sanctimonious comments made by people who are sure that they know all there is to know about nutrition and what one should and shouldn't eat and feel perfectly comfortable advising and judging their fellow humans on what they should be eating.  And this was the least of it.

(For this post we are going to completely put aside the MD that sometimes lurks after my name and the fact that I am funded, sort of, by a school of public health)

The real fact? We don't know jack shit.  The best argument I've heard is the one that works for almost everything in life.  Moderation.  (Almost anything because there is no such thing as a moderate amount of cocaine.  Its just plain bad, sorry to any recreational crack users)

There are SO many theories about what one should and shouldn't eat.  And some of them are so extreme that most people know they're ridiculous.  Some of them, though, come with the stamp of medical studies.  I will say right now I haven't read all of them.  But, generally speaking, you ask a large number of people what they ate, you know, say, over the past 20 years how often did you eat x,y,z.  And then they check a couple years later on how many had heart attacks, or what their cholesterol level is.  You control for everything you can think of that might also influence your outcome, and you get a teeny tiny effect, which, since you asked 10,000 people turns out to be statistically significant.  There is a difference, a big one, between statistically significant and biologically significant.

One is easy to measure p<0.05 (although many times across different disciplines the idea of correcting for multiple testing gets lost in the shuffle, and can be difficult to determine anyways because multiple researchers use the same dataset.  Each time you probe that dataset its an independent test, but you don't know how many tests have been done on it, or will be done on it.

Biologically significant is totally open to interpretation.  If eating eggs every day leads to a couple points higher on your cholesterol level (again haven't read the studies) do you actually care?

Let's remind ourselves that we don't really know the significance of cholesterol anyway.  Certainly people with way high LDL have heart attacks at early ages.  Other than the tiny proportion of people with genetic mutations (I'm one of them) no one will get there LDL that high.  Food won't do it.  The inbetweens? we don't know.  So there's no sign of anything bad related to too low cholesterol, so let's bring everyone's levels down.  My cholesterol level has been above the high level (where statins would be recommended) from the first time it was tested when I was a young teen.  That's 17+ years, with well above recommended levels, no heart attacks.  Moreover, my mom, who clearly gave me the mutation, has similarly had 'too high' levels her entire life.  She's going strong, clean stress test and she decided on jazzercize when she got bored with running.  She's 68.  No heart attacks in sight.  My grandmother, died at 78, yes, from a heart attack.  There were no statins then.  If without drugs and cholesterol levels over 300 I die at 78 from a heart attack, I think I might wait on attacking that cholesterol level with all ammunition possible, rather than spending 30 years on a drug whose long-term effects are absolutely, completely unknown.  I'll also wait on completely adjusting my diet on basis of science with little actually known biological significance.

Aside from significance, those kind of studies also have obvious problems with recall bias.  Do you remember how many times a week you ate red meat, fish, green vegetables, eggs, red wine, black tea, coffee, etc. or over the last month, year, 20 years? probably not.  So you guess.  And if you really love red meat, you might guess high on that.  If you know green vegetables are supposed to be good for you, you might guess high on that too.  You might not count tuna sandwiches as fish because you think that's not what they mean.  And maybe it isn't what they mean.  Hopefully these researchers are very specific about these things.  But we don't know.  All we hear is red meat is bad and green vegetables are good.

The other type of study is, keep a daily record of everything you eat for x amount of time.  After which point we check how healthy you are.  But wait, you didn't ask them to do this for 60 years right? (Well, they might have in Framingham Heart Study.  Hopefully they didn't pester them with daily food diaries, but they probably have pretty good data for the time since we started caring what people eat) So they're not measuring whether people heave heart attacks, strokes, or die.  They're measuring biomarkers.  Cholesterol, Blood pressure, glucose, CRP maybe.  And then if these are different, we link that to the fact that we think these are related to bad outcomes down the road if people continue their current habits.  Okay, hypertension is definitely related to bad outcomes.  High glucose is obviously related to diabetes, it defines it.  But you better have multiple measures, they better be fasting.  You'd best test everyone at the same time of day, it varies more in one individual throughout the day than it probably does between your subjects.  This is not easy to do.

And of course there is weight.  Obesity is bad.  Little changes in weight? Probably not bad.  But if we associate eating certain foods with gaining weight we all freak out and avoid like the plague instead of becoming a little more active.  But I'm not even going to touch the weight loss crap with a 10 foot pole.  Calories in = calories out = stable weight.  And people are thinking, but this contorted system works and others don't.  Actually that contorted system either messes with your body in contorted ways (catabolic state) or just messes with your head.  You can eat whatever you want as long as its a ton of vegetables on a list.  Why? Because said vegetables really don't have many calories, so rather quickly you're hungry again and you go eat another mountain of vegetables.  You could have just gone with the salad bar without someone telling you it was weight loss.  Duh.

So these comments were about how eggs weren't recommended.  How someone always put leafy green vegetables with it because those are good.  I happen to like steamed spinach mixed into scrambled eggs so I'm on board with that one, but that's just cause it's tasty.  Someone else who likes poached eggs, and another commenter mentioning that these are associated with infection.  Ummmm...

Yes, raw, undercooked poultry and their eggs carry salmonella.  Yes, raw ground beef is a nice carrier for E.coli.  Anyone noticed that the recent outbreaks tend to be in spinach or situations where there was no meat period? Infection from eggs? .6% chance from a contaminated egg, and that's mostly from the shell.  This is a tad detailed, but if you think about it, the transmission from shell to part of egg actually eaten is when you crack it.  The outside of egg comes into contact with white of egg, which is then cooked in a poached egg.  You'd have to seriously mess up the cracking for the shell to come into contact with the yolk.

That said, people die from it, and that obviously sucks.  Just like E. coli (where only certain variants cause serious disease) it is children, whose GI tract probably hasn't fully developed its rather spectacular immune system, and immune-compromised individuals (cancer, AIDS, autoimmune diseases on therapy) who get seriously sick and die.  So why do restaurants cook the hell out of their ground beef? To make sure you don't sue them.

There's all kinds of other things out there.  Antioxidants.  Good? Maybe. If you grill meat the charred bits have carcinogens in them.  Yes, but is eating a little charred meat (if you like it) going to give you cancer? Probably not.  Once we say something has things in it that cause cancer you get people freaking out.  Well, except I don't think the similar finding in french fries has slowed down their consumption.

I'm sure you're getting bored.  Or maybe that's just me.

I think everyone eats what they want to eat as long as it helps them feel good about themselves.  Your diet choices can be due to animal rights, or to arguments against pesticides, hormones or antibiotics, to support local food because you think it requires less energy and you want to decrease carbon footprint (not necessarily effective since it can require more energy to grow the particular food you are buying nearby rather than across the country).  You can want to feel superior in your up to date knowledge of the science literature (if so, please read the papers, not the news reports).  This particular one is tough since you have to change the foods you eat on a virtually daily basis.  One interesting one is to match what we eat to what humans ate millions of years ago.  Grains and legumes and vegetables, with occasional meat when the men actually dragged some back.  This seems like an argument constructed to support a diet that's perfectly reasonable on its own.  The problem with the evolution thing is that presumably humans have evolved in lock-step with their environment and eating behaviors.  So to the extent that this has anything to do with natural selection we should be good.  Unless you ate something like a poisonous frog that took you out of the gene pool subtleties in food probably aren't involved.

I don't even follow my own precepts.  Moderation.  That would mean eating a variety of food.  I mostly don't eat very much.  Which seems to alarm some people.  It ends up being fruit and yogurt, bread and cheese, some sushi. Which sounds healthy but its totally by accident.  The only things I will take active steps to minimize are salt and artificial additives.  Why? Well, the salt is partly pretty easy because I wasn't raised with much salt in my diet so its easy to add little or no salt to any food I prepare.  Of course, the salt and the additives that we are getting that could be a problem are in processed food.  I figure I am at the moderation point in salt.  There is so much in processed foods that it would tip me over to excess fast if I ate much of them.  And then we have preservatives and sweeteners.

I actually have a good reason to avoid anything we're actually willing to call artificial in food.  (I think a lot of things slip by.)  I get migraines from artificial sweeteners.  Once you realize that something directly causes you to have a painful experience, by all means, stay away from it.  So if you get salmonella from an egg, I wouldn't blame you for never eating another egg, even if strictly it wouldn't be rational.  Similarly, if eating something makes you feel really good go for it.  Just not pot brownies.  That doesn't count.

Just don't get all self-righteous and act like whatever you've decided to do is the only way to eat.  Don't shake your head at the perceived ignorance or thoughtlessness of everyone who just eats, without a philosophy behind it.