Don't forget to protect your pets from the heat
As we face increasingly hot summers, understanding how to avoid the health dangers associated with high temperatures has become more important than ever. Here are some tips to help you stay cool in scorching weather.
1. Stay hydrated
Water
is vital to keep you both healthy and cool. When you are dehydrated,[1] the amount of blood flowing through your
cardiovascular system decreases, which makes your heart work harder, increasing
your core body temperature. On a regular day, most healthy adults need between
1/2 and 3/4 of a gallon (2-3 liters) of water. In hot weather, you’ll need to
drink more than you usually would. You should start with plain water and switch
to drinks containing electrolytes like coconut water[2] and Gatorade later in the day to replenish
the ones you’ve sweated out. If you fancy something colder, flavored ice cubes
from fruit and herbs[3] or juices[4] will both add pizzazz to your drink and
replenish your electrolytes.[5]
Hot drinks can also cool you down if you are already feeling hot. This may seem counterintuitive, and indeed, they will initially make you feel hotter, but that will make you sweat, which will lower your body temperature.[6] There’s just one caveat: the sweat needs to be able to evaporate quickly,[7] so this trick will not work if hot temperatures are paired with high humidity, or if you’re wearing a lot of clothing. Avoid caffeine, which causes vasoconstriction,[8] the constriction of blood vessels that warms the body. Trying to cool down with an iced coffee or an energy drink may temporarily cool you, but then the warming effect of caffeine will kick in. Finally, ditch the booze: alcohol is a diuretic[9] that causes you to urinate more and can leave you severely dehydrated.
2. Eat wisely
Eating
can increase your core temperature as your body works to digest and metabolize
your meal.[10] The more calories you eat, the hotter your
body will get. Therefore, try to eat light; salads will keep you cooler and
also have the benefit of not requiring you to slave over a hot stove to make
them. Salads also often contain foods that have a high water content,[11] like cucumber, lettuce, and tomatoes. These
foods both replenish your electrolytes and help you stay hydrated.
If
you’re thinking that you would prefer your cold food in the form of ice cream,
think again. Sadly, eating this frozen treat may actually make you hotter as
your body works to digest the calories. Sorbets[12] are a
better alternative. At the other end of the flavor scale, spicy foods,[13] like hot drinks, also cool us down. This is
because spicy foods excite thermoreceptors in the skin that normally respond to
heat, triggering the usual responses — vasodilation, flushing, and sweating —
which help you cool off. Spices can also curb your appetite[14] and help you to eat lighter meals.
3. Use a fan — sometimes
Fans
cool us down by speeding up the evaporation of sweat from our bodies, but they
do not work equally well in all situations. Fans can actually make you feel
worse in dry heat. Sweat evaporates without any extra help when it’s very hot
and dry, so, under those conditions, fans merely blow suffocating air around
the room, creating an environment similar to a convection oven and causing you
to dehydrate. And the fan’s motor can make the room even hotter. Both the U.S.
Environmental Protection Agency[15] and the
World Health Organization[16] advise
against using fans in temperatures above the mid to high 90sºF (above 35ºC).
However,
a 2019 study[17] found that fans do provide relief when
conditions are humid. You can enhance the cooling feeling by misting your body
with water or by putting a preferably metal or glass bowl of ice cubes in front
of the fan.[18]
4. Be clever with water
Water
is not just for drinking; it can provide relief from the heat in other ways.[19] There are four major areas on your body where
large blood vessels lie close to the skin surface: the neck, each of the
armpits, and the groin area. Putting a cold, wet cloth or an ice pack in those
areas will quickly cool you down; it’s what emergency room doctors do to help
victims of heatstroke.[20] Even
room-temperature water on the back of your neck is better than nothing.
A
2015 study[21] found that applying cold packs to the
cheeks, palms, and soles of the feet — which have blood vessels that don’t
contract when cold packs are applied — is also effective. Another good way to
cool down is to put your hands, which have a high surface area-to-volume ratio,
predisposing them to heat loss, and feet in cold water.[22] It can also reduce swelling. Finally, a
lukewarm bath,[23] with water at 90ºF (27ºC),
has been shown to be one of the most effective methods of cooling.
Whatever
you do, don’t jump into a cold body of water like a deep lake, no matter how
inviting it may look, because sudden immersion in cold water — which can be as
warm as 77ºF/25ºC[24] — can cause a “cold
shock” response, which includes an involuntary gasp reflex followed by
uncontrollable hyperventilation, both of which will cause you to take water
into your lungs and drown.
5. Dress for the heat
In
hot weather, choose clothes that are light-colored — because they absorb less
of the sun’s radiation than darker clothing — and lightweight. Materials that
“breathe” and allow air to flow through the fabric keep you cool by allowing
air to circulate without getting trapped, letting it flow past your skin and
carry the warmth away from your body while cooler air flows in behind it.
Fabrics[25] like cotton and linen are among the most
breathable, and high-tech sportswear made from “moisture wicking” fabrics will
transport sweat away from your skin to the outer layers of the material, where
it can evaporate.
6. Wear sunscreen
Sunburn
limits the body’s ability to get rid of heat by compromising skin circulation
and sweating. Ultraviolet radiation absorbed by the skin can also damage
genetic material and increase the risk of cancer. Experts[26] recommend using a broad-spectrum sunscreen
lotion that has a sun protection factor (SPF) of at least 15. You should smear
it on about 20 minutes before you go out in the sun. This is because sunscreens
are usually emulsion formulas[27] that
need to dry and physically bind to skin to form a film. Early application
prevents you from immediately brushing or sweating the sunscreen off.
According
to a 2012 review,[28] sunscreen is especially
important between 10 a.m. and 2 p.m. That said, if you can, it’s best to avoid
going outside when the sun is at its strongest, usually between 10 a.m. and 4
p.m. in the Northern Hemisphere. When you do go out, consider wearing a hat,
sunglasses, and protective clothing.
7. Activate your pressure points
Acupressure
is a traditional Chinese medicine therapy that involves improving energy flow —
qi or chi — by applying pressure to key points on the body. It’s like
acupuncture, except that it uses manual pressure — from a thumb, finger, or
knuckle — instead of needles. Pressure is applied gently and firmly for up to
three minutes per pressure point. Pressure points located[29] on your hand (Li 4, Ht 8) and near your
elbow (PC 3, Li 11) may assist in cooling you down.
8. Roll your tongue and breathe
Yoga
experts swear by a technique called shitali pranayama, which is supposed to
have a cooling effect on your body and your mind.
To
do the cooling breath (shitali):[30]
- Sit in a comfortable seated position. Close your eyes
and relax your body.
- Stick out your tongue and roll the sides in a U shape.
(If you can’t do this, purse your lips and make a small ‘o’ shape with the
mouth.)
- Slowly inhale through your tongue in this tube
position.
- Then close your mouth and exhale out through your nose.
- Repeat it 5-8 times, which should just take about 5
minutes.
You
should experience a feeling of coldness on your tongue and the roof of your
mouth. With practice, you should be able to increase the duration of the
inhalation and increase the cooling effect
9. Keep vigorous exercise to a minimum
Exercising
in extreme heat puts extra stress on your body.[31] In order
to cool itself down, your body sends more blood to the surface to circulate
through your skin. This leaves your muscles with less blood, which, in turn,
causes your heart rate to increase. High humidity aggravates the situation by
not allowing the sweat to evaporate readily from your skin, which pushes your
body temperature even higher. This can lead to cramps, fainting, or, in the
worse cases, heat exhaustion then heatstroke. Better to just give yourself the
day off.
10. Seek out green spaces
Trees
and plants absorb water through their roots and transpire it out of their
leaves. This makes their immediate surroundings cooler as the heat from the surrounding
air is used to help the water evaporate. Trees also provide cooling shade.
During the summer, only 10% to 30% of the sun’s energy reaches the ground below
the tree. The rest is either absorbed and used for photosynthesis by
the leaves in the canopy, or reflected back into the atmosphere. Research[32] has found that suburban areas with mature
trees can be 4 to 6ºF (2 to 3ºC) cooler than suburbs without trees.
References:
- completeptlincoln.com/cpt-benefits-of-staying-hydrated/
- doi.org/10.2114/jpa.21.93
- fruitsandveggies.org/recipes/flavored-ice-cubes/
- theharvestkitchen.com/immune-boosting-flavored-ice-cubes/
- womensrunning.com/health/food/electrolyte-rich-fruits-summer-hydration/
- healthyliving.azcentral.com/evaporating-sweat-cool-down-9657.html
- doi.org/10.1111/j.1748-1716.2012.02452.x
- doi.org/10.1177/0748730414523078
- drinkhydrant.com/blogs/news/does-alcohol-dehydrate-you
- ncbi.nlm.nih.gov/books/NBK236229/#_ddd00166_
- healthline.com/nutrition/19-hydrating-foods
- asweetpeachef.com/easy-fruit-sorbet-recipes/
- www.sbs.com.au/topics/science/humans/article/2016/11/18/how-hot-food-can-cool-you-down-summer
- doi.org/10.1016/j.physbeh.2010.11.018
- epa.gov/sites/default/files/2016-03/documents/eheguide_final.pdf
- who.int/news-room/fact-sheets/detail/climate-change-heat-and-health
- doi.org/10.7326/M19-0512
- apartmenttherapy.com/beating-the-heat-with-low-tech-122423
- www.eurekalert.org/multimedia/796995
- newsnetwork.mayoclinic.org/discussion/keeping-cool-in-blistering-hot-weather/
- doi.org/10.1016/j.wem.2014.11.006
- doi.org/10.1016/S1440-2440(01)80026-8
- ncbi.nlm.nih.gov/books/NBK459311/
- en.wikipedia.org/wiki/Cold_shock_response#Water_temperature
- stitchfix.com/women/blog/fashion-tips/guide-breathable-summer-fabrics/
- fda.gov/consumers/consumer-updates/tips-stay-safe-sun-sunscreen-sunglasses
- labmuffin.com/need-apply-sunscreen-sun-exposure/
- ncbi.nlm.nih.gov/pmc/articles/PMC3460660/
- tcmtips.com/how-to-reduce-body-heat-by-acupressure/
- yogalily.com/shitali-pranayama-cooling-breath/
- mayoclinic.org/healthy-lifestyle/fitness/in-depth/exercise/art-20048167
- doi.org/10.2172/10180633