The CRON-diet (Calorie Restriction with Optimal Nutrition) is a nutrient-rich, reduced calorie diet developed by

Roy Walford Roy Lee Walford, M. D. (June 29, 1924 – April 27, 2004) was a professor of pathology at University of California, Los Angeles School of Medicine, a leading advocate of calorie restriction for life extension and health improvement, and a crew m ...

, Lisa Walford, and Brian M. Delaney. The CRON-diet involves

calorie restriction Calorie restriction (caloric restriction or energy restriction) is a dietary regimen that reduces intake of energy from caloric foods & beverages without incurring malnutrition. "Reduce" can be defined relative to the subject's previous intake b ...

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.

Context

There is no experimental evidence that

can slow

biological aging Senescence () or biological aging is the gradual deterioration of functional characteristics in living organisms. The word ''senescence'' can refer to either cellular senescence or to senescence of the whole organism. Organismal senescence inv ...

in humans. The biological mechanisms for the supposed antiaging effects are not determined, as of 2021.

Origins

The CRON-diet was developed from data Walford compiled during his participation in Biosphere 2 from 1991 to 1993. The subjects ate a diet low in fat and in calories but "nutrient-dense", derived from the food crops raised inside the Biosphere.

Debate on effectiveness

The writer

Christopher Turner Christopher Turner is a British writer. He has been a regular contributor to ''Cabinet'' magazine since 2004, and to the '' London Review of Books'' since 2001. He has also written for ''The Guardian'' and '' The Sunday Telegraph'', and is the e ...

in ''

The Telegraph ''The Telegraph'', ''Daily Telegraph'', ''Sunday Telegraph'' and other variant names are popular names for newspapers. Newspapers with these titles include: Australia * ''The Telegraph'' (Adelaide), a newspaper in Adelaide, South Australia, publ ...

'' reported that Walford claimed that the diet "will retard your rate of ageing, extend lifespan (up to perhaps 150 to 160 years, depending on when you start and how thoroughly you hold to it), and markedly decrease susceptibility to most major diseases." The same article noted however that the diet "failed to dramatically increase Walford's lifespan; he died in 2004 aged 79." A review of the effects of calorie restriction in humans by Anna Picca and colleagues in 2017 noted that direct evidence was limited to what had been "recorded from the members of the Calorie Restriction Society, who have imposed on themselves a regimen of severe CR with optimal nutrition (CRON), believing to extend in this way their healthy lifespan." The review noted that bone density was reduced but that bone strength was improved and maximal aerobic capacity per unit body mass was maintained or increased, while measures of quality of life including depression and physical function were improved. The review observed that one outcome had been the development of calorie restriction mimetic drugs which would be tested in clinical trials on humans.

Reception

The journalist

Pagan Kennedy Pagan Kennedy (born c. 1963) is an American citizen, American columnist and author, and pioneer of the 1990s zine movement. She has written ten books in a variety of genres, was a regular contributor to the ''Boston Globe'', and has published ar ...

wrote an opinion piece for ''

The New York Times ''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid d ...

'', mentioning Walford's book ''The 120 Year Diet'' and his hope of living for more than 100 years on the CRON diet, noting that instead he died of

Lou Gehrig disease Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND) or Lou Gehrig's disease, is a neurodegenerative disease that results in the progressive loss of motor neurons that control Skeletal muscle, voluntary muscles. ALS ...

at age 79: her piece was titled "The Secret to a Longer Life? Don't Ask These Dead Longevity Researchers". The journalist

Emily Yoffe Emily J. Yoffe (born October 15, 1955) is an American journalist and contributing writer for ''The Atlantic''. From 1998 to 2016 she was a regular contributor to ''Slate'' magazine, notably as Dear Prudence. She has also written for ''The New ...

tried the CRON-diet for '' Slate''. She wrote that Walford had written a book about the diet called ''Beyond the 120 Year Diet'', in which a "typical dinner" consisted of salad, lentils, brown rice,

bulgur Bulgur (from tr, bulgur, itself from fa, بلغور, bolġur (bolghur)/balġur (balghur), groats ), also riffoth (from biblical he, ריפות, riffoth) and burghul (from ar, برغل, burġul ), is a cracked wheat dish found ...

, a stalk of broccoli, and a glass of skimmed milk. Yoffe reported that after more than 2 months on the diet, she had not experienced the promised results: her "very poor" sleep had not improved much; her "energy" remained low; her "foggy mind" was still foggy. But she was pleased that she once again could experience loose-fitting pants.

References

{{reflist, 30em Diets Nutrient-rich, low calorie diets Eating behaviors