Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
5 Apr

Seasonality for the Birds

PheasantLast week, we determined a common thread of seasonality running through historical fructose consumption. Warm weather with plenty of sunshine generally meant fruit was available. Those living in the tropics (as we humans did for most of our history) thus had year-round access to sweet fruit, while cold climate Grok had seasonal, intermittent access. Plus, there are many symptoms shared between folks with vitamin D deficiency and fructose-induced metabolic syndrome. Eating fruit seasonally (if you’re into that sort of thing) in the modern world, then, probably involves getting some sunlight with your berries.

What about other clearly seasonal foods – can they be consumed freely and wantonly?

Consider birds. The bird is especially sensitive to environmental and seasonal fluctuations, as anyone who’s ever been woken up by hungry birds chirping at the morning light can attest. You’re all familiar with the “flying south for the winter” phenomenon, and you’ve probably seen the highly efficient flying V formation employed by migratory ducks or geese.  They’re just following the food. Ever watch “The Endless Summer”? It’s like that, except with grubs and seeds instead of big waves. Not all birds are migratory, though. If they can stay put and get enough food to survive, migration to a warmer climate is unnecessary.

We’ve been eating birds for millennia. They can be a bit hard to catch, sure, but the payoff is incredible: juicy thighs, fatty skin, delicious edible bones. And if you were to nab a big one like an ostrich or a wild turkey, that’s dinner for a week! Birds are definitely seasonal, though, and depending on where Grok was living, bird meat wasn’t always available. Does that mean poultry should only be eaten seasonally? Of course not. Meat is meat (well, dark meat is definitely not white meat, but it’s all meat).

What about the eggs? Egg laying is absolutely seasonal. Birds are wired to lay eggs in warmer weather, when food abounds. Even birds that stick around all year long aren’t constantly laying eggs. Grok undoubtedly loved eggs (he never had to deal with the egg yolk fear campaign), but he didn’t have steady access to them. Still, if eggs are just another form of meat, there shouldn’t be an issue with steady consumption of them… right?

Maybe, but there’s a bit more to the story.

Remember that health issues with food generally arise when we eat food that really doesn’t want to be eaten. Take grains, for example. Grains house the little plant embryos; in order to deter consumption and ensure growth, the grain employs lectins and other anti-nutrients. These are chemical self-defense mechanisms that can trigger auto-immune diseases and irritate the intestinal lining. Meat, on the other hand, comes with claws and teeth and legs (and sometimes poison) to dissuade consumption. Once the animal is dead, though, it’s dead. It no longer cares whether it’s eaten, so dead meat is pretty safe to eat. Just watch out for the ostrich’s legs when it’s alive.

What about eggs? Eggs are a different beast altogether – almost like a meat seed. A meat precursor. An egg has no active physical defenses (unless the mother’s around). It can’t sprout legs and run away. It does have the shell, which appears fragile but is actually incredibly resilient. Note the shape, which varies according to the nesting environment; cliff-nesting birds have the most conical eggs, ensuring a loose egg will roll around in a tight circle rather than roll off, while hole nesters produce more spherical eggs. Shells are meant to keep predators, faunal and microbial alike, away from the interior goods.

If you get past the shell, there’s another line of defense: the white. The egg white serves three purposes.

It stores protein for the growing organism – about 50% of the total egg protein.

It helps transport nutrients into the growing embryo.

It protects the egg from microbial attack.

That last one is where things get potentially hairy for us egg-loving hominids who only had historically seasonal access to them. Because the egg is a stationary, otherwise helpless bird “seed,” it has selected for toxic, antimicrobial proteins in the white to bolster defenses. In fact, other than ovalbumen, which accounts for 54% of an egg white’s protein content, the thirteen other proteins in a white are antimicrobial. They aren’t explicitly meant to hurt mammalian interiors, but what harms the microbes can hurt us, too.

Lysozyme is the most problematic egg protein, but in a strange, roundabout way. By itself, pure lysozyme is probably harmless. We even produce it in our own bodies. But because it has an alkaline isoelectric point, it can form strong bonds with other egg white proteins. It binds with the white’s other protease inhibiting proteins, like ovomucoid or ovoinhibitor, to avoid digestive breakdown by protease enzymes, and it can form hardy, potentially harmful protein compounds that pass through the intestinal lining and produce or exacerbate autoimmune or digestive issues.

Now, certain animals can adapt to chemical defenses, given enough time and exposure. Birds, for example, are wild seed-and-grain-eaters. They’ve adapted to the lectins given their steady exposure to them. Primal folks eat a lot of eggs. I’m one of them, and I probably eat them five days out of the week. But how long have we been eating eggs year-round? The first fowl domestication probably occurred 8,000 years ago in Thailand with the red junglefowl, but I imagine year-round egg production took a bit longer to perfect. Have we adapted to year-round egg consumption?

I’m not sure. Egg white allergy is relatively common, ranging from between 1.6-3.2% of the population. According to Cordain, it’s the second most common food allergy. That, plus the inherent purpose of the egg white itself, makes me suspect that there is something there. I don’t think year-round consumption of eggs is a problem for most people; I just think that certain individuals may be sensitive to the egg white protein, while others can down them without issues. I have heard of people developing egg allergies or negative reactions in adulthood, but that usually happens with people who eat a ton of eggs. I don’t hear about people developing lamb allergies.

Egg consumption doesn’t have to be seasonal, but our understanding of eggs is informed by the seasons. Seasonality merely limited historical access to eggs, which in turn limited our ability to develop universal adaptations to egg whites. That’s it. Frying up a scramble in the dead of winter may not be historically accurate, but who the hell cares? It’s not the timing of consumption that matters, but the frequency – and even that isn’t set in stone. If you love eggs, don’t stop eating them. They’re a fantastic source of fat, protein, and vitamins. If you have a preexisting autoimmune issue, though, filling up on eggs could make it worse. And if you start feeling like crap after every egg meal, you should probably ease up. Don’t make eggs your primary protein source (I’m talking five or six eggs each meal), and most of you should be fine. Just be aware that the ability to eat a dozen eggs every day is relatively novel, evolutionarily. I’m not saying that problems will always arise when we introduce dietary novelties, or even that they’ll be more likely to arise. I’m just saying that they may arise for some.

(I find it highly ironic that the only thing you really have to worry about is the egg white. Hmm, next time I’m at a diner I’ll try to order an egg yolk omelet. It might be even cheaper.)

By now, it’s clear that the seasons affect everything: organisms (sentient and inanimate) respond to changes in temperature, rainfall, weather, availability of sustenance by adapting, migrating, or dying; certain geologic features are molded by rain, wind, or glacier, while coastlines are obscured or revealed by changing sea levels. It’s not even so much that things are affected by seasonality so much as they are imbued with it. You know how space and time are forever linked and wholly dependent on one another? How the two are contextual and relative? Think of the seasons, life, and this planet the same way. It’s all linked.

Anyone have egg white allergies? Did you develop them recently, or have you always had them?

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. Huh? “Since I eat a paleo diet…I don’t think I am eating food products that contain eggs”

    But eggs are “Paleo” and, in fact, “Primal”.

    Eggs are not dairy (dairies are where animals are milked – don’t try milking chickens!). The two are conflated constantly.

    Eggs are pure protein and certainly available to our most distant ancestors. Making them a “proper” Paleo food. Unlike dairy, which therefore is not “Paleo” but is considered “allowed” under the “Primal” banner which is more about informing our decisions from the evolutionary norm than sticking to only what was available in palaeolithic times. (There are a lot of “labels” around this stuff eh? :)

    Someone might need to avoid eggs if they have an allergy/intolerance to them specifically or they are dealing with some kind of autoimmune related disorder. But there’s no reason to consider them “non Paleo/Primal”.

    RedYeti wrote on August 1st, 2011
    • Hey RedYeti, I didn’t say eggs were not paleo, by food *products* containing eggs I mean cakes, breads, sauces, etc. things which are processed with eggs normally.

      I don’t eat these food *products* except on my treat day, but I do eat eggs once a week – boiled/scrambled or in a crustless quiche.

      Joel wrote on August 1st, 2011
  2. Ah! Sorry my mistake – but still worth me saying in case anyone else reads it the same way :)

    RedYeti wrote on August 1st, 2011
  3. Hi,
    I just started this eating plan 2 weeks ago, but over the past year I’ve noticed I get terrible stomach cramps within an hour of eating eggs, fried, scrambled,or poached & it lasts a couple of hours & I just feel horrible, yet I do not have any problem if the eggs are in baked goods. I am 66 yrs old & can’t figure out why I would suddenly have this problem after eating eggs for 65 years. I’ve read that hard boiled eggs might not be a problem, but I’m not in any hurry to try it. Any insight would be appreciated.

    Fran wrote on May 18th, 2012
    • (Wow – this turned into a massive comment – hopefully it may help more than one person with egg related problems though…)

      It could be many things. Developing an egg intolerance seems common.

      However here’s something from my own experience – but bear in mind this may be nothing to do with your own:

      I experienced something very similar with eggs though it was in the context of a broader problem with digestion (likely to do with lots of antibiotics taken due to contracting Lyme Disease – fun, fun, fun). If you have no other digestive issues, this is probably not for you.

      The immediate fix for it was simply taking some good, strong digestive enzymes along with a fair bit of Hydrochloric acid + Betaine supplements.

      But not just any digestive enzymes, the ones the worked were Garden Of Life Omega Zyme 2 per meal (thanks to Cillakat for that tip!).

      HCL+Betaine should be in a capsule not a tablet since, if you need HCL, you have trouble breaking things like tablets down!. So something like Thorne Research’s caps work well there. The Thorne caps come in a much larger and more economical size too. Working out the HCL dosing is described on an excellent Chris Kresser article.

      My story is far more complex than is suitable for a comment thread on eating seasonally but I’d add that increasing salt intake (teaspoon a day) also helped (salt contains chlorine -> hydro/chloric/ acid).

      RedYeti wrote on May 19th, 2012
  4. At 21 I was pregnant with my first child and developed a serious aversion to eggs. I couldn’t look at them, smell them, eat them without being sick. I even started having an aversion to cooking breakfast meat, and then all meat, by association. Since then I’ve had a love/ hate with them. After my son, to lose those extra pounds, I hit the gym every morning, followed by a couple of eggs with onion, garlic, peppers. Didn’t seem to have a problem with them then, but it’s been on/off relationship. In the last year or maybe 2, I’ve noticed that anytime I eat eggs, or even products made with eggs. I have extreme nausea and stomach cramps for about 3/4 hours afterwards. It was my breakfast of choice being mostly primal, so some days it’s not only hard, but frustrating. This post made a lot of sense and has encouraged me to just give up my egg fight. I obviously shouldn’t be eating them. My body has rejected them and I need to listen to it. On a side note, much later in life, my mom developed the same issues, she was almost 50. My grandma also told me the other day that she isn’t a fan of eggs either, so possibly something genetic? I still feed them too my kids occasionally because they’re quick, easy, and healthy, but I wonder if they will develop problems too. Do you think I should cut them out of their diet as well?

    Jessica wrote on October 10th, 2012
  5. Thanks for the article! I’ve been aware that eggs were seasonal for quite some time, and, that they change with the seasons (in French culinary schools they learn different recipes for spring eggs, summer eggs, and fall eggs), and have been concerned by the intense egg consumption I so often see in Primal/Paleo diets.

    Another hypothesis for why there are so many egg allergies is that egg white protein is a common ingredient in vaccines. If you give it the body often enough, while coupled with something intended to create immune memory of “this is bad; attack it”, eventually the immune system will “see” the egg white protein and develop a response to it, too.

    Personally, I LOVE egg yolks, but have never really liked the whites much. Though I do eat them, because I was raised with strong inhibitions about wasting any food. Maybe now I’ll feel more free to get rid of them…

    We usually eat duck eggs–bigger yolks! (I recently found out, different fat profile in said yolk, at least according to the USDA tables: more omega-9 in duck eggs–maybe not as good a choic,e therefore. But they sure are delicious!)

    Erica B. wrote on April 26th, 2013
  6. I have been eating eggs 5-7 days a week for many years (even before PB I always had some protein for breakfast along with one slice of toast). Since PB I eat slightly more of them but only very slightly more. For the last few years I have been dealing with ahem…. flatulence. When I started a primal diet it actually calmed down for a while but then in the last 4 or 5 months it has worsened and worsened to the point where it was becoming a real problem!

    I thought maybe it was dairy, maybe I need more probiotics etc. etc. Yesterday I wasn’t well and didn’t feel like breakfast when I made it for the family so I ate something else a bit later. No wind! (Or very little, what I would consider a normal amount). So today I again had no eggs for breakfast, again all calm on the western front (or should that be southern front?)

    Anyway, I am definitely going to drop the eggs for while and then after a couple of weeks reintroduce them and see what happens. If they are definitely the problem it’s a real shame as they’re a great food, but I would rather be rid of this problem! Also, I have read that for egg intolerance (rather than allergy) you can stop eating them for a few motnhs and then try them again and they may be ok.

    Vanessa wrote on April 2nd, 2014

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