A new study from the University of Iowa have discovered a protein in the skin of apples and green tomatoes that can help prevent the loss of muscle mass and weakening as we age. Researchers discovered that within two months of eating the fruits’ skin, the atrophied muscles of an older person can be restored to that of a young person.
The study, published in the Journal of Biological Chemistry, is the first of its kind to identify the protein ATF4 as an essential mediator of muscle aging. This discovery could lead to new forms of treatment. Dr. Chistopher Adams, a professor of internal medicine at the University of Iowa Carver College of Medicine, was the lead author on the study.
“Many of us know from our own experiences that muscle weakness and atrophy are big problems as we become older. These problems have a major impact on our quality of life and health.”
Although the natural wasting of muscle as we age, also known as sarcopenia, is a well-accepted natural occurrence, why the decline in muscle occurs is still unknown. However, the study found that a protein called ATF4 changes the way genes are formed in the body. This leads to muscle starvation which deprives the muscle of the proteins they need to maintain mass and strength.
Previously, Dr. Adams and his team identified two natural compounds that prevent muscle wasting caused by inactivity and starvation. These compounds were ursolic acid, found in apple peel, and tomatidine, found in green tomatoes. Using these finding, the team then researched whether the compounds were also capable of preventing muscle wasting caused by aging, using older mice with age-related muscle weakness and atrophy.
“By reducing ATF4 activity, ursolic acid and tomatidine allow skeletal muscle to recover from effects of aging.”
The urosolic acid found in apple peels and the tomatidine found in green tomatoes effectively reduced the activity of ATF4. If consumed on a regular basis, older individuals can see results in two months.
“Initial tests on older mice show ursolic acid and tomatidine ‘dramatically reduce age-related muscle weakness and atrophy’, increasing muscle mass by 10% and ‘muscle quality’ by 30% after just two months.”
Dr. Adams continues on by saying, “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 aging.”
Starting at around the age of 30, we begin to lose muscle mass and function. This natural occurring process is referred to as sarcopenia. The word sarcopenia comes from the Greek words sacra, “flesh”, and penia, “poverty”. Those who are physically inactive can lose anywhere from between 3% to 5% of their muscle mass every decade after 30. Even those who are physically active will still lose some muscle mass.
Losing muscle mass means losing strength and mobility in the body. Although it is a gradual process, sarcopenia usually gets much worse at around the age of 75. Because of this, it leads to frailty and increases the chances of falls and fractures in older individuals.
Dr. Roger Fieldings of Tufts University believes that the increase of chronic diseases and conditions as aging progresses contribute to the worsening of physical and muscle function. He says that many older individuals do not realize that their decreased mobility is a result of weak muscles from a disease called sarcopenia.
“The thing that many older people worry about and are most afraid of is their loss of independence. I think we’ve done a really good job of treating a lot of the chronic diseases but there’s still this underlying loss of physical functioning.”
Besides the newly discovered ATF4 protein, researchers also suspect that a decrease in the hormones testosterone, growth hormone, and insulin-like growth factor may also play a part. The body’s decreased ability to make protein and not eating enough calories to sustain muscle mass may also be culprit to causing sarcopenia.
The absolute best way to prevent sarcopenia is by exercising. Resistance training and strength training – exercise that uses resistance to build muscles by using weights or resistance bands – is useful for both preventing and improving the effects of muscle wasting. In fact, as little as two weeks of resistance exercise shows great improvement in muscle mass and strength.
It is important that the intensity, the type of exercise, and the frequency of exercise is appropriate for the body in order to prevent injury. As always, speak to your primary care physician before you begin any exercise program, and work with a certified trainer if you are a beginner in order to help make sure you are performing the exercises correctly.