Two totally different mind circuits assist regulate salt consumption, in line with a research within the journal Cell. One adjusts salt cravings, the opposite determines whether or not we discover salty meals scrumptious or disgusting.
ARI SHAPIRO, HOST:
Meals and drinks which can be actually salty might be interesting someday and off-putting the subsequent. Now scientists assume they know why. NPR’s Jon Hamilton studies on a research that discovered two separate mind circuits that affect our style for salt.
JON HAMILTON, BYLINE: Our relationship with salt is sophisticated. Yuki Oka, a scientist at Caltech, says sodas, sports activities drinks and even faucet water all comprise a bit of salt, also called sodium chloride.
YUKI OKA: You get pleasure from low sodium water, however when you think about very excessive focus of sodium like ocean water, you actually hate it.
HAMILTON: Until your physique is actually low on salt. That is fairly uncommon in individuals as of late. However Oka says experiments with animals present that when salt ranges plummet, the tolerance for salty water goes up.
OKA: In case your physique wants sodium, then animals instantly begin liking ocean water.
HAMILTON: They crave sodium, and so they can tolerate it in excessive concentrations they’d usually keep away from. Oka needed to know the way this technique works within the mind, so he and a workforce of scientists studied mice. They confirmed that one set of neurons towards the again of the mind regulates the yearning for salt.
OKA: When you stimulate these neurons, then animals run to sodium supply after which begin consuming.
HAMILTON: One other group of neurons towards the entrance of the mind usually units an higher restrict on salt tolerance, however when salt ranges get low sufficient, Oka says, these neurons get switched off.
OKA: Which means that the sodium craving and the sodium tolerance are managed by fully several types of neurons.
HAMILTON: The discovering, which seems within the journal Cell, is a part of a rising discipline of research referred to as interoception. It offers with inside sensations like starvation and ache. Stephen Liberles, a cell biologist at Harvard Medical College, says scientists already know quite a bit about how the mind offers with sensory info coming from the eyes, ears, nostril and pores and skin.
STEPHEN LIBERLES: The mind additionally receives tons of sensory info from the physique, from the guts, the lungs, the abdomen, the gut, and the way these work has remained extra mysterious.
HAMILTON: The brand new research means that mind cells concerned in salt tolerance are managed by hormone-like substances referred to as prostaglandins. These substances, which flow into within the bloodstream, are greatest recognized for his or her function in inflicting irritation, fever and ache. Liberles says it now seems that prostaglandins additionally play a task in salt tolerance.
LIBERLES: So the query is, how is similar chemical, the identical prostaglandin molecule re-used throughout organic techniques in several contexts?
HAMILTON: Answering that query may make it attainable to develop a prostaglandin drug to discourage salt overconsumption. Nirupa Chaudhari of the College of Miami says we are likely to eat an excessive amount of salt as a result of evolution ready our our bodies for a world by which salt is scarce.
NIRUPA CHAUDHARI: Wars have been fought over salt just some centuries in the past. So we consider sodium chloride – desk salt – as so plentiful in our weight loss program and in the environment however it wasn’t at all times.
HAMILTON: Chaudhari says an excessive amount of salt can result in hypertension and coronary heart illness.
CHAUDHARI: Salt ingestion is a significant subject. Calorie ingestion is a significant subject. So it turns into actually essential to know how all of those totally different techniques work.
HAMILTON: She says understanding how the mind processes saltiness may assist meals firms develop a palatable salt substitute. Not less than one earlier effort failed badly.
CHAUDHARI: It tasted actually foul, so individuals did not wish to use it.
HAMILTON: Chaudhari says discovering a greater choice could require extra analysis on not solely how the mind displays salt consumption however the way it interacts with our style buds. Jon Hamilton, NPR Information.
Copyright © 2023 NPR. All rights reserved. Go to our web site phrases of use and permissions pages at www.npr.org for additional info.
NPR transcripts are created on a rush deadline by an NPR contractor. This textual content is probably not in its last kind and could also be up to date or revised sooner or later. Accuracy and availability could range. The authoritative document of NPR’s programming is the audio document.
