The ability to taste bitter flavors probably didn't evolve as a self-defense mechanism


Headline typo?

I’m pretty sure there was no ‘learning to enjoy’ coffee for me - at some point I asked my parents for a cup of coffee, I poured myself one, I liked it. I know many people started only liking it with sugar, and gradually reduced the sweetness, but I’ve never cared for sweet coffee. Same with beer and red wine - I don’t remember ever not liking those tastes a a child.

My daughter, at about the age of 2, started wanting to taste my beer, and I was surprised to find she really enjoyed it - and while I don’t generally go for the hop-bomb IPAs, I certainly don’t drink the cloying sweet American lagers either. For a while, I had to keep a close watch on my whiskey, as she was only allowed to dip her finger in it to taste a drop - she liked whiskey so much she might have downed a glass given the chance.

A year or so later, she’s not much interested in booze anymore - she’ll occasionally ask for a sip of beer, but that’s about it. I’m not sure what changed.

The ability to taste bitter flavors probably didn’t evolve as a self-dense mechanism

Based on the astute observation about the frequent pretentiousness of IPA and espresso drinkers, I think you’re right about the typo.

That “didn’t” should have been a “did”…


I find the hypothesis confusing, maybe someone can clarify it for me.

They found that the mutation to detect bitterness emerged about a million years ago, before humans were around (and certainly long before there was a difference between hunter gatherers and herders).

Then they expected there to be a difference between the hunter gatherers and herders?

They have no mechanism as to why either of the groups would lose the trait, as it doesn’t confer any disadvantage. If it conferred no advantage the genetic drift eventually could make it disappear, but they already know that non-hunter gatherers still have the trait. So…?


I don’t like beer, but I love bitter herbs. Honestly, aren’t a lot of really nutritious plants bitter? Why would it be bad to be able to taste them? It seems like actually liking the taste would make one more likely to eat them, and in my experience there’s a big difference between the edible bitter herb taste and the wow this burns like I’m not meant to eat it taste of, say, rhubarb leaves.

I’m not convinced. Modern indigenous people are not analogous with archaic Homo sapiens, nor is the flora of a region in 2013 analagous with the flora 400,000 years ago.

I m probably missing something here but I wonder if it is not so much bitterness per se, but rather the ability to taste sweetness that is the issue? Bitter is the polar opposite of sweet,; perhaps it is not possible to have a taste indice for sugar without it’s negative indicator? Sugar represents energy, so justifieing the sweet taste through evolution would make sense…

Not having read the full study, I think these conclusions are confusing as well. Firstly tribal groups are not necessarily insular, and distinctions can be more culturally-based than genetic (the Hutu and Tutsi people come to mind). Secondly social behavior is not necessarily dictated by genetics. In addition to producing bitter alkaloids, plants also create compounds like capsaicin to deter their consumption. However we have domesticated and cultivated these plants so that bitterness or spiciness become pleasant (e.g. coffee). Compound this with the fact that through mimacry, some plants may be bitter and not poisonous at all.

Again these are just some thoughts without access to the full article. Not doubting the findings of the research team, but the conclusions being drawn by NPR.

I remember a rather vague theory based on the fact that “harmful” plants can be beneficial at certain times. Cruciferous plants, for instance, have isothiocyanates, among others, which block cell division. Pregnant women, who generally are in favor of cell division for the sake of their fetuses, often eat less than non-pregnant women, due to morning sickness. Kids often avoid the bitter plants while they are growing. Non-pregnant adults eat more of the plants as, in our case, blocking cell division and inducing apoptosis is more often knocking off cancer cells than retarding growth, and it’s advantageous to add those plants to our eating habits.

Please don’t critique this too harshly as I’m not really awake yet and haven’t marshaled the relevant links. Here, have a random paper on the plant compounds. And an article on morning sickness.

Of course I have no idea if the many bottles of chemicals mentioned in the original article included any of these sulfur compounds as I haven’t accessed the full article. .


The substances that cause the bitterness are often toxic - theplant’s self-defence mechanism against pests.

Potentially, without the ability to taste bitterness, we wouldn’t be able to determine which foods are bitter at the delicious kale level, vs. the risk-of-cyanide-poisoning bitter almond level.

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You’re right, it should be ‘flavours’.


You’ve eaten rhubarb leaves and lived to tell the tale?

Sweetness is not the “polar opposite” of bitterness. If it were, bittersweet tastes would be impossible to achieve - the bitter chemicals would neutralize the sweet chemicals, until all you could taste would be whichever remained unreacted.

Sweetness is an indicator of the presence of sugars (notwithstanding the few things like stevia, that trick us into tasting sweetness without the presence of sugar). The polar opposite of that is the absence of sugar - not bitterness, just the absence of sweetness.

Bitterness is an indicator of the presence of chemicals with other chemical characteristics, unrelated to being sugars. The polar opposite of of that is the absence of bitter substances - not sweetness, just the absence of bitterness.

If anything, you could say bitter is the polar opposite of sour (acids taste sour; alkaline things tend to taste bitter, and they really do neutralize one another).

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Rhubarb leaves are not drop-dead-from-a-nibble poisonous.

It’s possible to make yourself good and sick, even to kill yourself eating them - but you’d have to eat a large amount to achieve either.

I was being dramatic, but you’ve ruined it now with your accurate information.


Sorry, I meant to say - they’re like those toadstools with transdermally active poisons. Just touching the sap when you cut rhubarb will surely drop you if you haven’t got rubber gloves on.


In terms of flavour they counter each other - lemon juice is a powerful tool in the kitchen for taking sweetness down a notch - but I know what you mean, I wouldn’t describe them as ‘opposites’.

Makes sense.

In the past few years, scientists have started to realize that bitter taste receptors are all over the body, Tishkoff says. These receptors have turned up in cells in the gut, lungs and even the testes.

That seems like an interesting story itself.