Researchers from the University of Iowa (UI) performed a new study that suggest that apple peels and green tomatoes could help decrease muscle tissue loss. Both fruits have some compounds which are capable to help reduce the negative effects from a protein named ATF4 and to maintain our muscle mass healthy and complete.

The team from the UI found that ATF4 protein was involved in the process of muscle aging. This protein is a transcription factor -DNA into RNA converter – that takes big part in the expression of selected genes in our skeletal muscles which are the ones that are attached to the bones – almost all body movement from walking to grabbing apples in the fridge is caused by contractions of those muscles. In that sense, ATF4 proteins reduce our strength, muscle mass and the synthesis of muscle protein.

An apple peel has chemical compounds that help prevent muscle tissue loss in aging and sedentary people. Credit: FoodOnFifth

“Many of us know from our own experiences that muscle weakness and atrophy are big problems as we become older,” stated senior study author Dr. Christopher Adams to Jennifer Brown from IowaNow. Adams is a professor of internal medicine at the University of Iowa Carver College of Medicine.

Christopher Adams, along with his associates, noticed in a previous investigation – long before this study – two natural compounds that were crucial to prevent muscle tissue loss as a result of sedentary habits and bad nutrition. The protagonistic compounds drawn from that previous examination were the ursolic acid, and tomatidine – which are found in apple peels and green tomatoes respectively.

From those findings, researchers proceeded to investigate the molecular effects of both ursolic acid and tomatidine in aged skeletal muscle.


In order to test their theory, researchers based their investigation on an aged mice with age-related muscle feebleness. Scientists began to feed the mice lacking ATF4 in skeletal muscle with specific amounts of ursolic acid and tomatidine – 0.27 percent or 0.05 percent, respectively – During a period of two months, researchers were evaluating the effects on the mice’s muscles.

“Based on these results, ursolic acid and tomatidine appear to have a lot of potential as tools for dealing with muscle weakness and atrophy during ageing. By reducing ATF4 activity, ursolic acid and tomatidine allow skeletal muscle to recover from effects of ageing.” Lead author stated after the evaluation.

The results

Adams explained that these findings provided essential tools as ursolic acid and tomatidine, to deal with muscle weakness and atrophy during aging. Scientists determined that both compounds increased the amount of mass in aged-individuals by 10 percent – and also improved their performance and strength even by 30 percent –

The team discovered that by reducing ATF4 activity, ursolic acid and tomatidine will allow skeletal muscle to fight against the effects of aging. To conclude, Adams added “If ursolic acid- and tomatidine-based approaches are found to be safe and effective in humans, they could possibly be used alone, together, or in combination with physical therapy and other nutritional and pharmaceutical approaches.”

In addition to Adams, the UI team included Michael Dyle, Steven Bullard, Jason Dierdorff, Daryl Murry, Daniel Fox, Kale Bongers, Vitor Lira, and David Meyerholz, as well as Scott Ebert and John Talley at Emmyon, Inc.

Source: Medical News Today