Tue Jul 15 03:00:00 UTC 2025: Okay, here’s a summary and rewritten news article, based on the provided text:

**Summary:**

A recent study published in *Nature* reveals that removing the non-essential amino acid cysteine from the diet of genetically modified mice (mice unable to produce cysteine naturally) led to a rapid 30% weight loss in one week. This effect wasn’t observed in normal mice. While the research is promising, it also showed potential side effects like increased oxidative stress, as cysteine is crucial for antioxidant production. Experts urge caution, emphasizing the differences between mouse and human physiology, and highlighting that the body will attempt to replenish cysteine levels even if restricted in the diet. Further research is needed before these findings can be translated into human applications. The original work on essential amino acids by William Rose in 1937 helped lay the ground work for this study.

**News Article:**

**Cysteine Restriction Leads to Rapid Weight Loss in Mice, Human Application Still Far Off**

**CHENNAI, July 15, 2025** – In a surprising discovery, researchers have found that restricting the amino acid cysteine in genetically modified mice leads to a dramatic and rapid weight loss. The study, published in *Nature*, revealed that mice unable to produce cysteine naturally lost an average of 30% of their body weight in just one week when cysteine was removed from their diet.

The findings build upon decades of research into the role of amino acids in nutrition, dating back to William Rose’s groundbreaking work in the 1930s on essential amino acids. Prior studies had explored the effects of restricting *essential* amino acids on weight loss, however this study focused on Cysteine, a non-essential amino acid.

While the weight loss effect was significant, researchers also noted an increase in oxidative stress, a potentially harmful condition, due to cysteine’s role in producing the antioxidant glutathione.

Experts are urging caution in interpreting the results, particularly in the context of human health. “Firstly, if you remove [cysteine], the body is going to anyway replenish it,” said Dr. Jayashree Gopal, consultant endocrinologist at DiabEndoIndia in Chennai. “Secondly, because it is part of a very potent antioxidant system, we should not be interfering with nature’s balances until we know more about it. And third, we have to keep reiterating that the study is only done in genetically modified mice. Mouse physiology and human physiology are very, very different.”

Dr. Gopal noted that the conversion of white fat to brown fat was a marker for improved metabolic activity in the study.

According to Arun Panchapakesan, assistant professor at the Y.R. Gaitonde Centre for AIDS Research and Education, Chennai, the study highlights the complexity of nutritional science and that it may take years for results to be translated to humans.

The findings offer a potential avenue for future research into weight management, but scientists emphasize that further studies are necessary to fully understand the long-term effects and safety of cysteine restriction in humans. This breakthrough highlights the promise of future applications in combating obesity and metabolic diseases, while underlining the need for meticulous research and careful considerations for human physiology.

**Note:** I’ve tried to maintain a neutral tone befitting a news article. I’ve also included quotes from the expert to add credibility and a balanced perspective.

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