I know someone that has 9-7% body fat and if muscles are not pumped and body is relaxed it looks strikingly normal and just fit.
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Agreed. Few can stay at that level without some disruption to their endocrine function. Is he also on TRT?
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Bryan is! 2mg patch daily. From Blueprint website.
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Meh… How can a protocol be optimal if you need to take exogenous testosterone? He would be banned from any athletic competition…
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btw @Maveric78 what are your T levels? You can do just so much to improve endogenous testosterone production at his/mine/your age. Do you have any recommendation except the working out/keeping BF percentage below 15%, good sleep…?
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16.1 nmol/L (464 ng/DL) in the last test so not high.
I’ve found hard aerobic training pushes it down if anything.
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I’m doubtful that long-term calorie restriction and super low body fat % is optimal.
Look at Michael Lustgarten, who’s 50, has 12.9% body fat and his blood biomarkers are excellent. He did say that he would experiment with lower body fat %. But he would not go lower if the biomarkers get worse. It’ll be interesting to see the results of his experiment.
Personally, I think the optimal body fat % for men is probably 10% to 15%.
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From the gene expression/long genes perspective only a level of fat which has an effect on gene expression would be material. High glucose levels inhibit HIF 1 alpha that would reduce autophagy hence it would undermine mitochondrial efficiency. Also individuals have a tolerance to glucose depending upon the state of their pancreas (which then impacts glucose levels).
Hence probably really low fat levels don’t have that much of a broader effect benefiting the phenotype.
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Many would disagree! I think this is the most studied phenomenon in promoting longevity.
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I think there is a big difference between:
- going from “eating too much” to “eating just right” and
- going from “eating just right” to “eating too little”
#1 has clear benefits and the benefits of #2 may be doubtful. I suspect that a lot of the animal studies are really #1 rather than #2.
Plus, there are major differences between lab animals and humans that make the applicability of animal studies to humans questionable.
For example, mice have a significantly higher metabolic rate than humans and therefore any reduction in such rate (from eating less) would have a much greater effect on mice than on humans.
There’s no question that “eating too much” is bad. But “eating too little” is also bad. How much one is eating can be approximated by one’s body fat %. Everything is a U shaped curve and the question is where is the bottom of U. I don’t believe that 7% body fat is the bottom of U. I think it’s probably somewhere between 10% and 15% for men.
For the vast majority of people, as evidenced by the obesity epidemic, doing #1 would absolutely improve their health. However, for those people who already have the optimal body composition (sadly, very few people have that), whether eating less and lowering body fat % further will provide more benefits is doubtful.
I think Bryan Johnson is eating too little, but only time can tell. He did say in an interview that he felt hungry all the time. I don’t think feeling hungry all the time is the way to live.
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It’s because of caloric restriction he needs to take testosterone.
It’s not like he’s blasting testosterone levels that athletes would use, he’s in the range of a 40 yr old.
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I don’t really think you are right. Almost all studies on human longevity diet found some sort of caloric deficit if I am not mistaken and just a quick google search provided with this study
https://www.science.org/doi/10.1126/science.abg7292
I don’t know how relevant this is, but my personal experience of being in caloric deficit for prolonged period does not affect weight or body composition that much or just to a certain point. I am in continuous caloric deficit of around 20% since more or less 6 months and my body weight is more or less constant and body fat percentage is around 14%, but that is probably cause I have low T levels and would need to supplement to go lower and probably train harder. At the beginning I have seen major changes, but only for a two or three months and from that on it has been stable (weight and composition). Everything stabilized at BMI 21,5. Started with BMI of 22,5 so not a big change. Me personally I think around 10% BF is great, I think going lower you need to train quite hard and have good T levels. I remember reading somewhere a while ago that major consequences for health start below 6%.
As much as I know caloric restriction improves T levels in overweight men and does not affect it in normal weigh men. There are some studies that show that, but meta analysis did not find any significant correlation even though 2 studies included in the systematic review (but not the meta-analysis) that found that calorie restriction reduced testosterone levels in athletes.
What I’m saying is that “calorie restriction” in humans is perhaps #1 and not #2. I get a sense that people are taking the concept too far, in the case of Bryan Johnson, which may be doing more harm than good.
My guess is that centenarians are probably lean, but I doubt that the male centenarians have 7% body fat.
If you are in a “calorie deficit,” then your weight will decrease. If your weight is stable, then you’re not in a calorie deficit, you’re at calorie maintenance, which is the amount of calories required to maintain your current body composition/weight. You will need different calorie amounts to maintain different body compositions/weights.
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The study says it differently:
Significant increases in total testosterone concentrations were reported in 3 of 4 studies in which CR was examined with overweight or obese men, compared with the control groups. Significant decreases in total testosterone concentrations were reported in 2 of 3 studies in which the effects of CR were examined with normal-weight, healthy men, compared with the control groups.
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I said it is my personal observation, I was quite meticulous (my husband would say obsessive) with my calculations. It is not proof, but body will adapt I guess. Even Bryan Johnson is in caloric deficit all the time and is maintaining weight.
must have been reading it too quickly, but this is the postscript of the analysis… these studies were not included in the meta analysis probably for some reason (validity?)…
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There appears to be a confusion of these two terms: “calorie deficit” and “calorie restriction” are not the same thing.
Bryan Johnson practices “calorie restriction,” which means that he’s eating less than what his body wants him to eat, but he’s at “calorie maintenance” assuming his weight is constant. If he’s not at calorie maintenance, and in a calorie deficit, then he will continue to lose weight, which I don’t believe is happening. His current maintenance calorie is quite low, and therefore can only support a very low body fat %.
Bryan Johnson’s body is telling him to eat more as demonstrated by the constant hunger, but he chooses to ignore the signal.
Honestly, I think Bryan Johnson would be perfectly healthy at say 10% body fat and it would make him look younger than now as he would have more fat on his face. Despite his age reversal claim, many people say he doesn’t look young because he has so little fat on his face.
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Yes, I agree, 7% has in my opinion nothing to do with longevity itself but vanity and I even with 14% I think this is quite enough for myself.
Will look more into these two terms calorie restriction and deficit. Makes sense. Though if I am not mistaken Bryan uses term deficit in interviews. But I can be mistaken.
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If he uses the term deficit in interviews he is mistaken. If you have a calorie deficit you don’t have enough energy to maintain your body in its current status.
I agree entirely with Kandice’s analysis on this.
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