Foods that cool? I’m not talking about ice cream.
There are two different strategies – a long term and a short term solution, if you will – you can employ to keep yourself cooler than the average person this summer.
First, Let’s talk short term.
Your body temperature is always in the process of spreading across all of your body’s mass, including what’s inside of you but not actually part of your body. When you consume something that’s warmer than your body, such as a hot beverage, that temperature “leaks out,” into the rest of your body; the liquid cools as your body temperature rises slightly. This only lasts a short while because your body is always striving to maintain homeostasis.
Similarly, if you eat something cold, your overall body temperature will temporarily dip until your body can return to homeostasis.
In an experiment having people ingest 500 grams of ice cream, for instance, body temperture fell 0.8 ºC1
But some cold foods create far more of a cooling effect than others.
Water-based foods are among the most effective at cooling you down, since most liquids are better at heat transfer than solids. Liquid is around 15ºC cooler than your body at room temperature, but if the the food has been sitting in the fridge for a few hours and is thoroughly cold, the effect will be all the more drastic.
Foods That Cool: Enter The Watermelon
In all my experimentation, nothing has proven a more effective cooler – including just straight up drinking ice water – than simply eating a large meal of delicious cold watermelon.
Even other high-water-content melons such as cantaloupe fail to bring about as much of a dip in body temperature, nor one that lasts so long.
So if you want to feel significantly cooler for an hour or more, eat half of a chilled watermelon (let it sit in the fridge for three or four hours) for breakfast or lunch. Remember that watermelon is very calorically diluted by its water content, so you don’t really have to worry about overeating. Filling up your stomach with it is important to feel the full effect, so eat it for the entire meal.
How effective is this?
For me, sitting in shorts and a teeshirt in an 80ºF room is usually comfortable. But after eating half of a chilled watermelon, I’m comfortable but pushing towards too cool. I almost feel like I need another layer, particularly if there’s a breeze.
I find this cooling maxes out about five to 10 minutes post meal. Your body temperature will rise back up over the course of a little more than an hour if you’re relatively sedentary, or more quickly if you’re physically active.
Cooling Foods: The Long Term Approach
Across mammalian species, researchers have noted a correlation; animals with cooler body temperatures live longer. In human studies, those with lower body temperatures have better survival rates and live longer lifespans 2
Although genetics influences our body temperature, it is malleable. Caloric restriction is known to reduce body temperature in humans and other mammals, for instance, and is also correlated with increased lifespans 3.
No one has studied long term adherents to healthy fruit-based, low fat raw food diets, but they should. In particular, observing adherents body temperature would be very interesting. While normal, body temperature is considered 97.7 – 99.5 °F, my own tends to range between 96.8 and 97.2 °F while adhering to a raw food diet, but in the “normal” range when eating cooked foods.
While a raw-food-based dip in temperature may or may not end up being correlated with longer lifespan, it definitely does make heat considerably more bearable. I find that temperatures that bother most people feel just fine to me, and that a raw diet make the hot summers of Austin, Texas a lot more enjoyable.
So if you want to feel cooler in the heat this summer, try sticking to an all-raw diet for two weeks and see how it affects your body temperature.
To learn how to eat a healthy raw food diet that will improve your health, help you lose weight, and keep you cool, check out Raw Food Weight Loss And Vitality.
Eccles, R. Cold pleasure. Why we like ice drinks, ice-lollies and ice cream. Appetite 71 (2013) 357–360↩
Keil, Gerald. Et al. “Being Cool: How Body Temperature Influences Ageing and Longevity.” Biogerontology 16.4 (2015): 383–397. PMC.↩
Kelly GS (March 2007). “Body temperature variability (Part 2): masking influences of body temperature variability and a review of body temperature variability in disease”. Altern Med Rev. 12 (1): 49–62↩