Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

People who restrict calories have ’younger’ hearts

16.01.2006


Study is first to associate calorie restriction with delayed primary aging in humans



The hearts of people who follow a low-calorie, yet nutritionally balanced, diet resemble those of younger people when examined by sophisticated ultrasound function tests, and they tend to have more desirable levels of some markers of inflammation and fibrosis, according to a new study in the Jan. 17, 2006, issue of the Journal of the American College of Cardiology.

"Eating less, if it is a high-quality diet, will improve your health, delay aging, and increase your chance of living a long, healthy and happy life," said Luigi Fontana, M.D., Ph.D., from the Washington University School of Medicine in St. Louis, Missouri and the Italian National Institute of Health in Rome, Italy. "This is the first paper to show that long-term calorie restriction with optimal nutrition has cardiac-specific effects that ameliorate the age-associated decline in diastolic function in humans. In other words, this is the first report ever to show that calorie restriction with optimal nutrition may delay primary aging in human beings."


A number of studies have shown that animals can live longer when they eat fewer calories, but human study has been difficult. The caloric restriction model requires a strict diet regimen, both to keep the total number of calories low and to insure that participants consume the right balance of nutrients.

Rather than try to randomize volunteers to different diets and then hope that they will stick to them for years, the researchers, including first author Timothy E. Meyer, Ph.D., compared 25 people who already had been following caloric restriction for an average of six years (consuming about 1,400 to 2,000 calories per day) with 25 similar control subjects who were eating typical Western diets (about 2,000 to 3,000 calories per day).

Hearts tend to stiffen and pump less effectively as people get older, but ultrasound examinations showed that the hearts of the people on caloric restriction appeared more elastic than those of the control subjects; that is, the hearts relaxed between beats in a way that is similar to the hearts of younger people. In addition, several heart disease risk factors and inflammatory markers--blood pressure, C-reactive protein, tumor necrosis factor-alpha (TNF-á), and transforming growth factor-beta1 (TGF-â1)--were lower in the caloric restriction group than in the Western diet group.

Dr. Fontana, who designed and led the study, emphasized that caloric restriction does not mean simply eating less.­

"Calorie restriction is associated with longevity only when is coupled with optimal nutrition. On the other hand, calorie restriction coupled with malnutrition accelerates aging and causes severe diseases. Therefore, eating half a hamburger, half a bag of French fries and half a can of soft drink is not healthy caloric restriction and is harmful," he said. "It is important to note that the caloric-restriction subjects ate a healthful balanced diet with at least 100 percent of the recommended daily intake of each nutrient, providing approximately 1,671 plus or minus 294 kilocalories per day. The average diet was 23 percent protein, 49 percent complex carbohydrates, and 28 percent fat, including 6 percent saturated fat. Daily salt intake was lower in the caloric-restriction group compared to the Western diet group."

Dr. Fontana said that the diets of people on caloric restriction resemble the traditional Mediterranean diet, which is based on a wide variety of vegetables, olive oil, beans, whole grains, fish and fruit. The diet avoids refined and processed foods, soft drinks, desserts, free sugars, white bread and white pasta.

While many people could adopt some of these diet practices, Dr. Fontana cautioned that anyone attempting to follow a strict caloric-restriction diet should have expert guidance, because of the risk of malnourishment if the diet does not include the right amounts of key nutrients.

The authors noted that the study design had some limitations.

"Because our study was not randomized, our cross-sectional study design does not allow us to assign causation, although the observed significant differences on the basis of cross-sectional data are an important first step in elucidating the effects of long-term caloric restriction in humans," they wrote.

The lower levels of C-reactive protein and other inflammatory cytokines may indicate that caloric restriction helps to reduce damage from chronic inflammation in the body.

"It is well known that overweight and obese people have a low-grade chronic inflammatory state. This is due to the fact that hypertrophic fat cells chronically produce inflammatory molecules that are released in the blood stream. This means that body tissues in overweight and obese subjects are chronically exposed to inflammatory stimuli. It is our hypothesis that this chronic inflammation causes chronic tissue damage and associated adaptative fibrosis that leads to premature and accelerated tissue and organ hardening," Dr. Fontana said.

Gary Gerstenblith, M.D., F.A.C.C., from the Johns Hopkins Hospital in Baltimore, Md. wrote in an editorial in the journal that the study is the first to describe the effects of calorie restriction on a well-recognized marker of cardiovascular aging in humans. However, he pointed out that it is unlikely that many people would be able to successfully adopt such a strict diet.

"The value of the study is that it points to possible mechanisms explaining how aging occurs and, therefore, how it may be modified. The authors,and the disciplined volunteers following the practice of caloric restriction are to be congratulated for their important contributions to this effort," Dr. Gerstenblith wrote.

Daniel E. Forman, M.D., F.A.C.C., from the Boston Medical Center, who was not connected with this study, said that the researchers have presented exciting data showing benefits of caloric restriction.

"These data provide insight into the impact of diet on intrinsic myocardial function. Our normal Western diet likely induces inflammatory peptides that bring about changes in ventricular histology and function, including higher collagen content and associated tissue stiffening. Nutritionally balanced caloric restriction may constitute a key means to modify these detrimental patterns and mitigate age-related morbidity and mortality," Dr. Forman said.

Amy Murphy | EurekAlert!
Further information:
http://www.acc.org

More articles from Studies and Analyses:

nachricht Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung

nachricht Scientists reveal source of human heartbeat in 3-D
07.08.2017 | University of Manchester

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

On the way to developing a new active ingredient against chronic infections

21.08.2017 | Life Sciences

Smart Computers

21.08.2017 | Information Technology

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>