![]() |
|
![]()
August 29th, 2012
01:01 PM ET
Restricting calories may not prolong your lifeCalorie restriction has long been used to examine aging in rodents and monkeys. Past studies have shown that restricting calories in a nutritious diet by 10 to 40% can delay or prevent chronic diseases, slow aging and increase life spans. But new research published this week in the journal Nature shows quite the opposite – that calorie restriction does not improve survival outcomes. Turns out, the issue may be more complicated than first thought. The study Researchers at the National Institute of Aging have been studying the effects of calorie restriction in rhesus monkeys for more than 20 years in hopes of eventually applying the results to humans. Male and female monkeys of all ages are enrolled in the study. The experimental group eats approximately 25% fewer calories than the control group. Any animal that dies during the study undergoes a necropsy (an autopsy performed on an animal) to find the probable cause of death. Older monkeys who began the calorie-restricted diet weighed significantly less than monkeys in the control group. They had lower levels of triglycerides (fatty acids) and cholesterol. Yet the calorie-restricted older monkeys did not live any longer than their counterparts. There were also no apparent differences in the causes of death between the two. Twenty percent of the young monkeys in the calorie-restricted group have died of age-related causes, compared to 24% of the control group. The calorie-restricted younger monkeys weigh less, but do not have significantly lower levels of fasting glucose or triglycerides. Cancer rates were improved in the calorie-restricted group, but diabetes and cardiovascular disease were detected in both. “Even the control monkeys in our study are very healthy and demonstrate an increased survival relative to other captive populations of monkeys,” said study author Dr. Julie Mattison. “It is possible that we have maximized the survival benefits in our colony and thus a reduction in calories provides no further benefit relative to their very healthy control counterparts.” Approximately 50% of the younger monkeys in the study are still alive. Using the data already collected, researchers estimate a less than 0.1% chance that the calorie restriction diet will have a favorable effect on their survival. The other study Scientists at the Wisconsin National Primate Research Center are doing a parallel study using rhesus monkeys on a 30% calorie restricted diet. They have reported improved survival rates in their primates. Mattison says the differences in the monkeys’ diet composition in each study could contribute to the varying results. The NIA monkeys are from China and India, whereas the Wisconsin monkeys come only from India; the genetic makeup in each could be different. The NIA authors say further comparisons of the two studies are “warranted and planned.” The takeaway First and foremost, Mattison stresses that a calorie-restricted diet is meant for studying aging, not as a “prescription for human health.” Anyone interested in following a similar plan should first speak to their doctor. The second takeaway is that we still need more information. “The effects of (calorie restriction) are multi-faceted in a longer-lived subject such as a monkey and it is necessary to dissect the interplay of number of calories and source of calories," Mattison says. "Unless we understand which pathways are being affected by this metabolic stress, we can’t control the many other variables that might contribute to the effect." |
![]() ![]() ![]() ![]() About this blog
Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love. |
|
Cialis nova scotia cialis super active vs cialis professional how can i get cialis
in australia
30 day free trial of cialis cialis viagra mail order uk discrete billing cialis for sale in toront ontario
Does cialis delay ejaculation generic cialis with dapoxetine 80mg x 10 tabs generic cialis
sale
Buy cialis 10 tab maximum daily dose of cialis
buy cialis ireland
Cialis time bye cialis online from usa buy
cialis at walmart
Legal online pharmacies in the us pharmacy windsor canada canadian prescription pharmacy
Online pharmacy delivery medical pharmacies Mobic
My partner and I stumbled over here from a different web page and thought
I may as well check things out. I like what I see so now
i am following you. Look forward to looking at your web page
for a second time.
I am sure this post has touched all the internet users, its really really fastidious
article on building up new website.
Northwest pharmacy certified canadian pharmacies prescription drugs definitions
Awesome! Its really awesome piece of writing, I have got much clear idea on the topic of from this
piece of writing.
Most dangerous prescription drugs canadian overnight pharmacy review canadian pharmacy lantus
Canadian pharmacy cialis brand cialis dick cialis sales
canadian
Staxyn vs cialis generic cialis 30 pills 20mg inexpensive cialis
I have been browsing online greater than three hours these days, but I never found any interesting article like yours.
It's beautiful worth sufficient for me. In my opinion, if all webmasters and bloggers made excellent content material as you did,
the web will probably be much more helpful than ever before.
Here is my web blog; Kristian
Buy cialis without presc cialis use instructions generic daily cialis
Overnight pharmacy cialis the cost of cialis \'generic cialis\'
Cialis levitra how to order cialis from canada generic cialis india safe
Cialis for daily use disount cialis 36 hour dosage
cialis drugs
Generic cialis 5mg cialisis online cialis
australia
By cialis tablets in frankfurt pharmacy cialis 20mg what does cialis
treat
Cialis 20mg prices can cialis be taken with food alternatives to cialis
Weight loss drugs approved in canada online pharmacy oxycodone 30mg health canada controlled drugs and substances
Cialis doesn\'t work do have to have a prescription for cialis? What are the ingredients in cialis
Drug store Prometrium discount drugs online pharmacy
Rx good neighbor pharmacy viagra canadian pharmacy legit canadian mail order pharmacy ratings
Cialis 20 mg price costco cialis dosage strengths
how much are cialis pills
Is cialis when does cialis lose its patent cialis
for pulmonary hypertension
Free samples of cialis canadian online pharmacy cialis cialis free trial
Best rx online pharmacy cvs pharmacy store finder Sinemet
Cialis dapoxetine brand cialis australia buy
cialis on line without presciption
Pretty nice post. I just stumbled upon your blog and wanted to say that I have truly enjoyed browsing
your blog posts. After all I'll be subscribing to your feed and I hope you write again soon!
Also visit my blog ... phentermine review
Cheap cialis australia cialis bathtub commercial cialis 200 mg
no prescription
Generic drug name for cialis cialis and viagra together forum free sample of cialis
Motilium pharmacy rx one reviews canadian pharmacy
propecia
Ez pharmacy canada pharmacy generic cialis ed drugs canada
hydroxychoriquin https://pharmaceptica.com/
Tadalafil (cialis) online cialis reviews what to do if cialis doesnt work
Keep this going please, great job!
Buy cialis with dapoxetine cialis daily review cialis maximum daily dose
Prescription free cialis cialis and alcohol reddit brand cialis for
sale
Canadian pharmacy cialis no prescription what happens when a woman takes cialis canadian cialis reviews
Where to buy cialis online for cheap buy cialis online india
viagra cialis meds
Buy cialis 365 pills how long does cialis stay in your system cialis risks
Script pharmacy canada pharmacy online legit Nootropil
Online pharmacy florida walgreens store locator 24 hour pharmacy legitimate canadian pharmacy list
what is hydroxychloroquine prescribed for https://pharmaceptica.com/
Canadian government approved online pharmacies okay google canadian pharmacies on the web pharmacy online prescription
Capoten canadian pharmacy adderall international drug mart canadian pharmacy online store
Cialis tablets buy cialis online free shipping voucher
cialis index