Gold proved more effective than specialized medications in combating obesity.

Excess weight is a significant issue in many countries. According to the World Health Organization, over 16% of the adult population globally is classified as overweight. These individuals are at a higher risk for type 2 diabetes, cardiovascular diseases, and other health issues. Finding effective methods to combat obesity is crucial to alleviate the burden on healthcare systems.

A widely used treatment for excess weight is "Ozempic," but despite its effectiveness, it comes with serious side effects. Notably, it reduces both fat and muscle mass evenly. Given that modern individuals already have significantly lower muscle mass than is natural, this poses health risks: muscles are responsible for producing essential compounds for the body, called myokines, which are necessary for optimal functioning.

Another popular medication is "Orlistat," which reduces weight by no more than 6%. The weight loss is entirely attributed to fat tissue rather than muscle. It works by blocking a specific enzyme—lipase—that is responsible for breaking down fats in the intestine. Consequently, fats are not absorbed into the bloodstream and are expelled from the body, resulting in weight loss. However, this medication has significant drawbacks, including side effects like diarrhea and abdominal pain, and prolonged use may negatively affect the liver.

Researchers continue to actively search for a weight-loss solution that does not affect the already deficient muscle tissue, focusing solely on reducing fat volume.

Scientists from Alexandria University in Egypt decided to investigate gold nanoparticles, which are microscopic gold particles known for their chemical inertness and their ability to easily penetrate cells and tissues, including adipose tissue. Experts hypothesized that gold nanoparticles could activate fat breakdown processes in adipose tissue and reduce the accumulation of harmful substances associated with obesity. To test this hypothesis, an experiment was conducted on laboratory rats.

All the rodents were divided into six groups. The control group received a regular healthy diet and did not undergo any treatment. The obesity group was fed a high-fat diet that mimicked human obesity, also without treatment. The remaining groups were administered gold nanoparticles in varying dosages (considered high at 52.33 micrograms per kilogram and low at 5.21 micrograms per kilogram). The last group was given "Orlistat." Gold nanoparticles and "Orlistat" were administered to the rats intramuscularly.

The experiment lasted nine weeks. Following this period, the researchers measured the rats' weight, their fat and muscle mass, and assessed their blood condition. Additionally, they examined the primary internal organ affected by obesity—the liver.

The results indicated that rats receiving daily injections of high doses of nanoparticles and those receiving weekly high doses showed greater effectiveness. They experienced a significant reduction in fat mass (by 50%), while their muscle mass increased by 6%. The next most effective was the "Orlistat" group, which achieved a reduction in body fat mass without affecting muscle mass.

Analysis of liver tissues across the six groups revealed varying outcomes. In rats from the high-dose gold nanoparticle group (daily administration), liver cells almost completely recovered. Signs of inflammation disappeared, and mitochondria were restored, enabling them to produce energy comparable to that of a healthy human liver without excess weight. Improvements were also observed in groups receiving weekly nanoparticle injections, although these were less pronounced. In contrast, the "Orlistat" group showed minimal improvements: inflammation decreased, new cell growth was initiated, but mitochondrial restoration was insufficient.

Blood test results were also best in the rats receiving high doses of gold nanoparticles. In these groups, total blood cholesterol levels and fasting blood sugar levels approached those of a healthy individual. "Orlistat" also lowered blood parameters; however, a significant difference was noted in the reduction of malondialdehyde—a marker of oxidative stress, where a high level indicates liver cell damage. The level of malondialdehyde decreased less markedly with "Orlistat" compared to the gold nanoparticle dosages. This was further confirmed by histological examination of the liver.

The findings from this new study offer hope for treating obesity without adverse effects on the gastrointestinal tract and liver. In the future, it will be essential for scientists to determine the correct dosage and treatment regimen.