TomBAvoider Report post Posted September 28, 2017 Nice to hear from you, Dean. I don't want to impose on your posting semi-retreat, so feel free to answer or not, but I'm curious as to whether you've moderated your exercise just based on the knee feedback or whether it's the result of much bigger re-evaluation of the pro/cons of exercise. FWIW, I'm curious, because I've done a lot of thinking/stewing about exercise and decided that I should cut back from my current 4 a week, 50 minute each, jogging sessions. I've been mulling it over, but have not pulled the trigger yet. All the best! Tom Share this post Link to post Share on other sites
Dean Pomerleau Report post Posted September 29, 2017 Tom, My decision to cut back on the amount I exercise was based solely on feedback from my body. --Dean Share this post Link to post Share on other sites
TomBAvoider Report post Posted September 29, 2017 Thanks, Dean! Share this post Link to post Share on other sites
VeganCarbSmart Report post Posted September 29, 2017 (edited) Hi VeganCarbSmart, <snip> Yes I'm still around. I have cut back on my exercise, especially the biking, since (as you suggest) I was starting to feel it in the knees. These days I'm jogging a little over one (hilly) mile, resistance training for about 30 minutes, casual (stationary) biking for 30-60min, and walking ~3 miles each day. Little has changed in my diet except I'm eating less (with less exercise) and I dropped the durian (too expensive to justify). I'm still eating only a single meal each day in the early morning consisting of vegetables, fruits, nuts, seeds, and a small portion of my 'starch mix' - legumes, sweet potatoes, barley & rice. I've moderated my weight somewhat - I'm now 135lbs (BMI = 20.0). Hey Dean, I've just got to say that if Dr. Walford is "out there" and could know this, then he's smiling and extremely pleased with where you're at right now. You can attract far more people to this lifestyle with what you're doing now combined with your past experience at being at the extreme with more health vulnerabilities put at risk. I'm sure you know to keep your cycling rpm above 90 and/or at very low resistance in order to preserve your joints long-term. 1) Now that you've had your exercise bike for over a year now would you still recommend this same model or try something else? 2) I guess you're trying to increase your BAT using cold exposure techniques too? I have not read that thread yet, but if anything has changed w/your experiments doing that please update us on that too. And, are there any methods or tests or markers to verify if it's working? 3) Have you posted your favorite Vegan related websites and YT channels that you follow somewhere "here" at CRS? I think it would be helpful to know, since you're so experienced with this diet long-term and continue to stay informed about it. Your opinions and commentary about any of these favs might be helpful too. Edited September 30, 2017 by VeganCarbSmart Share this post Link to post Share on other sites
chrysis10 Report post Posted May 30, 2020 Hello Mr. Pomerleau, Thank you for sharing so many details about your CRON experience. I did my best to follow CRON for a few years after my son was born, and I did really enjoy it - but that was 15 years ago now. I'm curious about muscle mass and your lower protein diet now than before. When you reduced your protein, did you find (either soon or much later) that it affected your muscle mass? At some point, did you add extra weight training to compensate? Or do you feel that the amount of protein you eat is adequate enough that you don't appreciate a loss of muscle -- if so, how did you determine the "right" amount of protein for yourself? If you have already responded to this question (and I just have not come upon it yet), I'd appreciate a link or a pointer to where I might find that. I'm very interested in changes, both positive and negative, to your body composition over the years; and what factors led to each. Sincerely, Karen C Share this post Link to post Share on other sites
Dean Pomerleau Report post Posted May 30, 2020 Hi Karen, Welcome to the CR Forums! Thanks for your questions. I'll try to answer them. 57 minutes ago, chrysis10 said: When you reduced your protein... Somewhere around 2005 - 2007. There is some discussion of my diet evolution earlier in in this very thread (which I'd forgotten!), but the best discussion of my protein history and motivation for reducing it can be found in the following discussion between Michael and me: The TLDR of the above thread is that back in the early days of the CR Society (early 2000s) both he and I used to eat a relatively high protein diet (~30% of calories - 30/40/30 "Zone Diet") until we participated in a human CR study by Luigi Fontana [1] which found that those of us who were following a high protein CR diet had a relatively high level of IGF-1, which has come to be though of as pretty pro-aging. For a discussion of the tradeoffs associated with high vs. low IGF-1, see this thread: Back to your questions: 57 minutes ago, chrysis10 said: When you reduced your protein, did you find (either soon or much later) that it affected your muscle mass? At some point, did you add extra weight training to compensate? Or do you feel that the amount of protein you eat is adequate enough that you don't appreciate a loss of muscle. I've never noticed that protein per se was a big driver of my muscle mass. When I went on CR in 2001, I dropped about 45 lbs (172 -> 127, BMI 25.8 -> 19.0). During that drop I lost quite bit of fat, as well as muscle and bone mass. It's just something I accepted. I've always done a modest amount of weight training, and haven't changed that in an attempt to maintain extra muscle. I consider my muscle mass sufficient for health purposes and enough to avoid late-life sarcopenia. Because I'm once again exercising an unusually large amount (after a drop for while in 2017), I eat a lot of calories and despite being a vegan, my protein intake is more than adequate - in the neighborhood of 100g / day. 57 minutes ago, chrysis10 said: how did you determine the "right" amount of protein for yourself? I've never worried about it beyond trying to keep my protein intake from being too high (see above threads). If I'm getting enough high-quality calories from a variety of (vegan) sources I figure I'm getting sufficient protein. --Dean ------------ [1] Aging Cell. 2008 Oct;7(5):681-7. Long-term effects of calorie or protein restriction on serum IGF-1 and IGFBP-3 concentration in humans. Fontana L(1), Weiss EP, Villareal DT, Klein S, Holloszy JO. Author information: (1)Division of Geriatrics & Nutritional Sciences, Washington University School of Medicine, St Louis, MO 63110, USA. lfontana@dom.wustl.edu Comment in Aging Cell. 2009 Apr;8(2):214; author reply 215. Reduced function mutations in the insulin/IGF-I signaling pathway increase maximal lifespan and health span in many species. Calorie restriction (CR) decreases serum IGF-1 concentration by ~40%, protects against cancer and slows aging in rodents. However, the long-term effects of CR with adequate nutrition on circulating IGF-1 levels in humans are unknown. Here we report data from two long-term CR studies (1 and 6 years) showing that severe CR without malnutrition did not change IGF-1 and IGF-1 : IGFBP-3 ratio levels in humans. In contrast, total and free IGF-1 concentrations were significantly lower in moderately protein-restricted individuals. Reducing protein intake from an average of 1.67 g kg(-1) of body weight per day to 0.95 g kg(-1) of body weight per day for 3 weeks in six volunteers practicing CR resulted in a reduction in serum IGF-1 from 194 ng mL(-1) to 152 ng mL(-1). These findings demonstrate that, unlike in rodents, long-term severe CR does not reduce serum IGF-1 concentration and IGF-1 : IGFBP-3 ratio in humans. In addition, our data provide evidence that protein intake is a key determinant of circulating IGF-1 levels in humans, and suggest that reduced protein intake may become an important component of anticancer and anti-aging dietary interventions. PMCID: PMC2673798 PMID: 18843793 Share this post Link to post Share on other sites
Mike41 Report post Posted May 30, 2020 1 hour ago, Dean Pomerleau said: Hi Karen, Welcome to the CR Forums! Thanks for your questions. I'll try to answer them. Somewhere around 2005 - 2007. There is some discussion of my diet evolution earlier in in this very thread (which I'd forgotten!), but the best discussion of my protein history and motivation for reducing it can be found in the following discussion between Michael and me: The TLDR of the above thread is that back in the early days of the CR Society (early 2000s) both he and I used to eat a relatively high protein diet (~30% of calories - 30/40/30 "Zone Diet") until we participated in a human CR study by Luigi Fontana [1] which found that those of us who were following a high protein CR diet had a relatively high level of IGF-1, which has come to be though of as pretty pro-aging. For a discussion of the tradeoffs associated with high vs. low IGF-1, see this thread: Back to your questions: I've never noticed that protein per se was a big driver of my muscle mass. When I went on CR in 2001, I dropped about 45 lbs (172 -> 127, BMI 25.8 -> 19.0). During that drop I lost quite bit of fat, as well as muscle and bone mass. It's just something I accepted. I've always done a modest amount of weight training, and haven't changed that in an attempt to maintain extra muscle. I consider my muscle mass sufficient for health purposes and enough to avoid late-life sarcopenia. Because I'm once again exercising an unusually large amount (after a drop for while in 2017), I eat a lot of calories and despite being a vegan, my protein intake is more than adequate - in the neighborhood of 100g / day. I've never worried about it beyond trying to keep my protein intake from being too high (see above threads). If I'm getting enough high-quality calories from a variety of (vegan) sources I figure I'm getting sufficient protein. --Dean ------------ [1] Aging Cell. 2008 Oct;7(5):681-7. Long-term effects of calorie or protein restriction on serum IGF-1 and IGFBP-3 concentration in humans. Fontana L(1), Weiss EP, Villareal DT, Klein S, Holloszy JO. Author information: (1)Division of Geriatrics & Nutritional Sciences, Washington University School of Medicine, St Louis, MO 63110, USA. lfontana@dom.wustl.edu Comment in Aging Cell. 2009 Apr;8(2):214; author reply 215. Reduced function mutations in the insulin/IGF-I signaling pathway increase maximal lifespan and health span in many species. Calorie restriction (CR) decreases serum IGF-1 concentration by ~40%, protects against cancer and slows aging in rodents. However, the long-term effects of CR with adequate nutrition on circulating IGF-1 levels in humans are unknown. Here we report data from two long-term CR studies (1 and 6 years) showing that severe CR without malnutrition did not change IGF-1 and IGF-1 : IGFBP-3 ratio levels in humans. In contrast, total and free IGF-1 concentrations were significantly lower in moderately protein-restricted individuals. Reducing protein intake from an average of 1.67 g kg(-1) of body weight per day to 0.95 g kg(-1) of body weight per day for 3 weeks in six volunteers practicing CR resulted in a reduction in serum IGF-1 from 194 ng mL(-1) to 152 ng mL(-1). These findings demonstrate that, unlike in rodents, long-term severe CR does not reduce serum IGF-1 concentration and IGF-1 : IGFBP-3 ratio in humans. In addition, our data provide evidence that protein intake is a key determinant of circulating IGF-1 levels in humans, and suggest that reduced protein intake may become an important component of anticancer and anti-aging dietary interventions. PMCID: PMC2673798 PMID: 18843793 All well and good but as I age I’m getting somewhat concerned about lower levels as this article points out: https://www.sciencedirect.com/science/article/abs/pii/S0197458014006952 Share this post Link to post Share on other sites
Ron Put Report post Posted June 2, 2020 It would depend how one defines "low levels of protein." I struggle to maintain my protein levels close to RDA and Longo-suggested levels and the average on my essentially vegan diet is 134% of RDA. This seems to be more than sufficient to maintain my muscle mass at a relatively high proportion, with moderate body weight exercise I do at home. I am focusing mostly on methionine and have been keeping it at about 0.9g, which for me is at 146% of RDA. Share this post Link to post Share on other sites
mccoy Report post Posted June 2, 2020 On 5/30/2020 at 9:11 PM, Mike41 said: All well and good but as I age I’m getting somewhat concerned about lower levels as this article points out: https://www.sciencedirect.com/science/article/abs/pii/S0197458014006952 We discussed the IGF-1 optimum at length, if I'm not wrong that's not a free article and we cannot see any graphs with proposals of optimum IGF-1 concentrations. Share this post Link to post Share on other sites
Dean Pomerleau Report post Posted June 2, 2020 1 hour ago, mccoy said: if I'm not wrong that's not a free article and we cannot see any graphs with proposals of optimum IGF-1 concentrations. Sci-hub is your friend :-). Here are the tables from the paper in question [1]: The p-values are impressive in Table 2 due to the large number of people in the study (n=3355). But the magnitude of the difference in cognitive test scores between quartiles of IGF-1 appear quite small relative to the within-quartile variance. For example, look at the TMT-B test I've highlighted. The difference in average test score between the top and bottom quartile is ~5.5, but the within-quartile range is around +-15, indicating there is much more variation within quartiles than between the various quartiles of IGF-1. This suggests to me there are likely several factors that potentially contribute to having a low IGF-1. The speculation is that like with another growth-promoting hormone testosterone, there may be benign and potential even health-promoting reasons for having low IGF-1 and there may be other reasons that are associated with (or casually responsible for) poor physical and/or cognitive health - hence the wide within-quartile variance. But it is a speculation which we've discussed many times before in threads focusing on the potential pros and cons of high vs. low testosterone and/or IGF-1 including the ones I linked to in the post above. --Dean ----------- [1] Neurobiol Aging. 2015;36(2):942‐947. doi:10.1016/j.neurobiolaging.2014.10.035 Association of insulin-like growth factor-1 with mild cognitive impairment and slow gait speed. Doi T, Shimada H, Makizako H, et al. Abstract The decrease in serum insulin-like growth factor-1 (IGF-I) with aging is related to the neurobiological processes in Alzheimer's disease. IGF-1 mediates effects of physical exercise on the brain, and cognition has a common pathophysiology with physical function, particularly with gait. The aim of this study was to examine whether mild cognitive impairment (MCI) and slow gait are associated with the serum IGF-1 level. A population survey was conducted in 3355 participants (mean age, 71.4 years). Cognitive functions (attention, executive function, processing speed, visuospatial skill, and memory), gait speed, and demographic variables were measured. All cognitive functions and gait speed were associated with the IGF-1 level (p < 0.001). The association of IGF-1 with slow gait was weakened by adjustment for covariates, but MCI and the combination of MCI and slow gait were independently related to the IGF-1 level in multivariate analysis (p < 0.05). Our findings support the association of a low IGF-1 level with reduced cognitive function and gait speed, particularly with a combination of MCI and slow gait. PMID: 25467636 Share this post Link to post Share on other sites