Beetroot Juice Helps FMD, Not Strength, in AAS Users

Beetroot juice improved a vascular biomarker in bodybuilders with a history of anabolic-androgenic steroid (AAS) abuse, yet it did not lower blood pressure, change autonomic cardiovascular measures, or increase strength. That split is the useful finding. A supplement can improve the lining of blood vessels without repairing the wider cardiovascular problems that AAS use may create.

In a small double-blind crossover trial, nitrate-rich beetroot juice raised flow-mediated dilation (FMD) by 2.37 percentage points before exercise and 2.57 percentage points after exercise versus nitrate-depleted placebo. Both differences reached statistical significance. But the same intervention produced essentially no strength difference: 0.02 kgf between conditions, with p=0.99. The trial does not show that beetroot juice reverses AAS-related cardiovascular damage. It shows that an endothelial response remains available to dietary nitrate after AAS exposure.

A measurable FMD gain, with no broader acute payoff

The direct evidence comes from da Silva et al.'s 2026 crossover trial in 13 adult men with self-reported histories of AAS abuse. Their mean age was 31 years, mean body-mass index was 30 kg/m², and baseline systolic blood pressure averaged 132 mmHg. Each participant received a single dose of nitrate-rich beetroot juice and a nitrate-depleted placebo in separate conditions; investigators measured vascular and performance outcomes at rest and after acute exercise.

The biochemical result shows that the intervention did what beetroot juice is supposed to do. Salivary nitrate increased by 40.6 μM (p<0.001), and salivary nitrite increased by 3.1 μM (p=0.002). Those compounds feed the nitrate-to-nitrite-to-nitric-oxide pathway. FMD, a test of how well an artery dilates after increased blood flow, rose by 2.37% before exercise (p=0.02) and 2.57% afterward (p=0.01).

FMD matters as a marker of endothelial function, but it is still a surrogate endpoint. The trial did not report fewer cardiovascular events, improved heart structure, or reversal of vascular disease. It also did not find an acute reduction in systolic or diastolic blood pressure, or a change in autonomic cardiovascular tone. The published summary available here does not provide confidence intervals for these estimates, so the precision of the FMD and null findings cannot be judged beyond the reported p values.

Why the biomarker can improve while blood pressure does not

Nitrate from beetroot can increase nitric oxide through a route that does not depend on endothelial nitric oxide synthase, or eNOS. That distinction may matter in oxidative-stress states. DuBose et al.'s 2022 human mechanistic study identified tetrahydrobiopterin (BH4) deficiency as a mediator of oxidative-stress-related endothelial dysfunction in menopausal women. When BH4 is inadequate, eNOS can become "uncoupled," producing superoxide rather than nitric oxide.

The AAS trial did not measure BH4, eNOS coupling, arterial stiffness, or the causes of any blood-pressure resistance. So it cannot prove this mechanism in AAS users. Still, the biology offers a coherent explanation for the observed pattern: exogenous nitrate may improve nitric-oxide availability enough to improve FMD even if it does not correct the upstream oxidative environment.

Blood pressure depends on more than endothelial signaling at one moment. Vascular smooth-muscle behavior, blood volume, sympathetic activity, arterial wall properties, and other physiology all contribute. An acute FMD improvement therefore does not require an acute blood-pressure reduction. The plumbing analogy is imperfect, but useful: a vessel can dilate better during a test while the rest of the cardiovascular system remains under strain.

Other studies support the endothelial effect, not a cure claim

The result fits a broader pattern in other populations. In resistance-trained people, Morishima et al. in 2025 found that beetroot juice taken before high-intensity resistance exercise prevented the usual temporary decline in endothelial function. A 2022 crossover study by the same group found that prior beetroot juice offset endothelial dysfunction after prolonged sitting. These trials support an acute endothelial effect during different short-term vascular stresses, but neither study establishes benefit in men using AAS.

Evidence also suggests that duration may matter. A 2024 randomized, placebo-controlled, double-blind crossover trial reported clinically significant improvement in basal macrovascular function after seven days of dietary nitrate in postmenopausal women. In a separate 12-week randomized trial, nitrate-rich beetroot extract improved lower-limb vascular function and serum angiogenic potential in postmenopausal women.

Those are relevant clues, not proof that weeks of beetroot juice will lower blood pressure in AAS users. Postmenopausal women and men with AAS exposure differ in hormones, drug exposure, vascular physiology, and likely sources of endothelial dysfunction. A triple-blind randomized trial in hypertensive postmenopausal women also found improved cardiovascular responses after aerobic exercise with acute and short-term nitrate-rich beetroot juice. That result makes the AAS trial's null hemodynamic finding look population- and design-specific rather than a general property of nitrate.

Performance claims do not survive this trial

Beetroot juice has a reputation as a performance aid, largely because nitrate can affect oxygen use and blood flow in some exercise settings. This trial tested a different question in a specific population: acute isometric strength in men with histories of AAS abuse. It found no effect. The 0.02 kgf between-condition difference, with p=0.99, is about as close to a null result as a study can report.

That does not settle whether beetroot juice affects endurance performance, training volume, or recovery in other people. It does mean that this trial provides no basis to market a single serving of beetroot juice as a strength enhancer for AAS-using bodybuilders. Improved FMD did not translate into the measured strength outcome.

What the study can and cannot tell us

• It can tell us: A single nitrate-rich beetroot-juice dose increased salivary nitrate and nitrite and improved FMD relative to placebo in this 13-person crossover trial.
• It cannot tell us: Whether chronic use lowers blood pressure, reduces cardiovascular events, reverses AAS-related cardiac or vascular damage, or improves long-term performance.
• Its small sample matters: Thirteen participants leave limited ability to detect modest blood-pressure effects. A non-significant result is not evidence that a small effect is impossible.
• Exposure details matter: Self-reported AAS history leaves uncertainty about compounds, cumulative dose, duration, and current use.
• The clinical size of the FMD change remains unclear: The available evidence does not establish baseline FMD deficits in AAS users compared with matched AAS-naive men, so it cannot show what fraction of any deficit the 2.37% to 2.57% increase restored.

Studies in peripheral artery disease offer another reason not to force one interpretation onto every group. Pekas et al. in 2021 found that body-mass-normalized dietary nitrate improved both endothelial function and walking capacity in patients with peripheral artery disease. In the AAS trial, FMD improved but strength did not. Different participants, doses, functional endpoints, and disease processes can produce different downstream results.

Beetroot juice has evidence for an acute endothelial effect in this small AAS-exposed group. It does not have evidence here for blood-pressure control, cardiovascular recovery, or extra strength.

For someone with past or current AAS exposure, beetroot juice is best viewed as a possible adjunct for endothelial function, not a substitute for medical evaluation of hypertension, dyslipidemia, elevated hematocrit, cardiac changes, or other AAS-related risks. The study that would change the practical answer would follow AAS users for at least several weeks and measure FMD, blood pressure, and arterial stiffness together. Until then, the honest conclusion is narrow: the nitrate pathway moved, FMD improved, and the rest of the measured system stayed put.