A General Interest Article on Calorie Restriction
From the Globe and Mail: "Brian Delaney, the president of the North Carolina-based Calorie Restriction Society International, is 48 years old, but he may as well be 25. Mr. Delaney, co-author of the book The Longevity Diet, began practising calorie restriction nearly two decades ago. He attributes his remarkably youthful condition to his active lifestyle and diet of less than 2,000 calories a day, compared with his prerestriction diet of about 3,000 calories a day. (Three thousand calories a day is on par with Health Canada's estimated energy requirements for active 19- to 30-year-old men.) As a participant in a calorie restriction study at the Washington University in St. Louis, he's had a variety of biomarkers measured, such as blood pressure levels, fasting glucose levels, cholesterol, DNA damage and arterial elasticity, and the results are typical of someone at least 20 years younger. ... 'I don't look 25. ... I look a little bit younger than I am,' he acknowledges, but those test results, he says, provide validation for limiting what he eats. In recent years, as calorie restriction has gained legitimacy, Mr. Delaney's society, which he helped create in 1994, has recorded a surge in membership. It now numbers roughly 2,500 members, including at least a few dozen based in Canada. 'We've seen a huge amount of growth in the last three or four years,' he says, 'and that's primarily because ... there have been a lot of new [human] studies coming out that confirm what most of us believed, based on past studies with laboratory animals.' ... It's impossible, however, for researchers to say whether calorie restriction can really lead to longevity in humans. That would require an unrealistically long study. But when it comes to 'secondary aging,' which is all the diseases associated with age and obesity, such as diabetes, cardiovascular disease, hypertension and some forms of cancers, [there's] no question that you would delay the occurrence of these diseases by calorie restriction."
"Brian Delaney... is 48 years old, but he may as well be 25". I love your links in general, but I call puffery on this one. If he looked young the article would have included a picture. Here is a link to a picture of him from a year ago
http://failuremag.com/index.php/feature/article/the_calorie_restriction_diet/
He looks maybe a few years younger than 47 in that picture. Yea, kind of an unscientific analysis but, given how unfit the average American is, most anyone that exercises regularly, does not abuse alcohol, tobacco or drugs, and maintains a BMI under 24 (I calculate his at 18.7) is going to have strong blood numbers compared to the norm and will look a few years younger than the norm, that is not validation in my mind.
@JohnD60: Agreed the 'may as well be 25' line is typical bad journalism from the article author. The changes to many biomarkers that come with calorie restriction are noteworthy, however, and do typically look like those of a young adult or even child. See for example:
https://www.fightaging.org/archives/2004/04/impressive-calorie-restriction-statistics.php
There is a big difference between what exercise does to these markers and what calorie restriction does, so that's worth pointing out. Though at the same time, what this ultimately translates to in terms of the human health span is more uncertain for calorie restriction than for exercise. See:
https://www.fightaging.org/archives/2010/03/exercise-and-life-expectancy.php
https://www.fightaging.org/archives/2011/08/quantifying-the-benefits-of-modest-exercise.php
Do you have a picture of Mr Delaney to show?
"That would require an unrealistically long study."
If they started a watched study from scratch, yes, but a survey with self-reporting of calorie consumption over a lifetime, despite the many faults and approximations in such a method, could yield statistically significant results (or a lack of them).