No study among the sources for this article measured sexual desire in healthy people, so a low-carbohydrate diet cannot be said to raise or lower sex drive on that evidence alone, whatever changes appear in hormones or erections.
What exists is indirect: testosterone and erectile function in specific groups, where weight, age, protein share and metabolic status decide the direction. A measured hormone and a felt drive are separate things.
On the evidence retrieved here, a low-carbohydrate diet has no demonstrated effect on sex drive itself, because no source measured desire. Direction depends on weight, age, protein share and metabolic status, and on whether testosterone or erectile function changes in the group studied.
A low-carb breakfast in bed: eggs, avocado and salmon; AI-generated image.
[More research needed: among the sources retrieved for this article there is no study measuring sexual desire with a dedicated desire scale in healthy people.] The nearest proxies are total testosterone, calculated free testosterone and erectile function scores, which describe physiology rather than the experience of wanting sex.
The editorial position of Behckam.com is that a low-carb diet is neither proven to help nor proven to harm sexual desire; what the evidence shows depends on weight, age, protein share and metabolic status. A man whose testosterone rises after weight loss has a hormonal change, and whether his desire follows is not something these sources recorded.
What have trials shown about testosterone and erections?
In the 2023 open-label randomized trial of 18 hypogonadal men with metabolic syndrome, 3 months of a low-carbohydrate diet improved erectile function scores and lowered symptom scores for testosterone deficiency, with total and calculated free testosterone rising against controls in that small group.
Anthropometric measures improved only in the diet group during those 3 months. The erectile function score IIEF-5 rose in the diet group, and scores for symptoms of testosterone deficiency on ADAM and AMS fell, with p below 0.001. Total testosterone and calculated free testosterone rose in the diet group compared with controls, with p below 0.001. The authors wrote that larger studies are needed to prove effectiveness, and because the sample of 18 men was very small and the study was open label in a specific population, the results are not generalizable to healthy men or to women.
A 2023 systematic review and meta-analysis of ketogenic diets pooled 7 studies (containing 8 trials), covering 230 patients in total, and only 3 of those studies enrolled overweight or obese men. Across 111 patients, total testosterone increased after any ketogenic diet by 2.86, with a 95 percent confidence interval of 0.95 to 4.77, and the abstract does not state the unit. The increase was 6.75 (3.31 to 10.20) with very-low-calorie ketogenic diets and 0.98 (0.08 to 1.88) with normocaloric ones. In meta-regression the testosterone rise correlated with age, at an R-squared of 36.4, and with weight loss, at an R-squared of 73.6. The authors concluded that the testosterone improvement depends on both age and diet-induced weight loss, and that information on the hypothalamic-pituitary-gonadal axis was insufficient. Separately, a 2024 narrative review of the Mediterranean diet in people with metabolic syndrome reported that erectile dysfunction in men improved, and its authors stressed that more targeted studies are needed.
What difference does protein share make?
In the 2022 systematic review and meta-analysis of healthy men, which covered 27 studies and 309 participants, moderate-protein low-carbohydrate diets with under 35 percent protein had no consistent effect on resting total testosterone, while high-protein low-carbohydrate diets with 35 percent protein or more greatly decreased resting total testosterone.
In that 2022 systematic review and meta-analysis, low-carbohydrate meant 35 percent of calories or less from carbohydrate. In the short term, meaning under 3 weeks, resting cortisol rose moderately, with a standardized mean difference of 0.41 and a confidence interval of 0.16 to 0.66. In the long term, meaning 3 weeks or more, resting cortisol showed no consistent effect.
High-protein low-carbohydrate diets also reduced post-exercise total testosterone, with a standardized mean difference of -1.01 and a confidence interval of -2 to -0.01. The resting decrease carried a standardized mean difference of -1.08, a confidence interval of -1.67 to -0.48, and a magnitude of about 5.23 nmol/L. All 309 participants were healthy men, so these findings describe healthy men and not women.
What should you do if you eat low-carb and your desire has changed?
If desire has changed while you eat low-carbohydrate, review the pace of weight loss, sleep, calorie intake, protein share, stress and mood before drawing conclusions about carbohydrate. A diet should not be started on its own to treat low desire, and the trial above was supervised in a specific population.
In clinical work, specialists often see that a sudden diet change shifts sleep, calories and mood at the same time, so separating the share of carbohydrate from the share of everything else is not easy; this is a clinical impression, not a finding of these studies. If a change in desire is persistent or distressing, a medical assessment is right.
In the psychoanalytic framework of Freud, eating and sexual desire grow from a shared early bond with bodily pleasure, so changing eating patterns could also shift the experience of pleasure; this theoretical interpretation is a hypothesis and was not tested in these studies.
In the 2023 meta-analysis of ketogenic diets, total testosterone rose across 111 patients by 2.86, with a confidence interval of 0.95 to 4.77, though the unit is not stated; only 3 of its 7 studies enrolled overweight or obese men.
Does a low-carb diet improve erections?
In the 2023 trial, the erectile function score IIEF-5 rose in 18 hypogonadal men with metabolic syndrome after 3 months of a low-carbohydrate diet; the sample was small and the study was open label.
Can a high-protein low-carb diet lower testosterone?
In the 2022 meta-analysis of healthy men, diets with 35 percent protein or more greatly decreased resting total testosterone, with a standardized mean difference of -1.08 and a confidence interval of -1.67 to -0.48.
If desire drops, should you give up the diet?
No source here measured desire, so a drop cannot be attributed to carbohydrate alone; review sleep, calories, protein share, stress and the pace of weight loss, and seek medical assessment if the change persists or distresses you.
Conclusion: A Diet Is a Tool for Weight and Metabolism, Not a Drug for Desire
Across the sources retrieved here, no trial measured sexual desire itself, so a low-carbohydrate diet remains unproven for desire in either direction. Testosterone and erectile function moved in specific groups, such as 18 hypogonadal men with metabolic syndrome, and the direction tracked weight, age, protein share and metabolic status. Anyone with persistent low desire can seek assessment, while the diet stays a tool for weight and metabolism.
Looking for professional support with your relationship or mental health?
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 Endocr Disord. 2023;23(1):30. PMID: 36732722. DOI: 10.1186/s12902-023-01278-6
Furini C, Spaggiari G, Simoni M, et al. Ketogenic state improves testosterone serum levels-results from a systematic review and meta-analysis. Endocrine. 2023;79(2):273-282. PMID: 36149528. DOI: 10.1007/s12020-022-03195-5
Whittaker J, Harris M. Low-carbohydrate diets and men’s cortisol and testosterone: Systematic review and meta-analysis. Nutr Health. 2022;28(4):543-554. PMID: 35254136. DOI: 10.1177/02601060221083079
Oteri V, Galeano F, Panebianco S, et al. Influence of Mediterranean Diet on Sexual Function in People with Metabolic Syndrome: A Narrative Review. Nutrients. 2024;16(19). PMID: 39408364. DOI: 10.3390/nu16193397
Image Credits: The featured and in-text images in this article are AI-generated (Google Gemini).
