An anti-aging enzyme found in a number of natural foods, including broccoli, is showing promise in staving off the long-term effects of growing old – at least in mice.
Researchers led by scientists at the University of Washington in St. Louis have identified a compound known as nicotinamide mononucleotide – or NMN – that has essentially reversed the aging process in mice by halting the breakdown of specific cells in the body.
NMN is found in broccoli and a number of other foods, including avocados, cabbage, cucumbers and edamame, or soybeans.
Scientists realized a substantial impact of NMN consumption on mice, showing a reversal of cell-based energy loss and a reduction of aging-related signs that include a loss of insulin sensitivity and weight gain.
The researchers are hopeful that the positive effects on mice will someday translate to humans. In fact, earlier this year, the first phase of a human trial investigating NMN consumption began at the Keio University School of Medicine in Japan.
A closer look at the study
Over a 12-month study, the research team fed mice regular doses of NMN by adding it to their drinking water. The NMN-fed mice essentially stopped aging and showed clear signs of acting – physiologically – far younger.
“We have shown a way to slow the physiologic decline that we see in aging mice,” said Shin-ichiro Imai, MD, PhD, a professor of developmental biology and of medicine, in a news release.
“This means older mice have metabolism and energy levels resembling that of younger mice. Since human cells rely on this same energy production process, we are hopeful this will translate into a method to help people remain healthier as they age.”
The researchers believe that NMN prevents aging by blocking the gradual destruction of energy-creating mechanisms within cells. NMN works by enhancing the production of another substance called nicotinamide adenine dinucleotide (NAD), which decreases with age.
Past studies had shown that administering NAD directly didn’t work. So the researchers turned to NMN and found that direct doses contained in drinking water had a profound effect.
“We wanted to make sure that when we give NMN through drinking water, it actually goes into the blood circulation and into tissues,” Imai said. “Our data show that NMN absorption happens very rapidly.”
Notably, the effects of NMN are lost on young mice because they naturally create stores of the substance on their own, according to the study’s co-senior author, Dr. Jun Yoshino.
“When we give NMN to the young mice, they do not become healthier young mice,” Yoshino said. “NMN supplementation has no effect in the young mice because they are still making plenty of their own NMN. We suspect that the increase in inflammation that happens with aging reduces the body’s ability to make NMN and, by extension, NAD.”
Also, scientists had to be careful about administering NMN and creating other problems, such as cancer.
“Some tumor cells are known to have a higher capability to synthesize NAD, so we were concerned that giving NMN might increase cancer incidence,” Imai said. “But we have not seen any differences in cancer rates between the groups.”
Richard Scott is a health care reporter focusing on health policy and public health. Richard keeps tabs on national health trends from his Philadelphia location and is an active member of the Association of Health Care Journalists.