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title: This New Drug Turns &#x27;Bad&#x27; White Fat Into &#x27;Good&#x27; Brown Fat
description: Scientists claim they have found an experimental drug that turns “bad” white-fat cells into “good” brown ones.
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author: Helen Regan
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article:published_time: 2015-03-09T08:13:25.000Z
article:modified_time: 2026-02-22T05:00:24.447Z
article:section: Health
og:title: New Drug Turns &#x27;Bad&#x27; White Fat Into &#x27;Good&#x27; Brown Fat
og:description: Researchers found the drug caused weight loss in obese mice.
og:url: https://time.com/3736916/white-brown-fat-weight-loss-study-gc-1/
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twitter:title: New Drug Turns &#x27;Bad&#x27; White Fat Into &#x27;Good&#x27; Brown Fat
twitter:description: Researchers found the drug caused weight loss in obese mice.
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# This New Drug Turns 'Bad' White Fat Into 'Good' Brown Fat

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by 

[Helen Regan](https://time.com/author/helen-regan/)


## Helen Regan


Mar 9, 2015 8:13 AM UTC

by 

[Helen Regan](https://time.com/author/helen-regan/)


## Helen Regan


Mar 9, 2015 8:13 AM UTC

Scientists claim they have found an [experimental](http://www.sciencedaily.com/releases/2015/03/150307095940.htm) drug that turns “bad” white fat cells into “good” brown ones.

Known as GC-1, the drug speeds up metabolism, or the burning off of fat cells, reports Science Daily. Researchers found it caused weight loss in fat mice.

“GC-1 dramatically increases the metabolic rate, essentially converting white fat, which stores excess calories and is associated with obesity and metabolic disease, into a fat like calorie-burning brown fat,” said study author Kevin Phillips of the Houston Methodist Research Institute.

Until recently, scientists thought only animals and human infants had these energy-burning “good” [brown-fat](http://www.webmd.com/diet/20141022/brown-fat-weight-loss) cells.

“It is now clear that human adults do have brown fat, but appear to lose its calorie-burning activity over time,” Phillips added.

He calls white fat a “metabolic villain” when you have too much of it, whereas people with more brown fat have a reduced risk of obesity and diabetes.

GC-1 works by activating receptors for the thyroid hormone, which help regulate how your body turns food into energy.

Phillips’ team tested the drug on hundreds of mice who were genetically obese or who had diet-induced obesity. They found genetically obese mice lost weight and nearly 50% of their fat mass in two weeks. Diet-induced obese mice also showed improvements.

The drug was also tested on white fat cells grown in a lab, and researchers say they found evidence that the drug turned white fat into the brown variety.


Phillips hopes the drug, which has not yet been tested on humans, has the potential to treat obesity and metabolic disease.

The results of the study will be presented at the Endocrine Society’s 97th annual meeting in San Diego on Friday.

\[[_Science Daily_](http://www.sciencedaily.com/releases/2015/03/150307095940.htm)\]

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