What does L-citrulline do for women? What the research does and doesn't show

The evidence doesn't support a women-specific benefit of L-citrulline separate from what's been found in mixed-sex or general trials — most of citrulline's exercise-performance research was done in men only. What direct female-specific research exists is smaller and more recent: two trials in postmenopausal or older women found improvements in blood-vessel function and physical function, and one mixed-sex trial found no benefit for either sex on a strength measure.

What the evidence doesn't support

It doesn't support L-citrulline as a treatment for any women's health condition — none of the trials below tested a diagnosed condition, and none involved women below their 50s except as a minority in one mixed-sex trial. It doesn't support a female-specific performance edge in young or exercise-trained women — the largest exercise-performance evidence base (bench press, muscular endurance) was built almost entirely on men, and the one trial that included a substantial number of women found no strength benefit for either sex. It doesn't support routine use for a general "women's health" purpose; every positive female-specific finding below is narrow — a specific age group, a specific measurement, over a matter of weeks.

What the trials found

A 2026 pilot randomized controlled trial gave 20 community-dwelling women aged 60-75 a 6-week exercise program plus 3 g/day of citrulline malate or placebo. The citrulline group improved significantly more on a sit-to-stand physical-function test than placebo (p=0.023), with non-significant trends toward greater improvement in 6-minute walk distance and a physical-performance battery score. No significant differences turned up in cortisol, testosterone, creatine kinase, glucose or quality-of-life measures, and no adverse events were reported. The authors call this pilot's results preliminary, given its small size, and say larger trials are needed.

A 2024 randomized, placebo-controlled trial gave 22 hypertensive postmenopausal women 10 g/day of L-citrulline or placebo for 4 weeks. Citrulline significantly improved a measure of blood-vessel function (flow-mediated dilation), lowered resting aortic systolic blood pressure, and improved blood flow and muscle oxygenation during handgrip exercise, compared with placebo. It's a specific population — postmenopausal women with diagnosed hypertension — not a general finding for women without that condition.

A 2012 randomized, crossover trial gave 14 adults with prehypertension or stage-1 hypertension — 11 women, 3 men — 6 g/day of L-citrulline/L-arginine from watermelon extract, or placebo, for 6 weeks each. Blood pressure and a measure of arterial stiffness were both significantly lower after the citrulline period. The trial wasn't designed or powered to compare men and women against each other; it reports the group as a whole.

Against those three positive findings, a 2024 randomized, double-blind crossover trial gave 43 young, trained adults — 21 women, 22 men, mean age 24.2 — a single 5.3 g dose of plain L-citrulline or the same amount as citrulline malate before strength testing. Neither form improved maximal strength, jump performance, or strength-endurance in the squat or bench press for the group overall, compared with placebo. The trial didn't publish separate results by sex, so it doesn't show whether women specifically responded differently from men — it shows no effect for the group as tested.

A 2026 narrative review summarizes early research combining L-citrulline with exercise in postmenopausal women, covering arterial stiffness, leg strength, lean mass and physical function. It describes the pattern above as promising but explicitly states that larger, higher-quality randomized trials are still needed to confirm the benefit and establish dosing — a caution worth taking as seriously as the individual trial findings.

What's missing

We found no trial testing L-citrulline in young or premenopausal women specifically, no trial on menstrual-cycle-related outcomes, and no trial testing citrulline for a symptom specific to pregnancy or menopause. Nearly all of citrulline's larger exercise-performance trials — the ones behind most "L-citrulline benefits" claims — were conducted in men only, which means claims about exercise performance don't have dedicated female evidence behind them one way or the other.

Questions people ask

Can women take L-citrulline?

The trials that exist — mostly in postmenopausal or older women — didn't report safety problems. The larger exercise-performance evidence base was built mostly in men, which is a gap in the research, not a reason women were excluded for a safety reason.

What does L-citrulline do for women specifically?

In the trials available: blood-vessel function improved and blood pressure was lowered in postmenopausal women with hypertension who took it (one small trial), and physical function improved in a small pilot trial of older women who combined citrulline with exercise. Neither finding has been replicated in a larger trial, and citrulline's much larger exercise-performance evidence base doesn't report results specific to women.

Is L-citrulline good for women's exercise performance?

The one trial that included a substantial number of women (21 of 43 participants) found no strength or jump-performance benefit for the group overall, and didn't report results by sex separately. Most of the positive exercise-performance trials elsewhere were conducted in men only.

When to talk to a doctor

L-citrulline is not a treatment for any diagnosed condition, in women or otherwise, and nothing above should stand in for a doctor's evaluation. If you have diagnosed hypertension, are pregnant or breastfeeding, or take a regular prescription medication, talk to a doctor before starting L-citrulline.

Related reading: L-citrulline benefits: what the research does and doesn't show and does L-citrulline help with blood pressure?.