Recently Rob and I were sitting at a durian stall, contentedly licking our fingers after a pretty epic durian meal.
We were feeling satiated and content, but the ladies who’d watched us eat were worried. They pursed their lips, shook their heads, and thrust durian shells full of water at us.
“They’re worried about you eating so much durian,” a man said. “Don’t you feel hot?”
It wasn’t the first time a well-meaning local warned me that eating too much durian would not only make me feel uncomfortably warm, but could actually be dangerous to my health due to it’s “heaty” properties.
The handful of deaths that occur every year after durian consumption, with or without alcohol, are often attributed to this “heatiness”, sometimes blamed on the the fruit’s high caloric density, or its high-ish fat content, or its sugar load.
The “heaty” phenomenon has so profoundly effected the culture of eating durian that in many places in Asia you can’t even buy durian until late afternoon or evening, when the air is cooler and the danger of overeating is lessened.
But does durian really make you feel hot? Or is it just really hot in Southeast Asia to start with?
Here’s a what the latest research says about whether or not durian is “heaty.”
What is Heaty?
The term heaty used to drive my grammar obsessive husband a little wild, because heaty is not actually a word in English.
But it’s the word somebody a long time ago chose to translate the Chinese term Shanghuo (上火) , which in Traditional Chinese Medicine describes an imbalance in the body of yang energy and translates loosely as “internal heat.”
Shanghuo might cause a person to feel uncomfortably hot, sweat profusely, and have headaches, fever, sore throat, or rashes.
To prevent these uncomfortable symptoms, heaty foods like durian need to be balanced by consuming something with yin or “cooling” properties – like mangosteen, coconut water, or tea.
Some classifications seem intuitive. Along with durian, spices like garlic, ginger, and chili peppers are heaty. Others seem more random.
For example, mangoes are heaty, yet bananas are cooling.
Beer is cooling too.
If the classifying characteristics of heating or cooling foods follow rules, I don’t understand what those rules are.
But that doesn’t mean there isn’t something chemically magical about durian that raises body temperature. These studies almost (but not quite) prove that heatiness is real.
Hyperthermic Effects Of Durian
Hyperthermia is the medical term for abnormally high body temperature. It’s the opposite of hypothermia, and equally as dangerous.
The first study ever done on the hyperthermic effects of durian was published in 2008 from the University in Kelantan, Malaysia.
The title is fairly self-explanatory: Hyperthermic Effects of Durio zibethinus and its Interaction with Paracetamol.
That is if you’ve heard of paracetamol. Which I hadn’t, because in America we call it aspirin (Edit: readers have informed me that actually paracetamol is actually what we call Tylenol. Not aspirin).
Fever-reducing drugs with durian? Interesting idea.
Aspirin is often used to reduce fevers, which raises an interesting question.
Could fever-reducing drugs be used to stymie the (assumed) thermal discomfort of durian revelers?
Not if local lore is to be believed. Similar to the durian+alcohol=death story, apparently many Malaysians believe that combining durian with aspirin is also toxic.
The study hoped to kill two myths with one set of research rats: find out whether or not durian raises body temperature, and see if using a fever reducer to combat possible hyperthermia would permanently damage your liver.
Researchers fed five groups of mice combinations of Chanee durian, aspirin/paracetamol, and another drug known to lower blood pressure and measured their temperatures over the course of one hour.
I felt sorry for the control group, who did not get to have any durian but who still had to have a thermometer stuck up their butts multiple times in an hour.
The results were surprising.
Group 4 , who ate a combination of durian and aspirin, experienced the lowest body temperature.
Their temperature was even lower than mice given plain aspirin (Group 3).
Chua and co. decided that this bizarre drop in body temperature might be causing the effect people associate with toxicity. Unfortunately, they didn’t comment on whether or not popping a painkiller with durian actually results in liver poisoning.
That’s sort of interesting, but the more exciting result is from Group 2, the group that ate only durian.
|Group 1: Water only Group 2: Durian only Group 3: Paracetamol
Durian raised their body temperature. For realz.
It’s so slight it’s difficult to see on the graph, a temperature change measuring only 1 F which returned to normal within one hour.
The researchers concluded the temperature difference was so insignificant that the mice were unlikely to be experiencing the uncomfortable symptoms associated with “heatiness.”
This is the only study that has ever shown scientific evidence of durian causing elevated body temperature.
Even this next study, a technically highfalutin’ piece of research from Japan, didn’t prove that durian raises body temperature.
They just assumed that it does, and tried to figure out why.
Durian and Sulphur
To get through this next study, you need a high tolerance for confusing words and technical acronyms. The title alone had me fleeing to Wikipedia.
The study, “Sulphur-containing compounds of durian activated thermogenesis-inducing receptors TRPA1 and TRPV1,” comes from the University of Tsukuba and is every bit as technical and impressive as their work with alcohol and durian.
In Japan they do the like sciencey type science.
TRPA1 and TRPV1 are the lovely names of different Transient Receptor Potentials (TRP), which sounds to me like equipment on the Star Trek Enterprise.
In reality they’re responsible for the pain we associate with chili peppers, the cool breath advertised by mint chewing gums, and the nasal-clearing, eye-watering burn of wasabi (I adore this effect, and if we ever go out to Sushi together I will smile maniacally through the tears).
The researchers noted:
“In Traditional Chinese Medicine, spices containing TRPA1 and TRPV1 agonists (e.g. hot pepper, mustard, cinnamon, garlic, and pepper) are classified as foods of body-warming nature.”
They hypothesized that sulfur compounds in durian are similar enough to to the ones found in garlic that they might be stimulating either TRPA1 or TRPV1, resulting in the sensation of heat and the association with “heatiness.”
Sounds plausible to me.
To test their hypothesis, the researchers purchased 3 fresh Malaysian D24 from a market in Singapore. It’s unclear how they got the fruits to Japan, but by the time of the experiment the fruits were splitting and were probably overripe.
They then extracted five sulfur containing compounds from the durian and tested them on the two TRPs mentioned in the title, a process that took two pages of Greek symbols and acronyms to explain.
I’ll be honest – I skimmed. Until I got to the summary:
Comparing these data in Table 1, each of the disulphides and trisulphides contained in durian and garlic have nearly equal potency against these two TRP channels.
So yes, the sulphurous compounds in durian activated the TRP channels, particularly TRPA1, in a way nearly identical to garlic.
So that validates the media’s fixation on comparing durian with garlic. Apparently, they smell alike for a reason.
But that raised another question for me.
Is it an illusion of heat, or is it real?
I know that chilies can make you feel like your tongue has just been pressed to the wrong side of a hot iron, when in reality the skin tissue is undamaged. It’s just chemical trick caused by those dastardly TRP channels.
So what about body temperature? Real, or illusion?
Apparently the chilies and garlic really do raise your body temperature. The “dangerous, fever-like rise in body temperature” from eating chilies has been an annoyance to researchers trying to figure out how to utilize that same TRPVA1 receptor for pain relief.
Is Heatiness Real? The Conclusion
Despite the seemingly medieval rationale behind “heaty” and “cooling” foods, I don’t think the concept will be going the way of the Four Humors and bloodletting any time soon.
It’s clear that some foods have the ability to raise our core body temperatures through complex chemical reactions.
Preliminary research shows that durian also has temperature-raising capacities, although it’s not clear how significantly. The study measuring body temperature in mice found that durian caused a 1 F increase that normalized after only one hour. That’s hardly a sore throats, rashes, and sleepless nights attributed to shanghuo.
Regardless, durian’s “heaty” quality isn’t caused by fat, caloric density, or sugar content. It’s a chemical reaction with our biology, which means that it’s possible the degree of heat and discomfort experienced might even be genetic, the way that mixing durian and alcohol is probably more of a problem for Asian people than for Westerners.
Which might explain why personally, I don’t care what time of day I eat durian. I’m never too hot for durian.
What you can do
So far, no one has done the simple test of measuring human body temperatures before and after eating durian. Yet it’s a simple thing that anyone can do.
So here is my challenge to you:
Wherever you are in the world, find a thermometer. Eat some durian. Measure your temperature before and after.
Write it down, and post your results and the type of durian you were eating in the comments below.
If the sciencey-type scientists aren’t going to take responsibility to find out if durian is really “heaty” or not, I say it’s up to us durian lovers to find out for ourselves.
Who knows, we might prevent the next durian death.
Links to the two studies:
- Chua, YA. Hyperthermic Effects of Durio zibethinus and its Interaction with Paracetamol. Methods Find Exp Clin Pharmacol 30 (2008).
- Terada, Yuko. “Sulphur-containing compounds of durian activated thermogenesis-inducing receptors TRPA1 and TRPV1.” Food Chemistry (2014).