Does Keto Affect Sex Drive? What the Ketogenic Diet Studies Actually Show

Searching keto and sex drive? No trial measured desire as its main endpoint. What was counted is testosterone, and it moved with the weight lost more than with ketosis. In 7 studies and 230 people, total testosterone rose after a ketogenic diet in 111 people (2.86, 95% CI 0.95 to 4.77), more on very low calorie versions (6.75) than normal-calorie ones (0.98), and the rise tracked weight loss. Across 27 low-carbohydrate studies and 309 healthy men, high-protein versions lowered resting testosterone (-1.08, 95% CI -1.67 to -0.48). Desire itself was counted once, in 20 people with obesity on a supervised diet, where women's sexual function scores improved alongside 7.7 units of BMI lost.

Figures from Furini et al. 2023 (PMID 36149528), Whittaker and Harris 2022 (PMID 35254136) and Castro et al. 2018 (PMID 30241426). The first two are meta-analyses of small trials; the third has no comparison group.

Is it the keto, or is it the weight?

You typed keto and sex drive into a search bar because a forum said the diet raises testosterone, and that a bigger number on a lab sheet means more desire. The second step is the one nobody checks. Testosterone was measured in most of these studies. Desire was not.

In the 7-study meta-analysis the post-diet rise tracked weight loss (R squared 73.6, p under 0.001) and age (R squared 36.4). A review of 52 studies in men with obesity found that same mediator across every diet it examined: about 3 nmol/l per 10 kg of weight lost. That is a weight loss effect wearing a keto label.

Lean men on high-protein low-carbohydrate versions went the other way, and a commentary puts that drop at about 5.23 nmol/l above 3.4 g per kg of bodyweight per day.

No man in any of these trials was asked about desire, so pooled testosterone tells you nothing about wanting. If your number moved and you did not, why weight loss did not fix libido walks through the gap. Two more pages cover low libido in men and exercise and libido.

Testosterone, counted

Furini and colleagues (2023) pooled 7 studies, 8 trials and 230 people. Total testosterone rose after any ketogenic diet by a mean difference of 2.86 across 111 people (95% CI 0.95 to 4.77, p = 0.003). Very low calorie versions gave 6.75 (95% CI 3.31 to 10.20), normal-calorie versions 0.98 (95% CI 0.08 to 1.88). Only three studies enrolled men with overweight or obesity, pre-post designs were pooled, and meta-regression tied the rise to weight loss and age. The authors write that the studies lack data on the hormones of the brain-to-gonad axis, so no mechanism is settled.

La Vignera and Condorelli (2026) screened 52 studies in men with obesity and found the very low calorie ketogenic diet most consistent, with randomized trials reporting total testosterone up 1.5 to 3.0 nmol/l and weight loss mediating it at about 3 nmol/l per 10 kg. It is a narrative synthesis with no pooled effect size, and it was not registered before it began.

Cignarelli and colleagues (2023) gave 22 men with obesity 28 days of a supervised very low calorie ketogenic diet. Total testosterone rose 35 ng/dl at day 7 and 74 ng/dl at day 28, SHBG rose, and calculated free testosterone and LH stayed flat. Men who started in the hypogonadal range trended to a larger rise, +98.12 ng/dl. No control group, 22 men, 28 days.

Da Silva Schmitt and colleagues (2023) ran an open-label randomized trial of 18 hypogonadal men with metabolic syndrome. Three months of low carbohydrate raised the erection questionnaire score and lowered symptom scores (p under 0.001), with total and calculated free testosterone up against control. The abstract prints p values only, no means, no intervals.

The other side of the ledger: Whittaker and Harris (2022) pooled 27 low-carbohydrate studies in 309 healthy men and found high-protein versions, 35% protein or more, lowered resting testosterone (-1.08, 95% CI -1.67 to -0.48) and post-exercise testosterone (-1.01, 95% CI -2 to -0.01), with cortisol up 0.41 (95% CI 0.16 to 0.66) in diets under 3 weeks. Whittaker (2023), a commentary carrying no new data, draws the line at 3.4 g per kg of bodyweight per day, above which testosterone fell by about 5.23 nmol/l; average intake sits near 1.3 g/kg/day. Chen and colleagues (2023), an umbrella review of 23 meta-analyses, reported that the ketogenic diet can decrease total testosterone (random-effects p under 0.05) and raise cholesterol fractions, with no effect size printed and evidence rated generally weak.

A capsule shelf is a hard sell on numbers this mixed. Do testosterone boosters work looks at what those bottles have done.

Free hormone, the part the forum skips

The gap between a lab sheet and a body has a name: sex hormone binding globulin, the protein that carries testosterone. It rises on this diet.

Svart and colleagues (2024) ran two randomized crossover trials. In the diet study, 11 middle-aged people with obesity, five of them men, did three weeks of a ketogenic diet against three weeks of a standard diet. Total testosterone was unaffected in men (20.2 against 18.2 nmol/l, p = 0.1) and lower in women (0.87 against 1.1 nmol/l). SHBG rose in men (31.2 against 25.0 nmol/l) and women (26.5 against 24.2 nmol/l), and the free androgen index fell in both, as did the free estradiol index. The other trial gave ten healthy young men one weight-adjusted ketone ester dose: testosterone went from 23.8 to 22.3 nmol/l, a difference that was not significant (p = 0.06). Eleven people in the diet study, and the authors say the clinical impact of the fall is still to be investigated.

The same split sits inside the 28-day trial: total testosterone up 74 ng/dl, SHBG up, calculated free testosterone and LH flat. Lima and colleagues (2026) reviewed 7 studies of a normal-calorie, normal-protein ketogenic diet lasting 4 to 24 weeks and found oscillation across gonadal hormones with no pooled effect size at all; women with PCOS showed lower testosterone and a better LH/FSH ratio.

In lean lifters it stays mixed. Paoli and colleagues (2021) followed 19 competitive natural bodybuilders for two months: body fat fell on the ketogenic diet, strength rose the same in both groups, and testosterone was measured with no value printed in the abstract. Wilson and colleagues (2020) found total testosterone up 118 ng/dl over 11 weeks in 25 resistance-trained men against -36 ng/dl on a western diet, with equal strength gains and no sexual measure attached.

Total testosterone can rise while the free fraction stays flat or falls. If your labs read normal and you still feel flat, normal labs, low libido is the closer read.

Women, and the one study that counted desire

Castro and colleagues (2018) followed 20 people with obesity, 12 of them women aged around 47, through four months of a very low calorie ketogenic diet, a medically supervised protocol, with visits at baseline, maximum ketosis, reduced ketosis and endpoint. Each person was their own control. They lost 7.7 units of BMI and 18 kg of fat mass, 1.2 kg of it visceral, and food craving scores, physical activity, sleepiness, quality of life and female sexual function scores all improved.

That is the only sexual-function outcome in this literature. Scoring was done in women, no comparison diet ran alongside it, two authors took advisory board fees or research grants from the diet's manufacturer and one is that company's medical director, and no separate desire figure is printed.

The hormone side is more consistent in women with PCOS. Paoli and colleagues (2020) followed 14 overweight women for 12 weeks: weight fell 9.43 kg, LH, total testosterone, free testosterone and DHEAS fell, SHBG and estradiol rose. Khalid and colleagues (2023) pooled trials of 45 days or more: free testosterone d -0.223 (95% CI -0.328 to -0.119), SHBG d 9.086 (95% CI 3.379 to 14.792, a wide interval), weight d -11.56. Zhang and colleagues (2019) pooled 8 randomized trials in 327 women: BMI SMD -1.04, insulin resistance -0.66, and past four weeks total testosterone SMD -1.79 (95% CI -3.22 to -0.36) with SHBG up.

The newest reviews hedge. Arsenaki and colleagues (2026) pooled 10 studies: weight -10.77 kg, LH down, androgen results inconsistent, heterogeneity high. Cannarella and colleagues (2025) found two randomized trials where these protocols did not beat a low-calorie diet on body weight.

In women with PCOS the hormone picture improves, and the one desire score ever counted rose with the weight in a study with no control group. Wider reading: PCOS and low sex drive and low libido in women.

What moves it

Weight lost is the lever every rise tracked: R squared 73.6 in the meta-analysis, and about 3 nmol/l per 10 kg across the 52-study review.

Protein pushed the other way above roughly 3.4 g per kg of bodyweight per day, a cut-off a commentary proposes from pooled small trials. Average intake sits near 1.3 g/kg/day.

The first three weeks carry a cortisol rise (0.41, 95% CI 0.16 to 0.66 in healthy men) that longer diets do not show. Supervision matters too: the biggest moves came on medically supervised very low calorie protocols, the 28-day trial and the four-month diet holding the only desire score. That is a protocol your doctor runs.

Two looser strands. Corsetti and colleagues (2023) gave 50 subfertile men a low-carb organic Mediterranean plan for three months and reported testosterone up, with no control group and no numbers printed. Liu and colleagues (2026) offer a mechanism as a hypothesis, more cholesterol available as a precursor for testosterone synthesis, with no pooled data behind it. Santos (2017) is a commentary that only asks the cholesterol question.

Sleep does more work on desire than any of this: sleep, libido and testosterone.

What has been counted, in order

Nobody ran a trial where desire was the thing being measured. That is the honest starting point for keto and sex drive. What these studies counted is testosterone, SHBG, cortisol, and in two cases a questionnaire about erections or overall sexual function. Seven looks sit between 2018 and 2024, and they point in more than one direction. Read them in order and the pattern is boring in a useful way: the hormone moves with the weight, and the wanting stays mostly unmeasured.

What actually helps, graded honestly

The weight you lose is the lever that was counted. Furini and colleagues (2023) pooled 7 studies and 230 people and found total testosterone up 2.86 (95% CI 0.95 to 4.77, p = 0.003), then tied that rise to weight lost in a meta-regression (R squared 73.6, p under 0.001). La Vignera and Condorelli (2026), reviewing 52 studies, put it near 3 nmol/l per 10 kg lost. Any diet that produces that weight moves the same hormone.

Protein kept under the line avoids the counted fall. Whittaker (2023) names 3.4 g per kg of bodyweight per day as the cut-off above which men's total testosterone dropped by about 5.23 nmol/l. Average intake sits near 1.3 g/kg/day.

The first three weeks carry a cortisol rise and a free-hormone dip. Whittaker and Harris (2022) found resting cortisol up 0.41 (95% CI 0.16 to 0.66) in diets shorter than 3 weeks, and Svart and colleagues (2024) found SHBG up and the free androgen index down at 3 weeks. Judging your desire in week two judges the adjustment, and the diet itself shows up later. Stress, cortisol and sex drive covers that axis.

Supervision, when calories go very low. The very low calorie ketogenic diets in Castro (2018) and Cignarelli (2023) were medically supervised protocols, a long way from a Sunday-night decision.

The hormone number is not the wanting. Da Silva Schmitt and colleagues (2023) ran the only men's trial with a sexual score attached, and it measured erections. If your labs moved and you still feel flat, why weight loss did not fix libido is the closer question, and natural testosterone support before TRT covers what a supplement can and cannot do.

What to bring to your doctor

Bring numbers and dates. A short appointment goes further when you hand over the five things below, because every study above turns on who was measured, for how long, and at what protein intake.

1. How many weeks in you are. The first three look different from month three.
2. Your protein in grams per kilo of bodyweight. That is the lever that cut testosterone once intake went above 3.4 g/kg/day.
3. Whether you are on a supervised very low calorie protocol, since that is how the diets with hormone changes were run.
4. A total testosterone, a free testosterone and an SHBG if a level is drawn. Total alone misleads here: in Cignarelli (2023) total rose 74 ng/dl while calculated free testosterone did not move.
5. The supplement question, bottle in hand, so the label gets read aloud.

The everyday levers, and where a botanical fits

Start with who this section is not for. Heart, kidney and lung conditions and blood-pressure medication are what NUUD's own label names, and they run through the populations these diet trials enrolled. The label says it plainly: avoid use if you are on blood pressure medication, have cardiovascular, renal, or pulmonary conditions, or if you are sensitive to any of the ingredients. If that sentence is about you, talk to your doctor first and bring the label.

A few ordinary things move desire in most people, and on a ketogenic diet the free ones do more work than the internet admits.

• Sleep, in quantity and quality. Castro (2018) scored sleepiness alongside sexual function in 20 people, and the two moved together. Sleep, libido and testosterone covers that.
• Movement you can sustain, keeping in mind that cortisol after long exercise ran higher on low carbohydrate in the pooled data. Exercise and libido covers the wider picture.
• Eating enough food during the adjustment weeks, because a very low calorie protocol is a stressor with a hormone signature.
• Time with a partner, with nothing expected at the end, while your body is mid-adjustment.
• A botanical supplement, if you want one, as the smallest lever on the list.

NUUD is a botanical supplement built around desire in general. It does nothing for ketosis, for testosterone, for SHBG or for weight, no study has tested this formula alongside a ketogenic diet, and it has no role in managing any medical condition. The formula is anchored by the NUUD Mushroom Complex™, with Muira Puama, Boiled Rehmannia Root, Tribulus Terrestris, and Piper Nigrum for absorption, on a timeline of roughly 30 to 60 minutes. If you take blood-pressure medication or have a heart, kidney or lung condition, the label says no, and your doctor decides the rest. If your doctor has read that label and has no objection, that is what our men's libido gummies are for. There is a women's version.

Nothing is wrong with you

Two answers online are useless. One says keto fixes your drive. The other says keto wrecks your hormones. Neither sat in the room for these studies.

In plain words, here is what was counted. Total testosterone rose by a pooled 2.86, and that rise tracked the weight people lost. High-protein low-carbohydrate versions pushed it down 1.08 in healthy men. At three weeks, SHBG went up and the free hormone index went down, in men and in women. One study of women on a supervised diet scored sexual function, and that score improved alongside 7.7 BMI units.

So the flat stretch you noticed in month one is a real adjustment with a hormone signature, and it has a habit of passing. Wanting takes longer to come back than a lab value. If what you are after is wanting to want it again, that is a slow, ordinary rebuild, and you are not broken.

Keep reading

• Why weight loss did not fix libido
• Do testosterone boosters work?
• Normal labs, low libido
• PCOS and low sex drive
• Stress, cortisol and sex drive
• Creatine and sex drive

Frequently asked questions

Does keto increase sex drive?
No trial measured desire in men on a ketogenic diet, so nobody counted. Castro and colleagues (2018) followed 20 people for 4 months on a supervised very low calorie ketogenic diet, and women's overall sexual function scores rose alongside 7.7 BMI units lost, with no comparison diet and two authors paid by the diet's manufacturer. Da Silva Schmitt and colleagues (2023) raised the erection questionnaire score in 18 hypogonadal men (p under 0.001).

Does keto raise testosterone?
Sometimes, and the rise follows the weight. Furini and colleagues (2023) pooled 7 studies and 230 people: total testosterone rose 2.86 (95% CI 0.95 to 4.77, p = 0.003), more on very low calorie versions at 6.75 (95% CI 3.31 to 10.20) than on normocaloric ones at 0.98, and meta-regression tied the rise to weight lost. Cignarelli and colleagues found total up 74 ng/dl in 22 men over 28 days with free testosterone unchanged, and Svart and colleagues found the free androgen index down at 3 weeks.

Can keto lower testosterone?
Yes, on certain versions. Whittaker and Harris (2022) pooled 27 low-carbohydrate studies in 309 healthy men: high-protein low-carbohydrate diets lowered resting total testosterone by 1.08 (95% CI -1.67 to -0.48, p under 0.01), a drop the author puts near 5.23 nmol/l. Whittaker (2023) places that cut-off above 3.4 g per kg of bodyweight per day, with no consistent decrease below it. Chen and colleagues (2023), in an umbrella review of 23 meta-analyses, also reported testosterone falling, on evidence rated weak.

Does keto affect women's hormones?
In polycystic ovary syndrome the direction is consistent: testosterone down and SHBG up. Zhang and colleagues (2019) pooled 8 randomized trials in 327 women, and diets past 4 weeks lowered total testosterone (SMD -1.79, 95% CI -3.22 to -0.36) and raised SHBG (MD 5.98, 95% CI 3.51 to 8.46). Khalid and colleagues (2023) found free testosterone down and SHBG up (d 9.086, 95% CI 3.379 to 14.792, p = 0.002). Svart and colleagues found total testosterone lower in women at 3 weeks, 0.87 against 1.1 nmol/l.

Can I take a botanical supplement on keto?
Ask your doctor first, and bring the label. It says to avoid use if you are on blood pressure medication, have cardiovascular, renal, or pulmonary conditions, or if you are sensitive to any of the ingredients. NUUD is a botanical supplement built around desire in general. It does nothing for ketosis, for testosterone, for SHBG or for weight, and no study has tested this formula alongside a ketogenic diet. Those protocols change blood work, so your doctor makes the call.

References

1. Whittaker J, Harris M. Low-carbohydrate diets and men's cortisol and testosterone: Systematic review and meta-analysis. Nutrition and health. 2022;28(4):543-554. https://pubmed.ncbi.nlm.nih.gov/35254136/
2. Paoli A, Cenci L, Pompei P, et al. Effects of Two Months of Very Low Carbohydrate Ketogenic Diet on Body Composition, Muscle Strength, Muscle Area, and Blood Parameters in Competitive Natural Body Builders. Nutrients. 2021;13(2):. https://pubmed.ncbi.nlm.nih.gov/33530512/
3. da Silva Schmitt C, da Costa CM, Souto JCS, et al. The effects of a low carbohydrate diet on erectile function and serum testosterone levels in hypogonadal men with metabolic syndrome: a randomized clinical trial. BMC endocrine disorders. 2023;23(1):30. https://pubmed.ncbi.nlm.nih.gov/36732722/
4. Castro AI, Gomez-Arbelaez D, Crujeiras AB, et al. Effect of A Very Low-Calorie Ketogenic Diet on Food and Alcohol Cravings, Physical and Sexual Activity, Sleep Disturbances, and Quality of Life in Obese Patients. Nutrients. 2018;10(10):. https://pubmed.ncbi.nlm.nih.gov/30241426/
5. Cignarelli A, Santi D, Genchi VA, et al. Very low-calorie ketogenic diet rapidly augments testosterone levels in non-diabetic obese subjects. Andrology. 2023;11(2):234-244. https://pubmed.ncbi.nlm.nih.gov/36459060/
6. Svart M, Rittig N, Luong TV, et al. Three Weeks on a Ketogenic Diet Reduces Free Testosterone and Free Estradiol in Middle-Aged Obese Men and Women. Journal of nutrition and metabolism. 2024;2024:9301369. https://pubmed.ncbi.nlm.nih.gov/39139216/
7. Wilson JM, Lowery RP, Roberts MD, et al. Effects of Ketogenic Dieting on Body Composition, Strength, Power, and Hormonal Profiles in Resistance Training Men. Journal of strength and conditioning research. 2020;34(12):3463-3474. https://pubmed.ncbi.nlm.nih.gov/28399015/
8. Furini C, Spaggiari G, Simoni M, Greco C, Santi D. Ketogenic state improves testosterone serum levels-results from a systematic review and meta-analysis. Endocrine. 2023;79(2):273-282. https://pubmed.ncbi.nlm.nih.gov/36149528/
9. La Vignera S, Condorelli RA. Dietary Interventions and Testosterone Levels in Obese Men: A Systematic Review Comparing the Mediterranean Diet, Ketogenic Diet, and Intermittent Fasting. Nutrients. 2026;18(15):. https://pubmed.ncbi.nlm.nih.gov/42588040/
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11. Whittaker J. High-protein diets and testosterone. Nutrition and health. 2023;29(2):185-191. https://pubmed.ncbi.nlm.nih.gov/36266956/
12. Chen S, Su X, Feng Y, et al. Ketogenic Diet and Multiple Health Outcomes: An Umbrella Review of Meta-Analysis. Nutrients. 2023;15(19):. https://pubmed.ncbi.nlm.nih.gov/37836444/
13. Paoli A, Mancin L, Giacona MC, Bianco A, Caprio M. Effects of a ketogenic diet in overweight women with polycystic ovary syndrome. Journal of translational medicine. 2020;18(1):104. https://pubmed.ncbi.nlm.nih.gov/32103756/
14. Corsetti V, Notari T, Montano L. Effects of the low-carb organic Mediterranean diet on testosterone levels and sperm DNA fragmentation. Current research in food science. 2023;7:100636. https://pubmed.ncbi.nlm.nih.gov/38045510/
15. Khalid K, Apparow S, Mushaddik IL, Anuar A, Rizvi SAA, Habib A. Effects of Ketogenic Diet on Reproductive Hormones in Women With Polycystic Ovary Syndrome. Journal of the Endocrine Society. 2023;7(10):bvad112. https://pubmed.ncbi.nlm.nih.gov/37693687/
16. Zhang X, Zheng Y, Guo Y, Lai Z. The Effect of Low Carbohydrate Diet on Polycystic Ovary Syndrome: A Meta-Analysis of Randomized Controlled Trials. International journal of endocrinology. 2019;2019:4386401. https://pubmed.ncbi.nlm.nih.gov/31885557/
17. Arsenaki E, Stathi D, Triantafyllidis KK, et al. The effects of ketogenic diet on polycystic ovary syndrome: A systematic review and meta-analysis. Clinical nutrition (Edinburgh, Scotland). 2026;56:106535. https://pubmed.ncbi.nlm.nih.gov/41483483/
18. Cannarella R, Rubulotta M, Leonardi A, et al. Effects of ketogenic diets on polycystic ovary syndrome: a systematic review and meta-analysis. Reproductive biology and endocrinology : RB&E. 2025;23(1):74. https://pubmed.ncbi.nlm.nih.gov/40394635/
19. Liu X, Li X, Cai D, Sun J, Bai W. Dietary patterns and testosterone balance: a review of clinical data and perspectives. Journal of advanced research. 2026;86:43-61. https://pubmed.ncbi.nlm.nih.gov/41274640/
20. Santos HO. Ketogenic diet and testosterone increase: Is the increased cholesterol intake responsible? To what extent and under what circumstances can there be benefits?. Hormones (Athens, Greece). 2017;16(3):150-160. https://pubmed.ncbi.nlm.nih.gov/29278512/

This article is for general education and is not medical or dietary advice. Obesity, metabolic syndrome, low testosterone and polycystic ovary syndrome are medical conditions that only a licensed clinician can diagnose and manage. NUUD is a botanical supplement and has no role in diagnosing, treating, curing, or preventing them or any other disease, and these statements have not been evaluated by the Food and Drug Administration. Talk with your doctor before starting any new supplement or any very low calorie diet.