Erectile dysfunction
Tackle low testosterone

Feel like yourself again. Check your testosterone and start a personalised plan designed by expert TRT doctors.
> 500,000 patients
> 16,000 reviews
Ongoing clinical support
Regulated by CQC
4.5 Trustpilot rating
Regulated by CEDR
No hidden costs
> 500,000 patients
> 16,000 reviews
Ongoing clinical support
Regulated by CQC
4.5 Trustpilot rating
Regulated by CEDR
No hidden costs
TESTOSTERONE TESTING
Get your diagnosis
We recommend our nurse-led venous blood test, as this is the gold-standard method for accurately diagnosing testosterone deficiency and includes a doctor consultation with free confirmatory testing if your levels are low. If you’re not ready for a full diagnostic pathway, our at-home capillary test offers a convenient initial indication of your testosterone levels.
What is low testosterone?
Testosterone is the hormone that plays a role in muscle strength, energy, mood, bone density, and sexual health. Clinically low testosterone is diagnosed when blood levels fall below the healthy range on repeated testing, alongside symptoms.
When levels drop, it can affect body composition, confidence, motivation, and long-term health. Symptoms matter because they signal when your body isn’t functioning as it should, and deserve proper medical attention.
SYMPTOMS
The signs of low testosterone
If these symptoms are holding you back, Numan can help.1 If you’ve already been diagnosed with low testosterone, book a call with one of our patient support managers.
Decreased libido
Fatigue
Poor sleep
Mood changes
Difficulty concentrating
Loss of muscle mass
Increased body fat
Reduced hair growth
Causes
Causes of low testosterone
Low testosterone rarely has a single cause. For many men, it’s the result of overlapping factors:2
Age-related decline
Testosterone levels gradually decline with age.
Brain-to-testes hormone signalling becomes less efficient over time.
Testes may start to 'fail' as men grow older.
Changes in sleep, activity and body composition can accelerate the drop.
Medical conditions
Excess body fat can disrupt the hormone signals needed for testosterone production.
Type 2 diabetes is closely linked to lower testosterone and impaired hormone balance.
Pituitary or hypothalamus disorders can reduce the signals that stimulate testosterone production.
Some medications may reduce T levels.
Lifestyle factors
Chronic stress can lower testosterone by disrupting hormone balance.
Testosterone is produced during deep sleep, so poor sleep directly reduces levels.
Excess alcohol, smoking, and recreational drug use can impair testosterone production.
Poor diet can limit the nutrients needed for hormone production.
Low physical activity reduces the body’s natural testosterone stimulation.
SHINING THE SPOTLIGHT
Symptoms of low testosterone creep in gradually, but because they build slowly, they’re often swept under the carpet, leaving many men undiagnosed and unsupported.
At Numan, we don’t overlook it. We investigate properly, with thorough testing, doctor-led consultations, and a clear pathway to a full range of effective treatment options.
25%
of men under 40 may experience signs of low testosterone, rising to roughly 40% in those over 45.3
33%
of erectile dysfunction cases may be linked to low testosterone.4
90%
of men with low testosterone go undiagnosed or misdiagnosed with conditions like depression.5
Digital clinic
Benefits of the Numan TRT Programme
Here’s what to expect from our three-part online TRT programme.
Clinician-led treatment
Tailored treatment plans, designed by our clinicians to support your health journey.
Ongoing clinical care
Clinicians will help you manage potential side effects, make dosage adjustments, provide follow-up blood tests, and answer any questions you might have throughout the programme.
Doorstep delivery
Regardless of your treatment, your package will be delivered in a discreet box, right to your doorstep.
Results
What results to expect when you start TRT
Clinical studies have observed that as testosterone levels increase, some men report gradual improvements in areas such as energy, mood and sexual wellbeing over time. Changes don’t happen overnight, and everyone responds differently, but treatment is designed to support steady, clinically-monitored progress.6
Month 1-3
Higher libido
Stronger erections
Improved mood and energy
Month 3-6
Higher strength and endurance
Fat loss
Motivation and mental clarity
Month 6 onwards
Faster recovery
Ongoing reduction in visceral fat
Bone strength
UK DOCTORS AND CLINICIANS
Your expert team
Mo Dekmak
Head of Clinical Product
MPharm PgDip IPresc

Dr Dimitris Schizas
Numan Doctor
MBBS MRCGP MSC BSSM

Dr Michael Lacey
Numan Doctor
MBChB BSc (Hons) MRCGP

Dr Alexandra Davidson
Numan Doctor
BSc (Hons) MBBS MRCGP AFHEA MA (Hons) AFMCP

Abby Watts
Senior Nurse Prescriber
BSc Adult Nursing, IP

FAQS
Your questions answered
Knowledge
Testosterone: what you need to know
References
*Low testosterone levels must be confirmed on the initial VBT to get a free doctor consultation. Normal results do not warrant further clinical intervention.
Morales A, Bebb RA, Manjoo P, Assimakopoulos P, Axler J, Collier C, et al. Diagnosis and management of testosterone deficiency syndrome in men: clinical practice guideline. CMAJ [Internet]. 2015;187(18):1369–77.
Sizar O, Leslie SW, Schwartz J. Male hypogonadism. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2025.
Andre B. Araujo, Gretchen R. Esche, et al. Prevalence of Symptomatic Androgen Deficiency in Men, The Journal of Clinical Endocrinology & Metabolism, Volume 92, Issue 11, 1 November 2007, Pages 4241–4247
Rabijewski M, Papierska L, Kozakowski J, Zgliczyński W. The high prevalence of testosterone deficiency in population of Polish men over 65 years with erectile dysfunctions. Aging Male. 2012;15(4):258–62.
Layton JB, Li D, Meier CR, Sharpless JL, Stürmer T, Jick SS, et al. Testosterone lab testing and initiation in the United Kingdom and the United States, 2000 to 2011. J Clin Endocrinol Metab . 2014;99(3):835–42
Morley J. The benefits and risks of testosterone replacement therapy: a review. Ther Clin Risk Manag. 2009;427.
Kumagai H, Zempo-Miyaki A, Yoshikawa T, Tsujimoto T, Tanaka K, Maeda S. Lifestyle modification increases serum testosterone level and decrease central blood pressure in overweight and obese men. Endocr J. 2015;62(5):423–30.
Reclaim Your Vitality
Experiencing decreased libido, fatigue, or increased body fat? You might have low testosterone. Check if low-T is affecting you today.
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