KATHMANDU — Putting just a bit less on your dinner plate each day reducing caloric intake might be key to a longer life, a preliminary research has suggested.
According to a small clinical trial, people who reduced their caloric intake by just 15 percent over two years experienced a significant decrease in their metabolism.
These people also saw improvements in biomarkers associated with slower aging and longer life span, said lead researcher Leanne Redman, an associate professor of clinical sciences at Pennington Biomedical Research in Baton Rouge, La.
For the study published March 22 in the journal Cell Metabolism, Redman’s team recruited 34 healthy people with an average age of 40 to follow a calorie-restricted diet for two years.
The researchers found that the participants developed a lower core body temperature, lower blood sugar and insulin levels, and significant drops in hormones that moderate metabolism.
“We know these things are lower in people who live longer lives,” Redman said.
Researchers taught the study participants how to cut 25 percent of their daily caloric intake using three different models of a healthy diet, Redman said.
The participants then were free to follow their diet by any means they chose.
“On their own, they achieved a 15 percent reduction in calorie intake that was sustained for the two years, which is pretty remarkable,” Redman said.
On average, the group lost about 20 pounds, mostly in the first year, even though half entered the study at normal weight and the rest were only modestly overweight, Redman said.
Aging studies in animals have tied lower calorie intake to longer lives, but this is the first clinical trial to bridge the gap between animals and humans, said Rozalyn Anderson, an expert with the American Federation for Aging Research who reviewed the findings.
“So much of what they’re reporting is entirely consistent with what we’ve seen in our monkey studies,” said Anderson, an associate professor who studies aging and calorie restriction at the University of Wisconsin School of Medicine and Public Health.
“We’ve got a match between the monkeys and the humans, and that’s absolutely brilliant. This is a really neat gap to have closed in terms of aging biology,” she said.
The researchers said this offers support to controversial theories linking high metabolism and increased oxidative stress to faster aging.
“When we make energy, we have byproducts of metabolism, and these byproducts called oxygen radicals accumulate in the body and cause damage to cells and tissues,” Redman said. Such damage can cause cells to age faster and contribute to diseases like cancer.
Anderson isn’t so sure that’s the best explanation. She noted that lab studies in mice have shown that damage done by oxidative stress has no effect on overall life span.
Anderson thinks lower calorie intake prompts the body to use energy more efficiently, and that somehow results in benefits for aging.
“We know, for example, there’s a really tight connection that we don’t understand between fasting and resilience — the ability to stand up against distress,” Anderson said.
People who want to try to eat less in an attempt to live longer should focus on portion size while following a healthy and well-balanced diet, Redman said.
They should aim for lowering calorie intake by 25 percent, with the understanding that they will probably fall short of the goal, Redman said. They shouldn’t be discouraged if they don’t keep losing weight long-term.
“The goal is not to lose weight. The goal is to have this sustained lower intake,” Redman said.
Excess use of social media may lead to depression and loneliness
Excessive use of social media like Facebook, Snapchat or Instagram could lead to depression and loneliness as this habit is associated with poor well-being,researchers have warned.
A new study, being published in the Journal of Social and Clinical Psychology by researchers at the University of Pennsylvania, showed that limiting screen time on these apps could boost one’s wellness.
The study has tried to look into the causal side of things, and see whether people may actually feel better when they cut down on social media.
“Our findings strongly suggest that limiting social media use to approximately 30 minutes per day may lead to significant improvement in well-being,” the authors concluded.
“When you are not busy getting sucked into clickbait social media, you are actually spending more time on things that are more likely to make you feel better about your life,” said Melissa Hunt, associate director of clinical training at the University of Pennsylvania in the US.
For the study, researchers from the varsity, included 143 undergraduate participants. The team designed their experiment to include the three platforms most popular with the participants.
They monitored the students for a week to get a baseline reading of their social media use, and gave them questionnaires that assessed their well-being according to seven different factors: social support, fear of missing out (aka FOMO), loneliness, autonomy and self-acceptance (a measure of psychological well-being), anxiety, depression, and self-esteem.
They collected objective usage data automatically tracked by iPhones for active apps, not those running in the background, and asked respondents to complete a survey to determine mood and well-being.
“Using less social media than you normally would leads to significant decreases in both depression and loneliness. These effects are particularly pronounced for folks who were more depressed when they came into the study,” Hunt told Science Daily.
The researchers chose to limit social media, rather than have subjects stop using it altogether, because it was a more realistic option, she noted.