LONGECITY

When should a 16-year old start CR? I've also stopped eating sweet things a long time ago after learning that worms live longer if they avoid sugar (I think it was Cynthia Kenyon's research. Should I avoid carbs and mildly sweet foods entirely?

mid-late 20s

but it would be very helpful to start living a super healthy lifestyle now. (plant based food, sun avoidance, read lots)

Not everyone agrees that CR and avoiding sugar/carbs is a good thing. If you want to learn about an alternate view, Matt Stone brings some interesting points to the table. Here is a video he posted to youtube earlier this month:

http://www.youtube.com/watch?v=DKhX6Adf618

I follow his blog. Here is something he wrote a month or two ago:

The Calorie Restriction Myth

1) The only people successful at permanently reducing calorie intake by at least half are those that develop an eating disorder (and dieting at a young age is the top “risk factor” for developing an eating disorder), the deadliest known psychological disease that affects 11 million Americans alone, mostly young women – and globally has killed more people than the Holocaust.

2) Humans are surrounded by endless abundance and temptation for food, and with real people in the real world, cutting calories by half leads to massive rebound hyperphagia (pigging out – as is seen in yo-yo dieting and every human calorie-restriction trial ever conducted).

3) Calorie restriction experiments are done with animals from birth. This is a hugely significant difference, and the bodies’ of the creatures can develop at a rate that makes the low calorie intake sufficient – but this calorie intake is insufficient and causes rapid degeneration when the calorie level is cut after adulthood has already been reached. Comparing calorie restriction from birth to calorie restriction begun in adulthood is a completely invalid comparison.

4) Calorie-restricted laboratory animals display many characteristics of neurosis, anxiety, and social/behavioral disorders (like those with eating disorders). Thinking that cutting calories will lead to a long and prosperous life in a human is total fantasy that ignores what science and real world observation has already shown us.

5) A laboratory is a sterile environment, and even if the calorie restricted animals lived longer and did have a verifiably slower metabolic rate (pound for pound I don’t think they do), it’s hard to compare this to the real world. The real world is filled with opportunistic organisms and other pathogens, and a high metabolism controls the strength of the immune system completely. A high body temperature – a result of a high metabolism, protects from invasion just like a fever wipes an infection out. More importantly, it is obvious when looking at the real world what happens when food becomes scarce – famines lead to widespread disease and infection at astronomically higher rates. Of course, the body of research connecting degenerative disease like many autoimmune diseases and cancers to various infections is growing rapidly.

Guinevere, I'm close to Forever21 on this. I'd push the age down a bit, maybe early-mid twenties. In the meanwhile, I'd follow a Paleo diet. Mostly vegetables and meat; little or no grains. I'm agnostic on dairy; not technically paleo but too good to give up. Raw is good when you can do it.

I don't think that Matt Stone has a very good understanding of the correct practice of CR. He sounds like he's arguing against CR done wrong.

I probably wouldn't start it till late 20's. Plus, by then, we'll have better research and we'll probably know more about whether it's even worth it. In the meantime, I'd recommend you eat a healthy diet. Learn all you can about diet and nutrition, and challenge everything till you get answers. I like Stephan Guyenet's Whole Health Source blog, Kurt Harris' Archevore, Chris Masterjohn's The Daily Lipid, and Paul Jaminet's Perfect Health Diet. They all have slightly different takes on nutrition, but you have to read and make your own decisions. I would personally recommend a paleoish diet with meat, mainly ruminants, fish and definitely include shellfish, vegetables, starchy tubers, fruit, and maybe some grassfed dairy.

By the way, I"m almost 16 so about in the same boat.

Not everyone agrees that CR and avoiding sugar/carbs is a good thing. If you want to learn about an alternate view, Matt Stone brings some interesting points to the table.

A better question is whether one wants to learn about a credible or informed alternative view, of which Mr. Stone's is not an example.

Here is something he wrote a month or two ago:

The Calorie Restriction Myth

1) The only people successful at permanently reducing calorie intake by at least half are those that develop an eating disorder (and dieting at a young age is the top “risk factor” for developing an eating disorder), the deadliest known psychological disease that affects 11 million Americans alone, mostly young women – and globally has killed more people than the Holocaust.

Oh, my goodness gracious me.

First, who the heck is talking about "permanently reducing calorie intake by at least half"? I don't think ANYONE is suggesting that humans should cut Calories in half, and only a handful of rodent studies have even gone that far.

Second, and also in answer to Guinevere's question, no one is suggesting taking up CR "at a young age" like hers, so raising that is a complete red herring.

Third, multiple studies have addressed the relationship between CR and eating disorders, and the uniform finding in actual prospective studies is that neither conventional dieting for weight loss in the overweight (1), nor Calorie restriction per se(2), leads to ED. Yet people keep repeating the claim.

Fourth, the claim that eating disorders (which, again, CR is not, and does not predispose toward) are "the deadliest known psychological disease" is itself false, although there are certainly studies that seem to suggest that it is. The reason for this is that those studies look only at the mortality rate of anorexia patients that have already been hospitalized with the disorder. This, of course, grossly exaggerates the risk of the disease, just as it would grossly exaggerate the risk of death from heart disease if we assessed it by looking only at the mortality rate of people who had already been rushed into emergency after having suffered a heart attack or unstable angina.

Studies that instead look at the mortality rate of the general population of anorexics find the mortality rate to be similar to that of the general population, and perhaps lower (3-5) -- and much of that comes not from the risks associated with starvation or even micronutrient malnutrition, but from the associated psychological comorbidities, notably alcoholism, substance abuse, and suicidality.(5)

Fifth, it's true that ED "affects 11 million Americans alone," but most of these are disorders like bulimia which, while serious and psychologically traumatic, are far less dangerous to long-term physical health than anorexia. It's also true that ED, and especially anorexia, "affect ... mostly young women" -- because most of the less than 1.5% of adolescent girls that have anorexia (and cf. (6)) go on to grow out of it, making the numbers of adults with ED lower still. (Meanwhile, 2/3 of the US adult population is overweight, and a third are obese ... Priorities ...?).

"The Holocaust"?

2) Humans are surrounded by endless abundance and temptation for food, and with real people in the real world, cutting calories by half leads to massive rebound hyperphagia (pigging out – as is seen in yo-yo dieting and every human calorie-restriction trial ever conducted).

"Cutting Calories by half," again.

(3) Calorie restriction experiments are done with animals from birth. ... but this calorie intake is insufficient and causes rapid degeneration when the calorie level is cut after adulthood has already been reached. Comparing calorie restriction from birth to calorie restriction begun in adulthood is a completely invalid comparison.

Making up bullshit is what makes for completely invalid comparisons. First, no Calorie restriction experiments are done with animals from birth -- none, zero, zilch. Successful, life-extending CR can begin at the onset of weaning, and no earlier.

Second, and less trivially, multiple studies have demonstrated that CR not only works, but works in direct proportion of remaining life expectancy, when initiated in early middle age (eg, (7)) or even early seniority (8) -- and see review in (9)). It is desperately tiresome to keep hearing people claim otherwise.

4) Calorie-restricted laboratory animals display many characteristics of neurosis, anxiety, and social/behavioral disorders (like those with eating disorders). Thinking that cutting calories will lead to a long and prosperous life in a human is total fantasy that ignores what science and real world observation has already shown us.

Nonsense all around: dieting and Calorie restriction lead to no psychological problems and may even have psychological benefits.(1,10,11) And, again, this is a red herring: eating disorders ≠ CR!

5) A laboratory is a sterile environment, and even if the calorie restricted animals lived longer and did have a verifiably slower metabolic rate (pound for pound I don’t think they do), it’s hard to compare this to the real world. The real world is filled with opportunistic organisms and other pathogens, and a high metabolism controls the strength of the immune system completely. A high body temperature – a result of a high metabolism, protects from invasion just like a fever wipes an infection out. More importantly, it is obvious when looking at the real world what happens when food becomes scarce – famines lead to widespread disease and infection at astronomically higher rates. Of course, the body of research connecting degenerative disease like many autoimmune diseases and cancers to various infections is growing rapidly.

Wow: there are some actual half-truths in there, instead of just complete, ignorant nonsense! He's right in thinking that CR does not reduce metabolic rate when adjusted for mass, as he's indicating: ie, a mouse or a person with lower mass inevitably burns fewer Calories than a mouse or a person with higher mass. But then he goes on blathering, completely ignoring his own vague admission, pretending instead as if metabolic rate is actually lowered in some meaningful sense that might have health implications.

And it does seem that the story on CR and the immune system is not the unvarnished good that it once seemed to be (see this post and this post). But "a high metabolism controls the strength of the immune system completely"?? What? Where does he come up with this crap??

"A laboratory is a sterile environment": no, it is not. Infections happen even in "specific pathogen-free" labs, and CR works even in the non-SPF labs of the earliest CR experiments. Yes, most CR studies TODAY take some steps to control pathogens, so that they don't lose animals to infection when they're looking for data in intrinsic aging process -- but of course, that's a very recent trend: there were no "specific pathogen-free" (SPF) vivaria in 1935 when Clive McCay was doing the early CR work at Cornell, and he cohoused his animals. In fact, it was still a novelty as late as 1982, when Yu et al reported that "there have been no studies on the effects of food restriction on the already long-lived barrier-maintained SPF rat populations" (12). So there were infections going 'round the lab in nearly ALL CR studies prior to that -- and the CR animals still lived longer (as they also say: Food restriction has proved to be the most effective and reproducible procedure in experimental gerontology for enhancing the longevity of laboratory rodent populations." (12)).

Second, even SPF conditions -- which are the standard TODAY, for the aforementioned reasons -- aren't actually totally germ-free environments: they're called 'specific' pathogen-free conditions because the weanling animals are guaranteed by careful long-term examination to be free of *specific* bugs, not absolutely everything (and which 'specific' pathogens can be, well, specified by the lab).

The "completely germ free" animal is a rarely-used protocol, in which animals are delivered via caesarian section instead of by the conventional route to spare them from the microbes in the vaginal tract as they leave the nearly antiseptic conditions of the womb, and then specially-husbanded to keep them away from future sources contamination (including putting them in the same positive air pressure differential "plastic-bag" housing used for bubble babies).

(13) actually studied the differential effects of conventional and germfree housing in CR vs AL rats -- and, surprise: the CR animals did the best, under both protocols.

(14), similarly, compared the effects of SPF and GF housing in CR and AL rodents, and found that "The mean life span of the full-fed SPF and GF mice was 75.9 and 88.9 weeks respectively, while the mean life span of the food-restricted SPF and GF mice was 117.5 and 109.6 weeks, respectively. Mice in both GF and SPF food-restricted groups were characterized by lower body weight and increased survival."

And finally, guess what the "body of research ... [on] autoimmune diseases and cancers" says about CR?

Come on, folks ...

References
1: National Task Force on the Prevention and Treatment of Obesity. Dieting and the development of eating disorders in overweight and obese adults. Arch Intern Med. 2000 Sep 25;160(17):2581-9. Review. PMID: 10999971 [PubMed - indexed for MEDLINE]

2: Williamson DA, Martin CK, Anton SD, York-Crowe E, Han H, Redman L, Ravussin E; Pennington CALERIE Team. Is caloric restriction associated with development of eating-disorder symptoms? Results from the CALERIE trial. Health Psychol. 2008 Jan;27(1 Suppl):S32-42. PubMed PMID: 18248104.

3: Iacovino JR. Anorexia nervosa: a 63-year population-based survival study. J Insur Med. 2004;36(2):107-10. PubMed PMID: 15301224.

4: Korndörfer SR, Lucas AR, Suman VJ, Crowson CS, Krahn LE, Melton LJ 3rd. Long-term survival of patients with anorexia nervosa: a population-based study in Rochester, Minn. Mayo Clin Proc. 2003 Mar;78(3):278-84. PubMed PMID: 12630579.

5: Sullivan PF. Discrepant results regarding long-term survival of patients with anorexia nervosa? Mayo Clin Proc. 2003 Mar;78(3):273-4. PubMed PMID: 12630577.

6: Bulik CM, Reba L, Siega-Riz AM, Reichborn-Kjennerud T. Anorexia nervosa: definition, epidemiology, and cycle of risk. Int J Eat Disord. 2005;37 Suppl:S2-9; discussion S20-1. Review. PMID: 15852310 [PubMed - indexed for MEDLINE]

7: Weindruch R, Walford RL. Dietary restriction in mice beginning at 1 year of age: effect on life-span and spontaneous cancer incidence. Science. 1982 Mar 12;215(4538):1415-8. PubMed PMID: 7063854.

8: Dhahbi JM, Kim HJ, Mote PL, Beaver RJ, Spindler SR. Temporal linkage between the phenotypic and genomic responses to caloric restriction. Proc Natl Acad Sci U S A. 2004 Apr 13;101(15):5524-9. Epub 2004 Mar 25. PubMed PMID: 15044709; PubMed Central PMCID: PMC397416.

9: Rae M. It's never too late: calorie restriction is effective in older mammals. Rejuvenation Res. 2004 Spring;7(1):3-8. Review. PubMed PMID: 15256039.

10: Redman LM, Martin CK, Williamson DA, Ravussin E. Effect of caloric restriction in non-obese humans on physiological, psychological and behavioral outcomes. Physiol Behav. 2008 Aug 6;94(5):643-8. Epub 2008 Apr 18. PMID: 18502453

11: Inoue K, Zorrilla EP, Tabarin A, Valdez GR, Iwasaki S, Kiriike N, Koob GF. Reduction of anxiety after restricted feeding in the rat: implication for eating disorders. Biol Psychiatry. 2004 Jun 1;55(11):1075-81. PMID: 15158426 [PubMed - indexed for MEDLINE] 12: Yu BP, Masoro EJ, Murata I, Bertrand HA, Lynd FT. Life span study of SPF Fischer 344 male rats fed ad libitum or restricted diets: longevity, growth, lean body mass and disease. J Gerontol. 1982 Mar;37(2):130-41. PMID: 7056998

13. Snyder DL, Pollard M, Wostmann BS, Luckert P. Life span, morphology, and pathology of diet-restricted germ-free and conventional Lobund-Wistar rats. J Gerontol. 1990 Mar;45(2):B52-8. PubMed PMID: 2313040.

14: Tazume S, Umehara K, Matsuzawa H, Aikawa H, Hashimoto K, Sasaki S. Effects of germfree status and food restriction on longevity and growth of mice. Jikken Dobutsu. 1991 Oct;40(4):517-22. PubMed PMID: 1748169.