Moderately reducing calories in non-obese people reduces inflammation

July 14, 2016, Tufts University

Eating less may help us lead longer, healthier lives, according to the new results from a large, multicenter study, led by researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University. The paper, published in Aging, reveals that restricting calories by 25 percent in healthy non-obese individuals over two years, while maintaining adequate protein, vitamin, and mineral intake, can significantly lower markers of chronic inflammation without negatively affecting other parts of the immune system.

"Previous studies in animals and simple model organisms over the past 85 years have supported the notion that can increase the lifespan by reducing and other chronic disease risk factors, but with mixed results about whether it has a negative or null effect on cell-mediated immune responses," said first and corresponding author Simin Nikbin Meydani, D.V.M., Ph.D., director of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts (HNRCA) and the director of its Nutritional Immunology Laboratory. "This is the first study to examine these effects over two years on healthy, normal- or slightly over- weight individuals and observe that caloric restriction reduces inflammation without compromising other key functions of the immune system such as antibody production in response to vaccines."

Chronic inflammation has been shown to create successions of destructive reactions that damage cells, thus playing a major role in the development of age-related diseases such as cancer, heart disease, and dementia. According to the Centers for Disease Control and Prevention (CDC), seven of the top 10 causes of death in 2010 were chronic diseases, with heart disease and cancer accounting for nearly 48 percent of all deaths. The CDC also reports in that same year 86 percent of all health care spending was for people with one or more chronic medical conditions.

After six weeks of baseline testing, which included metabolic measurements to determine their total daily energy expenditure, and blood collection to evaluate inflammation and cell-mediated immunity markers, 220 eligible individuals were randomized into two groups and further stratified by site, sex, and body mass index.

The control group maintained their normal diet for the duration of the study, while the test group was provided with support to maintain a high-satiety diet that restricted their calories by 25 percent including customized behavioral guidance. The test group was also given multivitamin and mineral supplements to prevent micronutrient malnutrition. To maintain a 25 percent reduction in calories the test group's calorie prescriptions were reduced three times through the two-year study to coincide with their weight loss based on body fat, and muscle mass calculations.

Both inflammation and immunity biomarkers were measured at baseline, 12 months, and at 24 months. Response to vaccines was determined at the end of the study. As an indicator of susceptibility to infectious disease, cell-mediated immunity was measured by antibody response to three vaccines and skin prick tests, white blood cell count, and self-reported illness. In addition, inflammation was monitored using serum levels of common inflammatory markers, including C-reactive protein, TNF alpha, and leptin.

The research team found that the test group had a significant and persistent reduction in inflammatory markers with no discernible difference in immune responses from the control group at the end of 24 months. However, while reduction in weight, fat mass, and leptin levels were most pronounced at 12 months they were not accompanied by the significant reduction in C-reactive protein and TNF alpha, both indicators of inflammation, until 24 months. This delay suggests that long-term calorie restriction, at least 24 months, induces other mechanisms that may play a role in the reduction of inflammation.

"This may be one of the most powerful non-genetic intervention to slow aging, increase our health span and the quality of our lives," continued Meydani of the HRNCA. She is also a professor at the Friedman School of Nutrition Science and Policy, Tufts University School of Medicine, and a member of the immunology program faculty at the Sackler School of Graduate Biomedical Sciences at Tufts.

"These calorie restricted changes suggest a shift toward a healthy phenotype given the established role of inflammation in the development of cardiovascular disease, cancer and aging. With all of today's fitness and biometric measurement technology available to the public, it is certainly feasible for the average person to maintain a 10-15 percent calorie restriction as a strategy for long-term health benefits," said co-author Luigi Fontana, M.D., Ph.D., professor of medicine and nutrition at Washington University in St. Louis and Brescia University (Italy).

Explore further: How a low-calorie diet could extend lifespan

Related Stories

How a low-calorie diet could extend lifespan

June 29, 2016
Overeating can lead to health issues that can shorten one's life, such as obesity, diabetes and heart disease. On the other end of the spectrum, several studies have shown that restricting calorie intake below what a normal ...

Poor sleep health could contribute to inflammatory disease

July 6, 2016
A new meta-analysis in Biological Psychiatry reports that sleep disturbances and long sleep duration are associated with increases in markers of inflammation.

Study links some positive effects to calorie restriction in nonobese adults

May 2, 2016
A 25 percent calorie restriction over two years by adults who were not obese was linked to better health-related quality of life, according to the results of a randomized clinical trial published online by JAMA Internal Medicine.

Weight loss plus vitamin D reduces inflammation linked to cancer, chronic disease

June 25, 2015
For the first time, researchers at Fred Hutchinson Cancer Research Center have found that weight loss, in combination with vitamin D supplementation, has a greater effect on reducing chronic inflammation than weight loss ...

Recommended for you

Americans are getting more sleep

January 19, 2018
Although more than one in three Americans still don't get enough sleep, a new analysis shows first signs of success in the fight for more shut eye. According to data from 181,335 respondents aged 15 and older who participated ...

Wine is good for you—to a point

January 18, 2018
The Mediterranean diet has become synonymous with healthy eating, but there's one thing in it that stands out: It's cool to drink wine.

Sleep better, lose weight?

January 17, 2018
(HealthDay)—Sleeplessness could cost you when it's time to stand on your bathroom scale, a new British study suggests.

Who uses phone apps to track sleep habits? Mostly the healthy and wealthy in US

January 16, 2018
The profile of most Americans who use popular mobile phone apps that track sleep habits is that they are relatively affluent, claim to eat well, and say they are in good health, even if some of them tend to smoke.

Improvements in mortality rates are slowed by rise in obesity in the United States

January 15, 2018
With countless medical advances and efforts to curb smoking, one might expect that life expectancy in the United States would improve. Yet according to recent studies, there's been a reduction in the rate of improvement in ...

Can muesli help against arthritis?

January 15, 2018
It is well known that healthy eating increases a general sense of wellbeing. Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have now discovered that a fibre-rich diet can have a positive influence ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.