Testosterone and Visceral Belly Fat: UK Evidence

Does increasing your testosterone help you lose visceral belly fat? It is a question raised increasingly in clinical consultations and online health discussions. Visceral fat, the deep abdominal fat surrounding internal organs, is strongly linked to metabolic disease and is influenced by hormonal factors including testosterone. In men with confirmed hypogonadism, testosterone replacement therapy (TRT) can produce meaningful reductions in visceral fat. However, the evidence in men with normal testosterone levels is far weaker, and the picture in women is more complex still. This article explains what the clinical evidence and UK guidance actually say.

What is visceral belly fat and why does it matter for your health?

Visceral fat is deep abdominal fat surrounding internal organs, strongly associated with insulin resistance, type 2 diabetes and cardiovascular disease. NHS guidance uses waist circumference above 94 cm in men or 80 cm in women as a practical indicator of increased health risk.

Visceral fat is the metabolically active fat stored deep within the abdominal cavity, surrounding organs such as the liver, pancreas and intestines, and it carries significantly greater health risks than subcutaneous fat sitting just beneath the skin. Unlike the fat you can pinch at the waistline, visceral fat is not visible from the outside, yet it is strongly associated with insulin resistance, type 2 diabetes, cardiovascular disease, metabolic dysfunction-associated steatotic liver disease (previously termed non-alcoholic fatty liver disease) and certain cancers.

The NHS uses waist circumference as a practical proxy for visceral fat burden. According to NHS guidance, a waist measurement above 94 cm in men or above 80 cm in women indicates increased health risk, with measurements above 102 cm in men and 88 cm in women indicating substantially higher risk. The NHS also notes that people of South Asian, Black African, African Caribbean and Chinese descent may face an increased risk at lower waist measurements, and that the above thresholds may not apply equally to all ethnic groups.^[3] If you are unsure whether these thresholds apply to you, your GP can advise on your individual risk.

Visceral fat is hormonally active, releasing inflammatory cytokines and free fatty acids into the portal circulation. This creates a self-reinforcing cycle: excess visceral fat disrupts hormonal signalling, including the hypothalamic-pituitary-gonadal axis, which in turn can suppress testosterone production in men. Understanding this bidirectional relationship is central to evaluating whether testosterone therapy can meaningfully reverse visceral fat accumulation.

How does testosterone affect where your body stores fat?

Testosterone inhibits visceral fat accumulation by promoting lipolysis, preserving lean muscle mass and acting on androgen receptors in adipose tissue. When testosterone falls, these protective effects diminish and visceral fat tends to increase.

Testosterone influences fat distribution by promoting fat oxidation, preserving lean muscle mass and directing adipose tissue away from central depots. Lower testosterone levels are associated with preferential accumulation of visceral fat. This relationship is well established in male physiology and is increasingly recognised in women, where androgens also play a regulatory role in body composition.

In men, testosterone acts on androgen receptors in adipose tissue to inhibit the differentiation of pre-adipocytes into mature fat cells, particularly in the visceral compartment.^[4][5] It also supports lipolysis (the breakdown of stored triglycerides) and the maintenance of skeletal muscle, which is metabolically active tissue that contributes to resting energy expenditure. When testosterone falls, as occurs naturally with ageing or in hypogonadism, these protective effects diminish and visceral fat tends to accumulate. Sex hormone-binding globulin (SHBG) levels also rise with age and obesity, reducing the proportion of biologically available testosterone and compounding this effect.^[6] Aromatisation of testosterone to oestradiol in adipose tissue adds further complexity to the hormonal picture in men with excess visceral fat.

In women, androgens including testosterone are produced by the ovaries and adrenal glands and contribute to lean mass maintenance. The hormonal shifts of the menopause transition, which include declining oestrogen alongside relative changes in androgen balance, are associated with a redistribution of fat towards the abdomen. However, the mechanisms in women are more complex and less well characterised than in men.

It is important to note that testosterone does not act in isolation. Insulin, cortisol, growth hormone and oestrogen all interact with fat distribution, and no single hormone fully explains the pattern of visceral adiposity in any individual. There is also considerable inter-individual variability in how body composition responds to changes in androgen levels.

Does raising testosterone levels actually reduce visceral fat?

TRT reduces visceral fat meaningfully in men with confirmed hypogonadism, but evidence in men with normal testosterone levels is considerably weaker. Supraphysiological doses carry serious health risks and are not a legitimate clinical strategy.

Clinical evidence suggests that testosterone replacement therapy (TRT) in men with confirmed hypogonadism produces meaningful reductions in visceral fat, though the magnitude varies and results in men with normal testosterone levels are considerably less convincing.

Several randomised controlled trials and longer-term observational studies have demonstrated reductions in waist circumference, total body fat percentage and visceral fat area in hypogonadal men receiving TRT, alongside improvements in insulin sensitivity. Long-term observational registry data from studies of testosterone undecanoate injections in hypogonadal men (including work by Saad, Yassin and colleagues) have reported sustained reductions in waist circumference and body weight over several years, alongside improvements in metabolic markers. These findings should be interpreted with caution, however, as observational designs cannot exclude confounding.

The TRAVERSE trial, a large randomised cardiovascular safety trial of testosterone replacement in men with hypogonadism and elevated cardiovascular risk (published in the New England Journal of Medicine in 2023), provided important safety data and reported modest improvements in body composition.^[11] Body composition in this trial was assessed using measures including waist circumference and body weight rather than direct visceral fat imaging such as CT or MRI, which is an important limitation when interpreting the visceral fat-specific findings. Crucially, the trial population had confirmed low testosterone, reinforcing that any benefit appears specific to those with a genuine deficiency.

In men with normal testosterone levels, the evidence for using testosterone to reduce visceral fat is considerably weaker. Supraphysiological doses, such as those used in anabolic steroid misuse, can alter body composition but carry serious health risks and are not a legitimate clinical strategy. For women, the evidence base for testosterone therapy specifically targeting visceral fat remains limited, and no UK-licensed testosterone product is currently indicated for this purpose in women.

The key clinical principle is that TRT should not be initiated with the goal of reducing visceral fat in men who have normal testosterone levels. Any benefit relates to restoring physiological testosterone concentrations in those with confirmed hypogonadism.

What does the NHS and current UK evidence say about testosterone therapy?

The NHS provides TRT only for clinically confirmed hypogonadism, diagnosed via at least two low early-morning testosterone measurements plus symptoms. TRT is not commissioned as a weight-loss treatment, and visceral fat reduction is not a licensed indication.

The NHS provides testosterone replacement therapy for men with clinically confirmed hypogonadism, a condition characterised by consistently low serum testosterone levels combined with symptoms such as fatigue, reduced libido, erectile dysfunction and loss of muscle mass. Both NICE guidance and British Society for Sexual Medicine (BSSM) guidelines recommend that diagnosis should be based on at least two early-morning testosterone measurements below the laboratory reference range, alongside a thorough clinical assessment.^[13] Early-morning sampling is recommended because testosterone levels are highest in the morning; fasting is generally advised where possible, though this is not uniformly mandated across all UK guidance. Additional investigations including LH, FSH, SHBG and prolactin may be requested where clinically indicated.

TRT is not commissioned by the NHS as a weight-loss treatment, and no UK-licensed testosterone product carries an indication for visceral fat reduction as a standalone goal. Integrated Care Boards (ICBs) make local commissioning decisions, and access to TRT on the NHS varies by region, with specialist referral typically required. Men who do not meet the diagnostic criteria for hypogonadism are unlikely to be offered TRT through NHS pathways, regardless of their body composition concerns.

For women, the NICE menopause guideline (NG23, updated 2024) acknowledges that testosterone supplementation may be considered for hypoactive sexual desire disorder (HSDD) in postmenopausal women when standard hormone replacement therapy has not been effective.^[12] No licensed female testosterone product exists in the UK, and prescribing is off-label, typically using male-licensed preparations at lower doses under specialist supervision, with shared decision-making and informed consent.^[12][13] Visceral fat reduction is not a recognised indication.

Private prescribing of testosterone is available through regulated UK services. Bolt Pharmacy is a GPhC-registered UK online pharmacy offering online consultations with prescriber review, where testosterone therapy may be one option a prescriber considers if it is clinically appropriate following assessment. Any private prescribing should still follow BSSM and NICE-aligned diagnostic standards.

If you are concerned about symptoms that may suggest low testosterone, speak to your GP in the first instance. They can arrange appropriate blood tests and refer you to a specialist if needed.

Are there risks or side effects of using testosterone to lose belly fat?

TRT risks include erythrocytosis, impaired fertility, acne, fluid retention, gynaecomastia and worsening sleep apnoea, requiring regular monitoring. Testosterone is contraindicated in known or suspected prostate or breast cancer and should never be used unsupervised solely to reduce belly fat.

Testosterone therapy carries a range of potential adverse effects that must be weighed carefully against any anticipated benefit, and it should never be used outside a supervised clinical framework with the aim of reducing belly fat alone. The risks differ between men and women and depend on dose, formulation and duration of use.

Key contraindications to testosterone therapy (based on UK product information for licensed testosterone preparations such as Nebido and Testogel) include known or suspected prostate cancer, breast cancer, and markedly elevated haematocrit or polycythaemia. Testosterone should not be used in men where a rise in haematocrit would pose a significant risk.

In men, recognised adverse effects of TRT include:

• Erythrocytosis (raised red blood cell count), which increases the risk of thrombosis and requires regular haematocrit monitoring

• Suppression of spermatogenesis, which can impair fertility; recovery after stopping treatment is variable and cannot be guaranteed, so men who wish to preserve fertility should discuss this with their prescriber before starting TRT

• Acne and oily skin

• Fluid retention

• Gynaecomastia (breast tissue enlargement), particularly if testosterone is converted to oestradiol

• Worsening of obstructive sleep apnoea

• Prostate-related effects, including a potential increase in prostate-specific antigen (PSA), requiring monitoring in older men

Baseline and ongoing monitoring is an important part of safe TRT. This typically includes haematocrit and haemoglobin at baseline, at three to six months, and then annually; PSA and clinical prostate assessment in men aged 40 and over or those at higher risk; assessment for obstructive sleep apnoea; and review of lipids and liver function where clinically indicated. Your prescriber will advise on the monitoring schedule appropriate for you.

In women, off-label testosterone use at physiological doses is generally considered to have a more limited adverse effect profile, but higher doses can cause virilisation, including acne, hirsutism and voice changes. Women of childbearing potential should use effective contraception during testosterone treatment, as testosterone is harmful to a developing foetus. Testosterone must not be used during pregnancy or whilst breastfeeding.

Suspected adverse drug reactions to testosterone should be reported to the MHRA via the Yellow Card scheme at yellowcard.mhra.gov.uk. Reports can be submitted by both patients and healthcare professionals.

Using testosterone without medical supervision, including through anabolic steroids obtained outside regulated channels, carries substantially greater risks. Illicit use of 17-alpha-alkylated oral anabolic steroids in particular is associated with hepatotoxicity, in addition to cardiovascular harm and psychiatric effects. Anyone experiencing chest pain, severe breathlessness or signs of a blood clot while taking testosterone should call 999 immediately. For other concerning symptoms, contact your GP or call NHS 111 for urgent advice.

What else can help reduce visceral fat alongside hormonal treatment?

Aerobic and resistance exercise, a diet low in ultra-processed foods and refined carbohydrates, and improved sleep are the most evidence-based approaches to reducing visceral fat. GLP-1 receptor agonists such as semaglutide may also be considered for eligible patients under NICE-recommended pathways.

Lifestyle modification remains the most evidence-based and widely recommended approach to reducing visceral fat, and it is effective both independently and as a complement to hormonal treatment where that is clinically indicated. NICE public health guidance consistently identifies sustained caloric deficit, increased physical activity and improved sleep as the cornerstones of visceral fat reduction.

Diet plays a central role. Reducing ultra-processed foods, refined carbohydrates and added sugars while increasing dietary fibre, lean protein and unsaturated fats supports both weight loss and improvements in insulin sensitivity. The NHS Eatwell Guide provides a practical framework for balanced eating that is appropriate for most adults.

Physical activity is particularly effective at targeting visceral fat. Both aerobic exercise (such as brisk walking, cycling or swimming) and resistance training contribute to visceral fat reduction. There is evidence suggesting that resistance training has a meaningful effect on visceral adiposity, partly through its effects on muscle mass and resting metabolism, alongside the reductions in total body fat achieved through aerobic activity. The UK Chief Medical Officers' Physical Activity Guidelines recommend at least 150 minutes of moderate-intensity aerobic activity per week for adults, alongside muscle-strengthening activities on two or more days.^[15][16]

Sleep quality and stress management are often underappreciated. Chronic sleep deprivation and elevated cortisol from psychological stress both promote visceral fat accumulation through distinct hormonal pathways. Addressing these factors can meaningfully support body composition improvements.

For people with obesity and related metabolic conditions, NICE-recommended pharmacological options such as GLP-1 receptor agonists (for example, semaglutide as Wegovy, available in doses up to 2.4 mg weekly for the standard maintenance dose and up to 7.2 mg weekly at the higher licensed strength) have demonstrated significant reductions in visceral fat in clinical trials, including body composition substudies of the STEP programme.^[19] These medicines may be considered alongside lifestyle intervention where eligibility criteria are met, subject to local ICB commissioning and specialist weight management pathways. They are distinct from testosterone therapy and work through entirely different mechanisms. As with all pharmacotherapy for weight management, they are prescribed only where clinically appropriate and as an adjunct to lifestyle change.

Scientific References

1. Calculate your waist to height ratio – NHS.
2. Waist circumference as a measure for indicating need for weight management. Lean ME et al. BMJ. 1995..
3. Appendix A1: Summary of evidence from surveillance (NG246) – NICE.
4. Testosterone metabolites differentially regulate obesogenesis and fat distribution. Molecular Metabolism. 2021..
5. Body composition changes and inhibition of fat development in vivo implicates androgen in regulation of stem cell lineage allocation. Journal of Cellular Biochemistry. 2011..
6. Association of testosterone and sex hormone-binding globulin with fat distribution in men: a quantitative water-fat MRI study. Quantitative Imaging in Medicine and Surgery. 2025..
7. Effects of long-term treatment with testosterone on weight and waist circumference in hypogonadal men. Saad F, Yassin A et al. 2016..
8. Long-term testosterone therapy improves liver parameters and steatosis in hypogonadal men. The Aging Male. 2021..
9. Men with testosterone deficiency and a history of cardiovascular diseases benefit from long-term testosterone therapy. Vascular Health and Risk Management. 2016..
10. Effects of continuous long-term testosterone therapy on anthropometric, endocrine and metabolic parameters for up to 10 years in 115 hypogonadal elderly men. Andrologia. 2016..
11. Cardiovascular Safety of Testosterone-Replacement Therapy (TRAVERSE trial). Lincoff AM et al. NEJM. 2023..
12. Menopause: identification and management (NG23) – NICE.
13. Testosterone – BNF/NICE.
14. Nebido 1000 mg/4 ml solution for injection – EMC SmPC.
15. Physical Activity Guidelines: UK Chief Medical Officers' Report – GOV.UK.
16. Physical activity guidelines for adults aged 19 to 64 – NHS.
17. Medicines regulator approves up to 7.2 mg dose of semaglutide (Wegovy) for patients with obesity only – GOV.UK.
18. Wegovy (semaglutide) EPAR product information – EMA.
19. Effect of continued weekly subcutaneous semaglutide vs placebo on weight loss maintenance in adults with overweight or obesity. Rubino D et al. JAMA. 2021..
20. Aerobic exercise and weight loss in adults: a systematic review. Jayedi A et al. JAMA Network Open. 2024..
21. A systematic review and meta-analysis of the effect of exercise on visceral adipose tissue. Ismail I et al. 2012..
22. Effects of concurrent training on fat mass and its distribution in individuals with overweight or obesity. BMC Public Health. 2025..
23. Comparative efficacy of exercise type on visceral adipose tissue in patients with prediabetes and type 2 diabetes mellitus. Obesity Reviews. 2024..
24. Effect of exercise intervention dosage on reducing visceral adipose tissue. International Journal of Obesity. 2021..

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