Submitted by Amy Sercel MS RD CD
Edited by Marcia Bristow MS RDN CSSD CD
From sugar-free candy to diet soda, artificial
sweeteners are everywhere. Whether
you’re trying to limit your sugar intake to lose weight, you have diabetes, or are
working to promote your overall health, you might choose foods made with
artificial sweeteners because they contain fewer calories than foods made with
sugar. Unfortunately, recent studies
have shown that consuming artificial sweeteners may not actually be as health
promoting as you might think.
When you eat sugar, a pathway in your brain
is activated that ultimately causes the release of dopamine, a neurotransmitter
that signals pleasure. Dopamine is
considered an essential part of the reward pathway in the brain, and it’s part
of the reason that sugary foods taste so good to people. Your brain releases dopamine when you take
the first bite of something sweet, but as you continue eating it your body
releases other hormones to signal that you aren’t hungry anymore.1,2
Recently, researchers have investigated how
artificial sweeteners, which taste sweet but do not provide your body with any
calories, might impact this reward pathway.
It appears that the reward pathway is only fully activated when a sweet
taste is accompanied by calories.2–4 Researchers found that hungry mice consistently chose food that
contained real sugar, and therefore also contained calories, instead of the artificially
sweetened food. They believe this is
because the hormones signaling that you are no longer hungry are only released
when the sugar in the sweet food you eat is converted into glucose for your
cells to use as fuel.2
If you regularly consume artificial
sweeteners, it appears that the reward pathway in your brain could be thrown
off so food that contains real sugar will become even more rewarding, making
you want to eat more in general.5,6 This may explain why people who consume more artificial
sweeteners tend to have a higher body mass index, and people do not tend to
lose much weight by switching from caloric to artificial sweeteners. The pleasant taste of the artificial
sweeteners activates the dopamine reward pathway, but because that taste is not
accompanied by calories the pathway is not turned off. As a result, you will continue to look for
food until you’ve satisfied your body’s need for calories.7
Research in this area is still evolving, so
it will be important to continue learning about new findings related to the
influence of artificial sweeteners’ on the brain’s reward pathway. In the meantime, limit the amount of
artificial sweeteners you consume. Choose
whole, unprocessed foods whenever possible.
If you’re a diet soda-drinker, consider switching to unsweetened iced
tea or sparkling water flavored with a splash of fruit juice or infused with
some fresh fruit. This will help you
stay hydrated and you might find that you have more energy as a result. If you’re craving a sweet snack, try some
fresh fruit with nut butter, a handful of trail mix that contains raisins or
other dried fruit, or some yogurt with a little granola. These foods will satisfy your craving while
providing other important nutrients, making them great options for anyone
looking to manage their weight and promote overall health.
References:
1. Murray S, Tulloch A, Criscitelli K,
Avena NM. Recent studies of the effects of sugars on brain systems involved in
energy balance and reward: Relevance to low calorie sweeteners. Physiol
Behav. 2016;164:504-508. doi:10.1016/j.physbeh.2016.04.004
2. Kirkwood C,
Kirkwood C. Tricking Taste Buds but Not the Brain: Artificial Sweeteners Change
Brain’s Pleasure Response to Sweet. Scientific American Blog Network.
https://blogs.scientificamerican.com/mind-guest-blog/tricking-taste-buds-but-not-the-brain-artificial-sweeteners-change-braine28099s-pleasure-response-to-sweet/.
Accessed February 26, 2018.
3. Brain cannot be
fooled by artificial sweeteners; higher likelihood of sugar consumption later
-- ScienceDaily.
https://www.sciencedaily.com/releases/2013/09/130922205933.htm. Accessed
February 27, 2018.
4. Tellez LA, Ren X,
Han W, et al. Glucose utilization rates regulate intake levels of artificial
sweeteners. J Physiol. 2013;591(22):5727-5744. doi:10.1113/jphysiol.2013.263103
5. Green E, Murphy C.
Altered processing of sweet taste in the brain of diet soda drinkers. Physiol
Behav. 2012;107(4):560-567. doi:10.1016/j.physbeh.2012.05.006
6. Why artificial
sweeteners can increase appetite -- ScienceDaily. https://www.sciencedaily.com/releases/2016/07/160712130107.htm.
Accessed February 27, 2018.
7. Yang Q. Gain
weight by “going diet?” Artificial sweeteners and the neurobiology of sugar
cravings. Yale J Biol Med. 2010;83:101-108.
