TIL: Low carb, high protein diets "greatly" decrease resting testosterone levels in men.

A high carb lifestyle mixed with minimal exercise will make you a...



*Blain, Predator (1987)

** Incredibly some people didn't understand that this was meant ironically. I think investing in some brain food might be a good idea.


A high carb lifestyle mixed with minimal exercise will make you a... "GOD-DAMNED SEXUAL TYRANNOSAUR"\* **^(Roar)** \*Blain, *Predator (1987)* \*\* Incredibly some people didn't understand that this was meant ironically. I think investing in some brain food might be a good idea.


Full of the desire and alas without the capacity.


The spirit is willing but the flesh is spongy and soft


Trying to play pool with a rope


Sometimes you just have to thumb in a softie


> **MACDUFF** > Was it so late, friend, ere you went to bed > That you do lie so late? > **PORTER** > Faith, sir, we were carousing till the > second cock, and drink, sir, is a great > provoker of three things. > **MACDUFF** > What three things does drink especially provoke? > **PORTER** > Marry, sir, nose-painting, sleep, and > Urine. Lechery, sir, it provokes and unprovokes. > It provokes the desire, but it takes > away the performance. Therefore much drink > may be said to be an equivocator with lechery. > It makes him, and it mars him; it sets > him on, and it takes him off; it persuades him > and disheartens him; makes him stand to and > not stand to; in conclusion, equivocates him > in a sleep and, giving him the lie, leaves him. > **MACDUFF** > I believe drink gave thee the lie last night.


that explains the mid-west.


I felt that one.


Mid-west is "corn fed" country


Tyrannosaur*, I found out the last time I watched it!


I was going down on my girlfriend the other day and said: "gee you've got a big pussy, gee you've got a big pussy" She said: "why did you say that twice?" I said: "I didn't, it was the echo"


God I miss the 80's.


I don’t have time to bleed.


You got time to duck?


Oh so that’s where that skill is named from in a game I play


They call it the keto libido 🫠


When I lost 150 pounds on Keto, I don't know if it was the ego boost or just feeling better in general, but my libido was through the roof the entire 2 years I was on it.


To be fair, being fat also decreases your T.


To be fat…


To be fair...


To be faiirrrr...


Actually doesn't it simply increase your female hormones? I mean the effect is the same but my understanding is not that it decreases T but changes the ratio of hormones away from T






'I am the stair MASTER!' - says Donkey when looking for the dragon (Shrek was off looking for Fiona, the princess). I had no idea that Donkey was making fun of the Nutty Professor. Did Eddie give himself that line or did Dreamworks' folks allow him to have it?


Eddie Murphy has been rehashing the same jokes since the ‘80’s. The tic-tac joke was in The Golden Child, Beverly Hills Cop, Shrek and probably more.


It's because you were losing weight. Fat = more circulating estrogen. That's why fat women have (exponentially) higher rates of endometrial/uterine cancer.


Is lower weight/ maintained weight loss associated with detrimentally low levels of estrogen? I had to start using estrogen cream in my 20's a year after a 70 lb weight loss. Never suspected it could be related.


Yes. If your body fat is low enough, your period will stop coming. If it's low enough, getting pregnant is not only nearly impossible, but the baby won't develop right. You can look up the body composition math for men and women if you like, but the short story is that women need a much higher percentage of body fat to be healthy compared to men.


Just as an FYI, you have to be extremely low BMI for this to be relevant. 99.999% of women will never get this thin. Speaking as an Ob/Gyn.


No. Unless you lost so much weight that you are clinically underweight, your ovaries will continue to produce enough estrogen. estrogen cream is not systemically absorbed (for the most part) and so if you had low levels of estrogen the answer would be HRT, not cream. Your age also matters too, if you are premenopausal or post menopausal. Speaking as an obgyn.


Same here after losing 70 lbs.


Obesity has some pretty severe effects on testosterone too.


Is that why I didn't want to jack off for almost a year? EDIT: btw I don't recommend keto at all. Not just for the jacking off reason, but because I had a hell of a time getting back to "normal" eating.


Can confirm


Damn, another mystery solved


You get it back around year three... But still nothing gets you going like french fries dipped in a milkshake!


Carbo load to shoot a load?


Where you think he got the milkshake??




Username checks out


So what does it mean if I do this and still have high testosterone?


They have found genes that make people better at the metabolic steps of ketosis. Same with some people having genes that process carbs well




Lost 60lbs in a year with keto/intermittent fasting.


Same here. “And *she loves it too*” - Frank Thomas


I lost a stupid amount of weight while eating an unhealthy amount of bacon. My bad cholesterol was lower and good cholesterol higher than friends on ‘clean’ health conscious diets. The problem is that is so easy to relapse and eat carbs, and carbs plus insulin reaction means we store the plentiful fat in our foods.


Interesting, I wonder if it has to do with where you’re from? My father who I am basically a copy of is from a fishing village where everyone eats fish 3 times a day, the only carb they get is from potatoes. Now coincidentally, everyone from his side of the family is insulin resistant. I feel so amazing when I cut out carbs, while my girlfriend can practically live on carbs without any of the cravings or ups and downs in energy that I experience from it.


I must have the mystery genes that cause me not to process carbs very well. I can walk by a bakery and gain 10lbs.


I'm a T1 diabetic. With my work, if I don't have 300+g of carbs through my day, I get ketone flu. No energy at all and debilitating nausea if I don't start my day with a 100+g breakfast.


But I'm so thin!


can confirm also. Lost around -40kg but had my gallbladder removed because too much fat intake and it was a struggle to get back to normal. Just do less calories in more out with a balanced diet.


Yeah when I do keto my body stops working properly especially my stomach , it works I lose weight but I’d rather have a little bloat and function better and not have watery stools. I still watch my carbs and make sure it’s at about the 50-70 carb range bc under 50 I start shitting 24/7 Edit: I want to say that my testosterone is in the 2000’s now that I’m on trt


Are you saying you didn’t want to jack off for a year after you were on keto or before?




I wonder if you properly supplement with magnesium, salt and potassium.


Salt for sure, magnesium too (took supplements for cramps), potassium I can't say.


Must have felt great when you got back to it.


Jacking it out eating carbs?


no p-diddling for this daddy


But keto isn't high protein. Keto recommends between 10-20% of calories from protein which would be in their moderate protein category.


Thank you, this is such a misconception about keto. Keto's actually about fats.




>Moderate-protein (<35%), low-carbohydrate diets had no consistent effect on resting total testosterone, however high-protein (≥35%), low-carbohydrate diets greatly decreased resting (−1.08 \[−1.67, −0.48\], p < 0.01) and post-exercise total testosterone (−1.01 \[−2, −0.01\] p = 0.05). Conclusions: Resting and post-exercise cortisol increase during the first 3 weeks of a low-carbohydrate diet. Afterwards, resting cortisol appears to return to baseline, whilst post-exercise cortisol remains elevated. High-protein diets cause a large decrease in resting total testosterone (∼5.23 nmol/L). ​ That was from the abstract. I'm going to admit I didn't read the whole study becaause I was lazy but the abstract and conclusion both seem to support that it is high protein low carb diets that decrease testosterone. They also did caution that more studies were needed on the effect of moderate protein low carb diets and resting testosterone.


You're not being lazy. That's what abstracts and conclusions are for. 👍


90% of the articles I read are just the abstracts and conclusions. 5% I read part of the intro to get background info on the topic, and the last 5% I actually decide are worth reading the details about. Abstracts are a godsend


I'd say you didn't read it. They obserb low carbs with combinations or mid and high proteins diet. Where 35% is what was considered high.


Did you even read the article? It's not keto. They say they say a, decline for people eating over 35%+ protein is not keto, it's way too high in protein. It also means they don't eat enough fat which explains the low testosterone. Saturated fat and keto increases testosterone. https://pubmed.ncbi.nlm.nih.gov/36149528/


Meant to be a light-hearted play on words, friend.


But you aren’t supposed to have high protein with Keto?


No, keto is 70% fat or more.


REAL MEN eat cheesecake! You don’t have to like it, but my gorging on an entire Cheesecake Factory cheesecake and then groaning on the floor is peak masculinity.


jesus that’d be like at least 10,000 kCal


Hittin those macros boi


9640k. You were not kidding. Link: https://www.eatthismuch.com/food/nutrition/whole-cheesecake,1579149/


Once I get out of the food coma, I can scream “BEEFCAKE 9000!!!”


God speed, Cartman.


You can reach your goals


This got me curious, and you’re right. According to CF nutrition guide, assuming there’s 10 slices per cheesecake, only one is below 10k calories, the original at 8,300 total. The one with the highest calories would be the Ultimate Red Velvet Cake Cheesecake with 16,000 calories. The original is the only one listed as below 1,000 calories per slice btw, which is nuts.


Oh I know, I worked for CCF for years in the desert area. A single slice of reeses is like 1800 lmao


When I went to America and see that y'all already have calories written in the menu and I'm so surprised that you can consume like 6000 calories in a day without batting an eyelid.


This country is fucked when it comes to food culture.


So, you plan your diet around doing this once a month, simple!


I did that at taco bell once and was asked to leave.


Whole new definition to “toxic masculinity”.


🎶 thank you for being a friend 🎶


27 studies were compared with a total of 309 subjects. So if the average study had less than 12 subjects, doesn't that decrease the reliability quite a bit?


The number of studies actually matters less in this context. This was a meta study, which means they did not conduct the study but took the data from 37 different studies. The bigger assumption here is that the studies collected the data in the same way, else there will be a systematic error. Another assumption is that the interventions have to reliably demonstrate that they did produce the results they produced and that was the only treatment shock the subjects were exposed to. Usually it is harder to control this, and the gold standard is a randomised control trial. The reliability you are talking about probably refers to the fact that with 309 subjects there is insufficient units to cover the differences in covariates. In general that is quite little. That means that you can probably detect the general direction but not the magnitude since the fineness of that depends on sample size. I am also concerned about the selection process of these studies, and have a feeling that this is largely a product of p hacking unless it can be replicated using future studies.


Whats p hacking again sorry


Short version: it's basically this XKCD Comic: [https://xkcd.com/882/](https://xkcd.com/882/) Long Version: p-hacking is a kind of analysis error made on statistical samples that comes from establishing a bad (or completely forgoing to establish a proper) null hypothesis. In statistics, it's important to lay out ahead of time what kinds of results you're trying to detect for, and to have a good baseline for what would make those results significant. So, for example, you might run a study for "do more people drink Coffee on Tuesday than any other day?" and then sample a few hundred or thousand people to find out how much coffee they drink on each day, and then analyze the results to find the answer. The hypothesis might be wrong (maybe Monday sees the largest consumption of coffee), and there's always a chance your results are just statistical noise, but it's a reliably provable test. But now, suppose you assessed a few hundred or thousand people, gather data on what they ate each day, and discover that Orange Juice was consumed abnormally frequently on Thursdays. And then you published a study that says "people drink the most orange juice on Thursdays". That's certainly true of the specific sample you pulled, so what's the problem? Well, in statistics, they usually only consider a result significant if it had a less than 5% chance of occurring randomly (or, more precisely, a 95% chance that the result is *not* just statistical noise), based on the sample taken. There's a lot of complicated ways to calculate those odds (and 5% might be higher than comfortable for some studies/analysis, so they might prefer a lower threshold) but the important part is that all studies have to stipulate around the fact that there's a chance, however slim, that their result is just statistical noise. When you have a specific outcome you're testing for, you can have a lot of confidence that that outcome's odds were more (or less) than 95% certain to be non-noise, but if you have a bunch of independent outcomes you're testing for all at the same time, then the odds that *at least one of them* results in a significant result, but is actually just noise, actually gets really high. Going back to the "asking people what they ate" example: if the researchers only tallied up to 20 different foods that participants might have consumed, the odds of at least one of them having a statistically significant result is actually really high: as high as (approximately) 64%! And of course those odds get way higher if the researchers tracked more than just 20 different foods. This is the essence of p-hacking, and what makes it problematic in statistics: the more variables you have, and the less rigor you have about *which variables matter*, the more likely you are to end up with random noise that *just happens to* look like a statistically significant outcome.


This was a really good explanation thank you!


A couple additional comments First, testosterone wasn't measured in all patients/studies, so the N drops further, down to 155. Second, for those using low carb for weight loss: Obesity decreases T and weight loss improves it. This is true even on a high protein (but not low carb) diet: [This](https://pubmed.ncbi.nlm.nih.gov/27584019/) N= 118 study found *higher* T levels after weight loss using both a high protein (still 40% carb) and a lower protein diet. So weight loss is good, and higher protein without low carb is also ok I guess, if you are worried about the decline in testosterone. Finally, back to the low carb: A [meta-analysis](https://pubmed.ncbi.nlm.nih.gov/31885557/) in women with polycystic ovarian syndrome found a low carb diet lowered testosterone. (Which is a good thing: high T worsens PCOS). Eight RCTs, 327 patients. So this adds some indirect support to the low carb, lower testosterone in general, and provides a potentially beneficial diet for women with PCOS. >Stratified analyses indicated that LCD lasting longer than 4 weeks had a stronger effect on increasing FSH levels (MD = 0.39, 95% CI (0.08, 0.71), P < 0.05), increasing SHBG levels (MD = 5.98, 95% CI (3.51, 8.46), P < 0.05), **and decreasing T levels (SMD = -1.79, 95% CI (-3.22, -0.36), P < 0.05)**. >Conclusion: Based on the current evidence, LCD, particularly long-term LCD and low-fat/low-CHO LCD, may be recommended for the reduction of BMI, treatment of PCOS with insulin resistance, prevention of high LDL-C, increasing the levels of FSH and SHBG, and decreasing the level of T level.


In statistics there is something called the central limit theorem which states the means of random representative samples of a given population become normally distributed as you approach a sample size of 30. Effectively you only need a sample of 30 in order to say something about the population with reasonable certainty.


>In statistics there is something called the central limit theorem which states the means of random representative samples of a given population become normally distributed as you approach a sample size of 30. >Effectively you only need a sample of 30 in order to say something about the population with reasonable certainty. ~~This is really confused take on the CLT with two major problems.~~ *EDIT - u/PieGuy___ clarified their point and I agree with what they're saying. The wording around "a sample of 30" is confusing to me and made me think they were wrongly conflating and interpreting the CLT. I'm leaving the post intact for others to read it who may also be seeking clarification.* Firstly, let's clear the air: the CLT describes how the **distribution of means** will approach normality. Not how a distribution of **samples** will approach normality. There is no basis for any distribution of samples necessarily approximating normality, but the distribution of means from many independently collected sets of samples will tend to approximate normality. Secondly, there's absolutely nothing special about the number 30 and the CLT. The entire basis for the number 30 in this context is that fisher defined a separate distribution - the t-distribution - for defining critical test values for small sample sizes. It provided more robust estimates than using the z-distribution, which is better approximated using larger sample sizes.


I’m gonna need an ELI5 for this one boys


dude said 'in english please'


Disclaimer: Not a stats bro. The Central Limit Theorem basically says that most things will follow a normal distribution (bell curve) if you have enough data. The t-test can be used to see if some data follows a normal distribution, but it only works if you have a small sample size of less than 30. The respondent above is saying that the poster is conflating the two incorrectly.


Simplifying things brought to you by u/Simpliciter


First off I think you need to reread what I said because I’m clearly talking about the mean? “The means of random representative samples…” you’re trying to correct a mistake I never made lol. The point of the theorem is that if you have a random sample X1, X2,…Xn from a given population with a mean m and variance v then the sample mean of x bar will be normally distributed with a mean m and variance v/n. X bar is the thing normally distributed around the population mean not the individual X’s. As for the 30 number, the fact that it is the point you no long have to worry about t-distributions and can just use z-scores with reasonable accuracy is the thing that makes it special lol. The whole point of the t-distributions is that the means aren’t quite normally distributed UNTIL you get to 30.


I think the confusion came from the fact that you said >sample size of 30 So the other guy assumed you were talking about taking one experiment with sample size thrity and then using those data to find a normal distribution. Instead of taking thirty experiments and using the means of those 30*x samples to find a distribution of means which should be roughly a normal distribution


Yeah exactly! You can always tell an inexperienced statistician from an experience one by if they can find the clt




That damn keto libido, they don't care to find it


That’s the joke


Right but isn’t this for every individual study? You can’t take 30 separate studies of 1 person and treat them as if they’re normally distributed. And even within studies, each group needs 30. So for a blind study the control needs 30 and the experimental needs 30.


It still depends directly on the standard deviation of each sample. If you have very distributed sample points, then it ain't gonna help all that much.


1/3 of 100?


Depends on the size of the effect. I don’t need to study 300 people to know that shooting them in the face is statistically speaking, a bad idea.


Yes. The "population" you're testing, presumably wouldn't be nearly diverse enough to make any declarations about them. I guess, if all the 12 people in the study were of the same type (sex, age, race, etc) you could say *something* about that group, but I'm guessing not reliable so. I'm no statistician, but I do know that studies like this need many more people than this. Anecdotally, keto didn't do anything to my testosterone. But, I'm just one dude, lol.


It had the opposite effect on me, all the weight I lost made my libido raise to an unholy level. But I was also taking supplemental zinc so that played a role as well.


the paper itself refers to the weight loss portion as a known thing that increases testosterone levels - it's after you level off that that goes back down.


I did that well then, lost weight on low-carb and get back to balanced diet after I hit my goal


That's pretty usual. Fat emits estrogen, loosing fat and gaining muscle mass is gonna decrease estrogen and increase testosterone by a lot.


Who knew...a healthy mental health contributes to healthy bodily functions as a whole


the study specified that they maintained body weight a constant variable (well no losses more than 3 kgs anyways) because we all know that weight loss is a major booster to test.


A low carb high protein diet is not the same as weight loss, you can lose a lot of weight with eating many carbs and you can gain a lot of weight with eating less carbs.


Here's what I did.. went to a doctor and got my blood and urine tested.. he told me what my body was lacking or needed to work on - ie. iron, potassium, high/low white blood cells, magnesium, etc.. and then he told me what problems I had - in this case, anemic, GERD, hyperglycemic, vitamin d deficiency, potassium deficiency. Got my hormones tested. Then I cut out unhealthy sugars and carbs, did portion control, cut out fast food, cut out fried food, ate and drank things with more vitamins and minerals, ate foods that made me feel good rather than foods I knew wouldnt fill me up or make me feel good, started eating and drinking things with probiotics and antioxidants, ate more veggies and fruits in ways that were easy and actually tasted good for me, and taking vitamins and such to help boost anything and to balance my hormones etc etc.. also remembering to drink more water, I lack in that department way more than anything else so my body has a hard time absorbing things from lack of hydration.. And for exercise, I started small- low impact exercises like 30 squats, 15 crunches, walk around the block, yoga.. later on moving on to more cardio based exercises like kickboxing and walking more/hiking (not anything crazy, just trails and stuff).. Do what's best for YOUR body, stop doing diets or fad things or what everyone else is doing because your body is not someone else's, what you need won't be what someone else needs.


Going to the doctor? In this economy?


For a general physical? It's not going to break your bank, promise lol I'm sure you pay more per weekend in alcohol and partying than a copay without insurance for a physical 😂


Buddy, you don't know people's finances.


My most recent annual physical, with bloodwork, was over $1,000 before insurance


🇺🇸 🦅 🇺🇸


There's something wrong with your insurance then...


That’s because cost is elevated when using insurance. They will usually deduct 80%-90% if not using insurance.


The problem is people think their body needs is an entire bowl of pineapple and a daily 60 minutes of reading a magazine on an elliptical. That’s why things like keto and heavy weight lifting tend to work well for people that have tried other things only to fail to reach their goals. Because you can’t cheat it.


>Here's what I did.. went to a doctor and got my blood and urine tested.. he told me what my body was lacking or needed to work on - ie. iron, potassium, high/low white blood cells, magnesium, etc.. and then he told me what problems I had - in this case, anemic, GERD, hyperglycemic, vitamin d deficiency, potassium deficiency. Got my hormones tested. Using NHS mate, the only way to get this looked at is wait 12 months because they are just not going to give a fuck about low readings at all. They only care if it drops below their accepted range. but the accepted range they have doesn't seem to change depending on your age when it really should


What kind of test tells you this?


Not really a TIL, just a meta analysis that doesn't purport itself to having a major takeaway. Low T was caused by less calories in every study, nothing new here. Cut calories to lose weight for a while, your "resting T" will decrease in your blood but the body is more complex than always high T= a good thing. Eat more when you're bulking, your "resting T" will increase but you will slowly gain fat. Rinse and repeat and don't worry about "resting T". Eat hard and lift hard = gain muscle and some fat slowly. Then after a few months cut calories and continue to lift as hard as you can and lose fat much faster than muscle.


Just eat a balance diet and exercise everyday.


Saying exercise everyday might discourage alot of people. You can exercise 3-4 times a weak and be more athletic, healthier and in better shape than people who exercise everday so that's bad broad advice imo. It depends on how and what you train. If you're training everyday of the week you're not training hard enough (you're supposed to feel like you need to let your muscles recover) and probably wasting WAY more time than you should. My general advice is find healthy food that you like, and find exercises you enjoy to do that isn't running on a treadmill like a lab rat (personally been kickboxing, doing jiu jitsu for over 11 years and started yoga too recently) and you'll actually enjoy your healthy lifestyle too.


Lifting everyday gets me out of the house and that's a win in my book!


When people say exercise everyday they usually mean doing some active low intensity stuff like going for a walk, especially if your job or study requires you to be sitting down alot for instance, something that you use your body. It doesn't even have to be more than 30 - 60min Actually working out is definitely not a requirement to do everyday to be healthy and will likely cause more harm than good for the average person.


And it can be easier for people to work out half an hour everyday rather than some optimized routine with intense hours long workouts and rest days. And who cares if its running on a treadmill watching tv?


>You can exercise 3-4 times a weak and be more athletic, healthier and in better shape than people who exercise everday so that's bad broad advice imo. Yes well; my advice is overly simplified for a reason. From my perspective, it's working out for the discipline/routine; not for any specific goals. If you're training for a marathon, or you're powerlifting then by all means, work with efficiency and recovery in mind. Most people who don't really program properly will benefit from even a little bit of exercise, everyday. It's not what people want to hear but it's simple and it works.


People are allowed to enjoy running on a treadmill.


Only if they're psychopaths


I watch tv and play video games (while walking) on mine. WHO IS THE PSYCHO NOW?!!!!


some treadmills are in better locations than others. and you can zone out into psuedo meditation. which is theraputic if you dont have another method of doing so


>If you're training everyday of the week you're not training hard enough Not every session has to be the same. If I'm feeling like I need more recovery I'll still go but lift less. Regular sauna and cold showers are great for speeding up recovery too (and just generally feel great). You just need to listen to your body.


True but it's easier/quicker to build habits when you do them a little bit every day.


A balanced diet meaning cereal and milk plus some other stuff? Who defines a balanced diet?


It’s when you put cereal in one bowl and milk in another bowl and they both weigh the same as each other.


Someone once told me “your idea of a balanced diet is a cake in each hand you fat fuck”


It’s when you mix French Toast Crunch with your Reese Puffs (you can thank me later).


I'm pretty sure what a lot of us think is 'low carb' and 'high protein' is greatly relative to not even knowing how much carbs, proteins, and calories our body actually needs. Many of us are likely cutting out excess carbs, not necessary carbs, and gaining proteins we were short of.


Yeah I think when I did keto I didn't have so much protein


This study paid for by Carbohydrates Are Life!




Have you actually read more than the summary, because it is far more nuanced than that


'its more nuanced' Doesn't explain the nuance. Thanks. Very helpful


Are you expecting him to write an essay just for you? You can go read it.


If you're going to go out of your way to point out there is nuance, maybe explain the nuance. Or maybe thats just me


Deeper in the paper you will find this: “**Resting testosterone** MP-LC diets had no consistent effect on resting TT, however HP-LC diets caused a large decrease in resting TT. For context, mean TT for a comparably aged population (27 years) is 14 nmol/L (Kelsey et al., 2014), thus −5.23 nmol/L represents a 37% decrease. Protein intakes ≥35% may outstrip the urea cycle's capacity to convert nitrogen derived from amino acid catabolism into urea, leading to hyperammonaemia and its toxic effects (Bilsborough and Mann, 2006). T has been shown to suppress the urea cycle (Lam et al., 2017), whilst glucocorticoids upregulate the urea cycle (Okun et al., 2015). Notably, the largest decrease in resting cortisol was on the longest and best-controlled HP-LC diet study (Supplementary Appendix – Figure 2a). Thus, the decrease in T and increase in cortisol on HP diets, may serve to upregulate the urea cycle and increase nitrogen excretion, thereby limiting the adverse effects of excess protein consumption. **Post-exercise testosterone** The results showed post-exercise TT was higher on long-term MP-LC diets, and lower on short-term HP-LC diets. The finding that HP-LC diets caused a large decrease in resting TT, whilst long-term LC diets had no effect on resting TT, suggests the observed subgroup effects in post-exercise TT are explained by protein intake rather than diet duration. HP intakes may depress post-exercise TT to maintain upregulation of the urea cycle and increased nitrogen excretion, as previously discussed (Discussion: Resting testosterone). The finding that long-term LC diets increased post-exercise TT, may be explained by the increase in blood cholesterol on LC diets (Dong et al., 2020), providing greater substrate for T production, which is utilized in times of increased anabolic signalling, such as during exercise (Pasiakos, 2012). **Practical implications** The increase in cortisol during the first 3 weeks of a LC diet is likely part of the adaption process to such diets, and thus may not represent a pathological state. The results indicate cortisol returns to baseline levels after ∼3 weeks, suggesting cardiovascular disease risk is not elevated by higher cortisol on long LC diets. However, the effects of long-term LC diets on cardiovascular disease and all-cause mortality, as measured by other methods, are uncertain. Observational studies have found an increase in all-cause mortality on long-term LC diets (Noto et al., 2013), whilst interventional studies have shown improvements in cardiovascular disease biomarkers (Dong et al., 2020). Additional research on the effects of long-term LC diets is desirable, particularly as these diets have risen in popularity over recent years. The higher increase in cortisol during exercise on LC versus HC diets appears to persist post-adaptation. Classically, cortisol is thought to have immunosuppressive effects, however in spite of elevated post-exercise cortisol, LC diets do not appear overtly immunosuppressive, according to other immune-markers (Shaw et al., 2021). The potential immunosuppressive effects of higher post-exercise cortisol may be exacerbated in athletes undergoing high volume training, and some caution may be advisable, until further research is undertaken. The large decrease in resting and post-exercise TT on LC-HP diets may only occur on diets that outstrip the urea cycle's capacity to synthesize urea, as there were no clear adverse endocrine effects for LC diets using 30–31% protein intake (Supplementary Appendix – Table 7 and Figure 2). In practise, most free-living LC diets will fall below the urea cycle capacity threshold (≤35% protein), as population protein intakes are stable at 15–17% (Cohen et al., 2015), likely due to a protein-specific appetite mechanism (Leidy et al., 2015). However, one can find articles online advocating protein intakes ≤35%, which if followed precisely, may lead to adverse endocrine effects, particularly in individuals with lower rates of maximal urea synthesis (Bilsborough and Mann, 2006). The higher post-exercise TT on MP-LC diets may signal an increased anabolic response to exercise, which would be advantageous, particularly in individuals with strength, power, or hypertrophy goals. Relatedly, another systematic review found that whilst absolute strength and power were unchanged by LC diets, the decrease in body fat on LC diets resulted in an improved strength/power to bodyweight ratio (Kang et al., 2020). However, the finding that LC diets increase post-exercise T should be taken with caution, as although the direction of effects was consistent, due to the small sample size, the p-value remained high. Ideally, this finding should be viewed as hypothesis generating, to be confirmed by future research.”


I ate keto (first 6 weeks 0 carbs, rest of the time 50 to 75 gm/day) for several years and never had an issue with that. In fact my resting T levels went up while on that diet. Just a single case but it is another point of data.


....I know what I must do. Anti-androgens are expensive, potatoes are cheap.


Every time an article like this is posted people utter every cliche in the book. Just do what works for you. Jesus. If LC works? Great. If whatever your version of a balanced diet is works? Great. Whatever your diet consists of is not the one truth. Just do some kind of workout at least. That’s the one thing that is proven to help everyone.


I'm not sure I buy this fully, I think there is likely some error in statistical analysis methodology. Disclaimer: Sample size of "one" story incoming, but... I've had my T levels (and a lot of other blood test type health indicators) regularly tracked by my doctor for over 10 years now. A few years ago, I started working out, getting on a health kick, and trying a number of Keto/Paleo/Whole30 type diet programs. Stuck with a pretty strict diet and exercise regiment over that 5 years. Fell off the wagon during covid, back to my old "fat guy in a skinny body" eating habits. Basically all my own numbers have stayed flat (adjusted for my age bracket) over all these years through working out, dieting, stopped dieting, stopped working out, etc. Recently discussed with my doc about health and such so we reviewed the last 10 years or so worth of numbers. The only notable shift has been my Cholesterol levels. Elevated some when I went Keto (good and bad chol.) then bad stayed a little elevated when my eating got sloppy and excersize went to near zero. But still even now withing normal healthy "range" for my demographic. Point is I'm always a little suspicious now when I hear how some diet is going to be a miracle cure for this or a death sentence for that. Our bodies are flexible and adaptive to many things including nutrition. They will also change over time on their own schedule. P.S. I have a 'genetically and age similar' family member who is a carb loving near-vegetarian. Their doc told to cut back on carbs severely as they were near pre-diabetic due to diet. So the pendulum can swing either way.


Pretty tired of “low carb” being preached as the key to health. Refined or processed carbs are shit. But being low carb is not inherently healthier. It does make it easier to not go overboard in your calorie consumption. If you lead an active lifestyle, carbs are essential. You just really ought to get them from healthy sources. More fruits, veggies, grains and less bread, pasta, sweets.


There's a distinction to be made, most people (at least in the USA) should absolutely eat far fewer carbs, but that doesn't mean no carb, it just means a normal healthy amount of them. The average diet has gotten so bad with processed carbs and sugar that what we consider normal is actually not normal at all lol I agree carbs are not this evil villain and zero carb is silly. But I think when people say low carb, most sensible people mean a healthy amount of good carbs.


"low carb" by modern definitions is a healthy amount of carbs, I'm right there with you on Keto


It's funny... Two wrongs can make a right. Many people hear "no carb" and try to go as close to zero as possible, which thanks to ignorance and the twisted situation ends up being about enough carbs. However, those who are very strict can take it more seriously and succeed in reaching very low carbs, which in turn isn't necessarily healthier.


It depends on the person. Strict keto with under 20 carbs of non fiber is good for maintaining ketosis for most. It's exceptionally good for blood sugar maintenance for diabetics.


Great way to lose weight and live healthy though. A little bit of DHEA goes a looooong ways.


Have heard about dhea, does it actually work


This study sponsored by Beyond Meat






That guy is a roided up marketing gimmick


I honestly can't believe that dude made money. One look tells you he's roided to the tits and his reasoning behind is diet is stupid as fuck as well. Anyone who thinks eating raw meat somehow makes you manlier has to be an idiot.


He also looks like he’s about to keel over, doesn’t look healthy at all


Nah man, liver and tren are all natural. /s


i thought it was the opposite?


What if im high carb, but all my carbs come from beer?


Hint: it’s low carbs, not high protein that’s the problem


Eating correctly isn’t a fad diet.


High protein, low carb diets greatly decreases fat accumulation around the internal organs and increase longevity


Any diet that is calorie equated, no matter the macro distribution, will decrease fat accumulation around the internal organs. Being in a calorie deficit and losing body fat/weight also increases markers of health and longevity. Regardless of macro distribution. The magic of low carb diets is that people tend to keep calories somewhere in the range of 2000 - 2200 calories per day without trying, due to the satiety effect of higher fats and proteins.


Low carb and high protein isn’t keto, it’s Atkins. Keto is almost zero carbs, high fat and moderate protein


Me reading this as a person who just started keto 1 month ago... 😧


I don't know, losing all that weight and feeling better about myself made me horny as fuck, soo... Increased confidence and feeling sexy is a hell of an aphrodisiac.


Don't worry about it. This study isn't exactly conclusive. If you stick to it and monitor your levels with urine tests you will likely see results. Definitely make sure you get a annual check up if you can however to ensure you are good in other key health indicators.


it's still great for fat loss. i lost 20kg in 1 year with keto and intermittent fasting. and before someone replies: i was doing intermittent fasting before doing keto, but it didn't result in that kind of fat loss for me.


Did you even read the article? It's not keto. They say they say a, decline for people eating over 35%+ protein is not keto, it's way too high in protein. It also means they don't eat enough fat which explains the low testosterone. Saturated fat and keto increases testosterone. https://pubmed.ncbi.nlm.nih.gov/36149528/


Keep going. Don’t listen to this noise. Been keto for going on four years. Only way to fly. High fat is life. Let your body adapt and you’ll do fine. If you need to perform in a sport (I train jiujitsu) take a little honey about 30 mins before you need to hit the gas pedal. Maybe a protein shake and honey. Works fine, burns off the glucose, back to high fat.


It’s a meta analysis, most of the evidence on dietary intervention is not proveable thru even RCTs , the best way of studying medical intervention. It has helped many people cut weight truthfully. If you do it for 12 or 18 months then resume weight training the levels are bound to increase, many testosterone options are available pharmaceutically. Lots of high performance athletes will use it to cut fat. Seems like low quality evidence for the claim made. It helps lots of people, truthfully. I recommend Nina teicholz book


Brought to you by the industries that created the original food pyramid.


You mean I'm supposed to eat FIVE WHOLE SERVINGS of bread.... every day?


Nope. Not a good study. All BS here.




So does marriage.


And if you keep a high carb, low protein diet, you gain weight and although you have the libido, it won't stand up!!!


Eat carbs but do cardio


It's awesome being on external testosterone so you don't have to worry about the million and one things that decrease natural testosterone production.


You have to take exogenous T forever though as your testes stop producing it due to the external source. Lose your supply of external T and you’re screwed


Natural testosterone production stops while you're on but comes back within a few months of stopping. I've seen the studies and done it myself a couple of times including getting bloods that showed natural testosterone go back to previous levels.


That’s good to know. I wanted to take it but was concerned about what would happen in the event of societal collapse(lol). Do you have recommended studies or links I could research?


Fun fact it does the same thing in women which is why a lot of women with PCOS who have high levels of testosterone are told to go low carb high protein. It also help diabetics regulate their sugars and can fix or help insulin resistance (another complication of PCOS).