CALERIE

Last updated

CALERIE (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy) is a trial currently underway in the U.S. to study the effects of prolonged calorie restriction on healthy human subjects.

Contents

The CALERIE study is being carried out at the Pennington Biomedical Research Center (Baton Rouge, Louisiana), the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University (Boston, Massachusetts) and the Washington University School of Medicine (St. Louis, Missouri). [1] It is hoped that caloric restriction reduces the incidence of cardiovascular disease and cancer and leads to a longer life, as has been demonstrated previously in numerous animal studies. [2] CALERIE is the first study to investigate prolonged calorie restriction in healthy humans. Study subjects are selected from people who are not obese (because calorie restriction on obese people is already known to lengthen life, but possibly for different reasons). [3]

A smaller predecessor study ended in 2006. Forty-eight subjects were randomly assigned to a control group and a treatment group; those in the treatment group were put on a 25% calorie reduction over a 6-month period. It was found that the treatment group had lower insulin resistance, lower levels of LDL cholesterol, lower body temperature and blood-insulin levels as well as less oxidative damage to their DNA. [3]

The second, larger, phase of CALERIE began in 2007. The participants are subjected to a 25% calorie restriction over a 2-year period, and several physiological variables are regularly monitored. Participants are paid $5,000 at Tufts and Pennington and $2,400 at Washington University. As of October 2009 the study had 132 participants and was still accepting new ones. [2]

Study subjects have to be highly motivated and organized enough to keep a detailed journal of all foods they eat. Their daily baseline calorie requirements are precisely determined before the trial: in a two-week laboratory test the rate of carbon dioxide production is measured, allowing to compute the number of burned calories. The subjects are then taught a diet of low-energy density foods, such as vegetables, fruits (especially apples [4] ), insoluble fiber and soups. Most subjects reported that they felt hungry for the first few weeks, after which they adjusted to the new diet. Complaints focused on the rigid bookkeeping scheme imposed on them. [2]

Results were posted to the Clinical Trial website in 2018 with a (paywalled) Lancet article [5] published in 2019. MSN published article [6] based on an interview with Dr Kraus.

Background

That calorie restriction (CR) might lengthen human lifespan was suggested by various studies on laboratory animals. However, when the studies were extended to long-lived primates (rhesus monkeys), while it was indeed found in a 2012 study by the US National Institute on Aging (NIA) that CR had benefits to immune function, motor coordination, and resistance to sarcopenia, a CR regimen implemented in rhesus monkeys of various ages did not improve survival outcomes.

The authors considered that the study suggested "a separation between health effects, morbidity and mortality", and that "study design, husbandry and diet composition may strongly affect the life-prolonging effect of CR in a long-lived non-human primate". [7]

Related Research Articles

Dieting is the practice of eating food in a regulated way to decrease, maintain, or increase body weight, or to prevent and treat diseases such as diabetes and obesity. As weight loss depends on calorie intake, different kinds of calorie-reduced diets, such as those emphasising particular macronutrients, have been shown to be no more effective than one another. As weight regain is common, diet success is best predicted by long-term adherence. Regardless, the outcome of a diet can vary widely depending on the individual.

<span class="mw-page-title-main">Abdominal obesity</span> Excess fat around the stomach and abdomen

Abdominal obesity, also known as central obesity and truncal obesity, is the human condition of an excessive concentration of visceral fat around the stomach and abdomen to such an extent that it is likely to harm its bearer's health. Abdominal obesity has been strongly linked to cardiovascular disease, Alzheimer's disease, and other metabolic and vascular diseases.

<span class="mw-page-title-main">Low-carbohydrate diet</span> Diets restricting carbohydrate consumption

Low-carbohydrate diets restrict carbohydrate consumption relative to the average diet. Foods high in carbohydrates are limited, and replaced with foods containing a higher percentage of fat and protein, as well as low carbohydrate foods.

A low-protein diet is a diet in which people decrease their intake of protein. A low-protein diet is used as a therapy for inherited metabolic disorders, such as phenylketonuria and homocystinuria, and can also be used to treat kidney or liver disease. Low protein consumption appears to reduce the risk of bone breakage, presumably through changes in calcium homeostasis. Consequently, there is no uniform definition of what constitutes low-protein, because the amount and composition of protein for an individual with phenylketonuria would differ substantially from one with homocystinuria or tyrosinemia.

<span class="mw-page-title-main">Weight gain</span> Increase in a persons total body mass

Weight gain is an increase in body weight. This can involve an increase in muscle mass, fat deposits, excess fluids such as water or other factors. Weight gain can be a symptom of a serious medical condition.

Calorie restriction is a dietary regimen that reduces the energy intake from foods and beverages without incurring malnutrition. The possible effect of calorie restriction on body weight management, longevity, and aging-associated diseases has been an active area of research.

Specific dynamic action (SDA), also known as thermic effect of food (TEF) or dietary induced thermogenesis (DIT), is the amount of energy expenditure above the basal metabolic rate due to the cost of processing food for use and storage. Heat production by brown adipose tissue which is activated after consumption of a meal is an additional component of dietary induced thermogenesis. The thermic effect of food is one of the components of metabolism along with resting metabolic rate and the exercise component. A commonly used estimate of the thermic effect of food is about 10% of one's caloric intake, though the effect varies substantially for different food components. For example, dietary fat is very easy to process and has very little thermic effect, while protein is hard to process and has a much larger thermic effect.

A negative-calorie food is food that supposedly requires more food energy to be digested than the food provides. Its thermic effect or specific dynamic action—the caloric "cost" of digesting the food—would be greater than its food energy content. Despite its recurring popularity in dieting guides, there is no evidence supporting the idea that any food is calorically negative. While some chilled beverages are calorically negative, the effect is minimal and requires drinking very large amounts of water, which can be dangerous, as it can cause water intoxication.

The CRON-diet is a nutrient-rich, reduced calorie diet developed by Roy Walford, Lisa Walford, and Brian M. Delaney. The CRON-diet involves calorie restriction in the hope that the practice will improve health and retard aging, while still attempting to provide the recommended daily amounts of various nutrients. Other names include CR-diet, Longevity diet, and Anti-Aging Plan. The Walfords and Delaney, among others, founded the CR Society International to promote the CRON-diet.

The term "infectobesity" refers to the hypothesis that obesity in humans can be caused by pathogenic organisms, and the emerging field of medical research that studies the relationship between pathogens and weight gain. The term was coined in 2001 by Dr. Nikhil V. Dhurandhar, at the Pennington Biomedical Research Center.

The Dietary Approaches to Stop Hypertension or the DASH diet is a diet to control hypertension promoted by the U.S.-based National Heart, Lung, and Blood Institute, part of the National Institutes of Health (NIH), an agency of the United States Department of Health and Human Services. The DASH diet is rich in fruits, vegetables, whole grains, and low-fat dairy foods. It includes meat, fish, poultry, nuts, and beans, and is limited in sugar-sweetened foods and beverages, red meat, and added fats. In addition to its effect on blood pressure, it is designed to be a well-balanced approach to eating for the general public. DASH is recommended by the United States Department of Agriculture (USDA) as a healthy eating plan. The DASH diet is one of three healthy diets recommended in the 2015–20 U.S. Dietary Guidelines, which also include the Mediterranean diet and a vegetarian diet. The American Heart Association (AHA) considers the DASH diet "specific and well-documented across age, sex and ethnically diverse groups."

Intermittent fasting is any of various meal timing schedules that cycle between voluntary fasting and non-fasting over a given period. Methods of intermittent fasting include alternate-day fasting, periodic fasting, such as the 5:2 diet, and daily time-restricted eating.

In biology, energy homeostasis, or the homeostatic control of energy balance, is a biological process that involves the coordinated homeostatic regulation of food intake and energy expenditure. The human brain, particularly the hypothalamus, plays a central role in regulating energy homeostasis and generating the sense of hunger by integrating a number of biochemical signals that transmit information about energy balance. Fifty percent of the energy from glucose metabolism is immediately converted to heat.

The anti-aging movement is a social movement devoted to eliminating or reversing aging, or reducing the effects of it. A substantial portion of the attention of the movement is on the possibilities for life extension, but there is also interest in techniques such as cosmetic surgery which ameliorate the effects of aging rather than delay or defeat it.

Management of obesity can include lifestyle changes, medications, or surgery. Although many studies have sought effective interventions, there is currently no evidence-based, well-defined, and efficient intervention to prevent obesity.

<span class="mw-page-title-main">Criticism of fast food</span>

Criticism of fast food includes claims of negative health effects, animal cruelty, cases of worker exploitation, children-targeted marketing and claims of cultural degradation via shifts in people's eating patterns away from traditional foods. Fast food chains have come under fire from consumer groups, such as the Center for Science in the Public Interest, a longtime fast food critic over issues such as caloric content, trans fats and portion sizes. Social scientists have highlighted how the prominence of fast food narratives in popular urban legends suggests that modern consumers have an ambivalent relationship with fast food, particularly in relation to children.

Rozalyn (Roz) Anderson is a professor at the University of Wisconsin School of Medicine and Public Health. She studies aging and caloric restriction in primates.

<span class="mw-page-title-main">Luigi Fontana (medical researcher)</span> Italian/Australian physician scientist, professor, environmentalist and author

Luigi Fontana, M.D., PhD, FRACP is a physician scientist who studies healthy longevity, with a focus on calorie restriction, endurance exercise and metabolism. He is the Leonard P Ullmann Chair in Translational Metabolic Health at the Charles Perkins Centre, where he directs the Charles Perkins Centre Royal Prince Alfred Clinic and the CPC RPA Health for Life Research, Educational and Clinical Program. He is also a Professor of Medicine and Nutrition in the Faculty of Medicine and Health at the University of Sydney and a Clinical Academic in the Department of Endocrinology at the Royal Prince Alfred Hospital in Sydney, Australia. Fontana was a professor of medicine and co-Director of the Healthy Longevity Program at Washington University School of Medicine.

Leanne M. Redman is a physiologist. She is an LPFA Endowed Fellowship Professor at the Pennington Biomedical Research Center of the Louisiana State University System, where she studies childhood obesity. She was lead researcher on a study that found that low-calorie diets decreased the effects of aging. Redman received the 2018 NPA Garnett-Powers & Associates Mentor Award in recognition of support for post-doctorate mentee scholars in her reproductive endocrinology lab. In October 2023, Redman was honored by The Obesity Society with the 2023 TOPS Research Achievement Award, in recognition to her contributions to the field of obesity.

The relationship between diet and longevity encompasses diverse research studies involving both humans and animals, requiring an analysis of complex mechanisms underlying the potential relationship between various dietary practices, health, and longevity.

References

  1. ↑ About CALERIE Archived 2010-02-12 at the Wayback Machine , retrieved 12 October 2009.
  2. 1 2 3 Gertner, Jon (2009-10-07). "The Calorie-Restriction Experiment". The New York Times Magazine. ISSN   0362-4331.
  3. 1 2 Eat less, live more, The Economist, April 22, 2006. ISSN   0013-0613
  4. ↑ "Kalorien Apfel" [Calories in an Apple]. JBahmann (in German). Retrieved 2024-08-27.
  5. ↑ Kraus, W. E.; Bhapkar, M.; Huffman, K. M.; Pieper, C. F.; Krupa Das, S.; Redman, L. M.; Villareal, D. T.; Rochon, J.; Roberts, S. B.; Ravussin, E.; Holloszy, J. O.; Fontana, L.; CALERIE Investigators (2019). "2 years of calorie restriction and cardiometabolic risk (CALERIE): exploratory outcomes of a multicentre, phase 2, randomised controlled trial". The Lancet. Diabetes & Endocrinology. 7 (9): 673–683. doi:10.1016/S2213-8587(19)30151-2. PMC   6707879 . PMID   31303390.
  6. ↑ O’Connor, Anahad (2019-07-16). "Cutting 300 Calories a Day Shows Health Benefits". The New York Times. ISSN   0362-4331 . Retrieved 2024-08-06.
  7. ↑ Mattison, Julie A.; Roth, George S.; Beasley, T. Mark; Tilmont, Edward M.; Handy, April M.; Herbert, Richard L.; Longo, Dan L.; Allison, David B.; Young, Jennifer E.; Bryant, Mark; Barnard, Dennis; Ward, Walter F.; Qi, Wenbo; Ingram, Donald K.; de Cabo, Rafael (2012). "Impact of caloric restriction on health and survival in rhesus monkeys from the NIA study". Nature. 489 (7415): 318–321. Bibcode:2012Natur.489..318M. doi:10.1038/nature11432. ISSN   0028-0836. PMC   3832985 . PMID   22932268.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.