Yesterday I cooked some chicken. Today I reheated the leftovers. While eating them, I had a gruesome thought: Warm food is more pleasant than food at room temperature. Could the evolutionary reason be that it is better to eat freshly-killed meat (warm) than meat killed yesterday (room temperature)? Or did a preference for warm food evolve because it caused us to prefer cooked food (sterilized) to uncooked food (unsterilized)?
Sure, thermoregulation is involved. We like warm food more when we’re cold; we like cold food more when we’re hot. Michel Cabanac has done brilliant experiments about our changing preference for hot and cold environments. But there is an overall preference for warm food. We like warm food even when we’re not cold.
In spite of thousands of books and articles promoting this or that “natural” diet, it has been incredibly hard to determine what our ancient ancestors ate, the diet that presumably fits us best. One way has been to ask what modern-day hunter-gatherers eat. Not only do their diets vary widely but also they are clearly not typical: They live in meager environments. So that is hopeless, although Weston Price showed that there was a lot to be learned by studying earlier foodways. Price was surprised to find how much those ancient foodways differed from each other yet all produced good health.
The most basic questions about our ancient diet remain unanswered. Did our ancestors eat lots of meat (savannah evolution) or lots of fish (aquatic ape theory) or neither (vegetarian proponents)? In spite of looking, Price never found a group that ate little meat that was in the best health, so I doubt the vegetarians. I suspect ancient peoples ate lots of fish at first and then started eating lots of meat as they spread away from the coasts. My main evidence for the fish is my omega-3 results that imply our brains work best with lots of omega-3. My main evidence for the meat is the huge popularity among boys of video games that contain elements of hunting. It’s hardly great evidence, of course, since the popularity of those games, and of actual hunting, has other plausible explanations.
This is why my omega-3 self-experimentation interests me so much. It is a way to figure out the best diet for our brain. It relies on fast simple cheap easy-to-control experiments that anyone can do, rather than on epidemiology (correlations) or expensive slow hard-to-control clinical trials that often involve unusual people.
Perhaps warming food releases more flavor.
Fish aren’t the only rich source of long-chain omega-3 fats; our less squeamish paleolithic forebears could have obtained plentiful amounts from the brains of hunted or scavenged animals.
I believe that there are a number foods that are easier to digest, and a number that release nutrients when they are cooked. I can’t come up with good examples right now, how about consulting a nutritionist?
This sounds like a Quiznos ad.
This is an article copied from the September 13th edition of Nature (vol 449 pp. 155). I think you’d find it interesting.
EVOLUTIONARY GENETICS: You are what you ate
by Sadaf Shadan
It is hard to think of anyone who doesn’t like starchy foods such as pasta, chips, rice or bread. But certain populations, for example hunter—gatherers living in the rainforests or near the Arctic circle, have historically existed on a diet rich in protein and low in starch. George Perry and colleagues conclude that such differences in the amount of dietary starch have moulded the human genome over time (G. H. Perry et al. Nature Genet.
doi:10.1038/ng2123; 2007).
Dietary shifts — whether driven by the development of stone tools, by controlling fire or by domesticating plants and animals — have had a major role in human evolution. Perry and colleagues specifically looked at the effect of dietary starch on the number of copies of AMY1, the gene that encodes the salivary amylase enzyme, which breaks down starch. AMY1 is one of the few genes in the human genome that show extensive copy-number variation between individuals. So the authors first looked at whether additional AMY1 copies are functional. They found that extra AMY1 copies do indeed endow the individuals carrying them with the capacity to produce more salivary amylase. The question then was whether the starch content of
past diets dictates the present levels of amylase and, thus, AMY1 copy
number.
Perry et al. studied two groups: one consisted of four populations with a low-starch diet and the other of three populations from agricultural societies and hunter—gatherers in arid environments, who traditionally eat high-starch food. Strikingly, twice as many members of the high-starch-diet group had
at least six copies of AMY1. This difference could not be explained by geographical factors because both groups contained people of Asian and African origin. Instead, the authors propose that variations in AMY1 copy number are more likely to have been influenced by positive natural selection.
So what is the advantage of having more salivary amylase? Significant digestion of starch occurs during chewing. This is crucial, and probably vital, in people likely to suffer from diarrhoeal diseases. Moreover, after being swallowed,
salivary amylase is carried to the stomach and intestines, where it aids other digestive enzymes. Of the three copies of the AMY1 gene registered in the
reference sequence of the human genome, variations in nucleotide sequences are small. This suggests that the duplication of these genes may have occurred relatively recently, possibly even since the evolution of modern humans about 200,000 years ago. So Perry and colleagues’ results,
and elucidation of copy-number variations in other human genes, could provide insight into our ecological and evolutionary history.
I was wondering the same thing today. It just popped into my mind while microwaving some meat. Your idea of our ancestors eating freshly killed meat is interesting. It might be because we like food that matches our body temperature?
Or maybe it was a type of trial and error/natural selection thing – more people might have died from diseased meat (especially if it was scavenged) than cooked meat. So they learned, and kept cooking…
I was wondering about this over chicken pot pie. I think Larry’s hypothesis is interesting and makes sense. Our bodies want to get the most energy out of the food we eat, so the closer to our body temperature food is, the less energy is wasted by being lost to colder food.
We eat warm food for fetal comfort. Our mothers aminotic fluid temperature is about 37 degrees celcius. The human fetus can tatse and breathe the mothers amniotic fluid.
This is the primary reason we have to heat a newborn baby’ s bottle , a newborn will always refuse a cold bottle. We never lose our fetal knowledge
We discussed a similar topic in my Ancient Engineering course recently, and I came up with an answer to this question based on what we talked about (see below): It takes less energy to consume warm food. You chew less if the meat is tender, and it digests easier. From a thermodynamic standpoint, the molecules are moving around faster and therefore bonds are broken more easily.
In class we compared our gut size to an ape’s gut size (relative to the body). They have a much larger gut because they eat leaves. This requires a lot of chewing (hence larger teeth) and they get less energy per quantity. Therefore, they have to eat more, meaning a larger gut. Since a lot of the consumed energy goes towards digestion, their brains were not able to evolve like ours. We are able to allocate more energy to brain functions since we have a much better diet.
More about the relationship between diet, brain size, and gut size can be found at https://www.beyondveg.com/billings-t/comp-anat/comp-anat-4b.shtml
What I said is based on what I remember in class, but hopefully it is consistent with the article. I don’t think it mentions warm food, but I believe warm food falls under “better diet.”
I am researching natural health and wellbeing, hence my interest in why we eat warm food. Dans views of mechanical thermodynamics, are also important in biological thermodynamics. Basicly all life is exothermic(“cold blooded” but mammals, birds and some PLANTS have the ability to produce heat energy and are called endothermic life, (ie “warm blooded”).
Biologicaly we have got to remember that digestion is on a evolutionary point a chemical process that involves envolves enzymes and various raections.
Exothermic animals such as snakes, cocodiles, only have to eat once a month, or once every 2 years in the case of crocodiles, for nutrtion rather than for energy.
Carniverous plants also have enzymes, digesting captured animals and insects to provide valuble nutrtion rather than energy. Which brings me to the point that teeth evolved as a form of defense angainst predetors, canine teeth in humans are quite small but in chimps and gorillas they are extremely large for animals that are mainly plant eaters.
So my point is why do we like to eat warm food, or drink warm coffee or tea, or even take are warm bath, ( water drys your skin so moisturise before you have a bath and shower), and the answer is that are oxcytocin is realeased in our brain. Oxcytocin is the feel good chemical that gives us that comforting, and relaxying feeling
Sorry,i ended abruputl earlier, Oxcytocin is found in the mothers amniotic fluid, it also encourages the mothers brests to produce and realease Milk. ie lactation. So our brains are conditioned to experaiance warmth and comfort by the release of Oxcytocin.
I have discovered that mother nature does not create LIFE so it can be eaten as food souce, and that plants and animals dont exist so that they can taste good. I belive we have to learn to eat for nutrtion and health, and not for good tatse, it is unjustifiable to Mother nature that we kill and cause suffering to animals so that we can satisfy our taste buds.
You mentioned in the Original Post that you believe the fish diet to be the most compelling because of the high amount of Omega-3 present in fish. You are being partially misled by the way our present society works.
Omega-3 and Omega-6 are two major fatty acids that promote brain function. In many plants Omega-6 is found in the seed portion of the plant primarily, whereas Omega-3 is largely found in the plant body. We tend to lack Omega-3 because of the fact that we have moved to feeding our livestock (meat which previously would have had a better balance of Omega-3 and Omega-6) with corn (a seed, higher in omega-6). On top of that we are adding high fructose corn syrup, xanthan Gum, maltodextrin, citric acid, and many other products derrived from corn into our processed foods.
Some scientists (i’m not sure of the proportion) believe that its not just the lack of omega-3 in our diet that is the problem, but moreso that the imbalance is a problem.
With this in mind, i believe that ancient fish and ancient land-based wildlife were at least closer with each other with regards to omega-3 content, and that the mostly fish diet and the mostly meat diet are equally as valid.
Still want to know if easting warm food is better for you than lukewarm food