Every PepLab protocol is grounded in peer-reviewed clinical research. Below you'll find the science behind each service, the clinical impact data, and the references behind every claim.
Bioidentical hormone replacement therapy restores estrogen, progesterone, and testosterone to optimal physiological levels using hormones chemically identical to those your body produces. Unlike synthetic hormones, bioidentical compounds have the same molecular structure as endogenous hormones, allowing them to bind to receptors with the same signaling fidelity.
Compounded bioidentical HRT allows precise dose customization based on your labs and symptom response — something standardized pharmaceutical doses cannot achieve.
Hot flashes, night sweats, vaginal dryness, and sleep disruption — all driven by estrogen decline — respond reliably to appropriately dosed HRT. Multiple RCTs demonstrate 60–80% reduction in vasomotor symptoms.
Estrogen is the primary regulator of bone resorption. Women lose up to 20% of bone density in the first 5–7 years after menopause. HRT consistently arrests bone loss and reduces fracture risk by 25–30%.
The "timing hypothesis" — now well-supported in literature — shows that HRT initiated during the critical window (within 10 years of menopause or before age 60) is cardioprotective. The KRONOS Early Estrogen Prevention Study (KEEPS) confirmed no increase in cardiovascular risk in early initiation.
Estrogen protects neuronal function, reduces amyloid deposition, and improves cerebral blood flow. Studies show 30–50% reduction in depressive symptoms and improvements in verbal memory and executive function with optimized hormone levels.
Testosterone therapy in women with documented deficiency significantly improves sexual function, energy, mood, and body composition. The APHRODITE trial and subsequent meta-analyses confirm efficacy and safety.
The TRAVERSE trial (2023, NEJM) — the largest TRT safety trial to date — found no increase in cardiovascular events with testosterone replacement in symptomatic hypogonadal men. Improvements in energy, libido, body composition, and mood are well-documented.
Manson JE, et al. Menopausal hormone therapy and long-term all-cause and cause-specific mortality. JAMA. 2017;318(10):927–938.
Langer RD, et al. The KRONOS Early Estrogen Prevention Study (KEEPS). Climacteric. 2014;17(Suppl 2):3–17.
Bhasin S, et al. Testosterone therapy in men with hypogonadism — TRAVERSE trial. N Engl J Med. 2023;389:107–117.
Davis SR, et al. Testosterone for low libido in postmenopausal women not taking estrogen. N Engl J Med. 2008;359:2005–2017.
The Menopause Society. 2022 Hormone Therapy Position Statement. Menopause. 2022;29(7):767–794.
Peptides are short-chain amino acid sequences that function as biological messengers — instructing cells to produce hormones, repair tissue, reduce inflammation, or regulate metabolic function. Unlike exogenous hormones, peptides work by signaling your body's own systems, which means they tend to produce more physiological responses with lower risk of suppression.
Peptide therapy has been used in clinical settings for decades — insulin, growth hormone, and oxytocin are all peptides. The emerging class of research and off-label peptides extends this principle to tissue repair, immune regulation, and longevity.
Body Protection Compound-157 is a synthetic pentadecapeptide derived from gastric juice. Extensive research demonstrates accelerated healing of tendon, ligament, bone, and muscle tissue, as well as gastroprotective and anti-inflammatory effects. Widely used by athletes and post-surgical patients.
Sermorelin stimulates the pituitary gland to produce and release growth hormone naturally — avoiding the suppression and side effects of exogenous HGH. Improves body composition, recovery, sleep quality, and energy in adults with age-related GH decline.
This combination amplifies the natural pulsatile release of growth hormone during deep sleep. Clinical data shows improved sleep architecture, enhanced muscle recovery, and favorable changes in body composition when dosed pre-sleep.
A modified fragment of HGH (aa 176–191) that stimulates fat breakdown without affecting growth or insulin sensitivity. Clinical trials demonstrated significant reduction in visceral adipose tissue — the most metabolically dangerous fat depot.
Sikiric P, et al. Stable gastric pentadecapeptide BPC 157: novel therapy in gastrointestinal tract. Curr Pharm Des. 2018;24(18):1990–2001.
Prakash A & Goa KL. Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency. BioDrugs. 1999;12(2):139–157.
Walker RF. Sermorelin: a better approach to management of adult-onset growth hormone insufficiency? Clin Interv Aging. 2006;1(4):307–308.
Ng FM, et al. Metabolic studies of a growth hormone-releasing peptide fragment AOD9604 in humans. J Endocrinol. 2000;166(3):525–533.
GLP-1 receptor agonists represent one of the most significant advances in metabolic medicine in decades. Originally developed for type 2 diabetes, semaglutide and tirzepatide have demonstrated remarkable efficacy in weight management, cardiovascular protection, and potentially neuroprotection — in both diabetic and non-diabetic populations.
PepLab GLP-1 protocols are physician-supervised, hormone-integrated, and designed to preserve lean mass — the single most important factor for long-term metabolic health that most GLP-1 prescribers ignore.
The STEP and SURMOUNT trial series established semaglutide and tirzepatide as the most effective pharmacological weight loss interventions available. Results consistently exceed those of bariatric surgery without the procedural risk when combined with lifestyle intervention.
The SELECT trial (2023) — 17,604 non-diabetic, overweight adults with established CVD — demonstrated a 20% reduction in MACE (major adverse cardiovascular events) with semaglutide, independent of weight loss. This is a paradigm shift for the drug class.
GLP-1 agonists improve insulin sensitivity, reduce fasting glucose, lower HbA1c, and improve lipid profiles in non-diabetic patients. These effects are partially independent of weight loss, suggesting direct metabolic signaling beyond appetite suppression.
Research shows 25–40% of weight lost on GLP-1 therapy can be lean mass. Our physicians pair every GLP-1 protocol with specific resistance training guidance, protein targets (1.6–2.2g/kg/day), and hormone optimization where appropriate to preserve muscle and maximize long-term metabolic outcomes.
Wilding JPH, et al. Once-weekly semaglutide in adults with overweight or obesity — STEP 1. N Engl J Med. 2021;384:989–1002.
Lincoff AM, et al. Semaglutide and cardiovascular outcomes in obesity without diabetes — SELECT trial. N Engl J Med. 2023;389:2221–2232.
Jastreboff AM, et al. Tirzepatide once weekly for the treatment of obesity — SURMOUNT-1. N Engl J Med. 2022;387:205–216.
Blundell J, et al. Effects of once-weekly semaglutide on appetite, energy intake, and body composition. Diabetes Obes Metab. 2017;19(9):1242–1251.
The thyroid governs metabolism, energy production, thermoregulation, and the function of virtually every organ system. Suboptimal thyroid function — even within conventional "normal" ranges — is associated with fatigue, weight gain, depression, cognitive impairment, and cardiovascular risk.
Most thyroid testing stops at TSH. PepLab physicians order the complete panel — TSH, Free T3, Free T4, Reverse T3, and thyroid antibodies — and interpret results in the context of your symptoms, not just the population reference range.
TSH, Free T3, Free T4, Reverse T3, TPO antibodies, and thyroglobulin antibodies. This is the panel that identifies conversion problems, autoimmune thyroid disease (Hashimoto's), and subclinical hypothyroidism that TSH-only testing consistently misses.
A landmark study by Celi et al. in JCEM demonstrated that patients on T3/T4 combination therapy showed significantly greater improvements in quality of life, mood, and cognitive function compared to T4 monotherapy — particularly in patients with poor T4-to-T3 conversion.
Chronic stress dysregulates the hypothalamic-pituitary-adrenal axis, producing patterns of cortisol dysfunction that drive fatigue, weight gain, immune suppression, and sleep disruption. PepLab uses 4-point salivary cortisol testing to identify and address these patterns.
Hashimoto's thyroiditis — an autoimmune attack on the thyroid — is the most common thyroid disorder in developed countries and among the most under-managed. Our protocols address both thyroid hormone optimization and the underlying inflammatory drivers.
Celi FS, et al. Metabolic effects of liothyronine therapy in hypothyroidism. J Clin Endocrinol Metab. 2011;96(6):1498–1508.
Panicker V, et al. Common variation in the DIO2 gene predicts baseline psychological well-being and response to combination thyroxine plus triiodothyronine therapy. J Clin Endocrinol Metab. 2009;94(5):1623–1629.
Garber JR, et al. Clinical practice guidelines for hypothyroidism in adults. Thyroid. 2012;22(12):1200–1235.
McAninch EA & Bianco AC. The history and future of treatment of hypothyroidism. Ann Intern Med. 2016;164(1):50–56.
Sleep is not a passive state. It is the biological mechanism through which your body repairs tissue, consolidates memory, regulates hormones, clears metabolic waste from the brain, and resets immune function. Chronic sleep insufficiency is associated with accelerated aging, hormonal decline, cardiovascular risk, and neurodegeneration.
PepLab's sleep protocols are clinician-guided, evidence-based, and integrated with your hormone picture — because the hormone-sleep relationship is bidirectional, and you cannot fix one without addressing the other.
Guidance on maximizing time in slow-wave (deep) sleep and REM — the two stages most critical for hormone release, tissue repair, and cognitive consolidation. Includes circadian alignment, temperature optimization, and light management.
Estrogen and progesterone have direct effects on sleep architecture. Progesterone has GABAergic properties (calming, sleep-promoting). Testosterone affects sleep apnea risk. Our protocols address sleep and hormones as a single integrated system.
CBT-I components, sleep restriction therapy, stimulus control, relaxation techniques, and chronotherapy — all with stronger long-term outcomes than pharmacological sleep aids per multiple RCTs.
Light therapy protocols, melatonin timing, temperature regulation, and the cortisol-melatonin seesaw — the biological levers that determine your circadian phase and sleep quality.
Leproult R & Van Cauter E. Effect of 1 week of sleep restriction on testosterone levels in young healthy men. JAMA. 2011;305(21):2173–2174.
Trauer JM, et al. Cognitive behavioral therapy for chronic insomnia: a systematic review and meta-analysis. Ann Intern Med. 2015;163(3):191–204.
Walker MP. Why We Sleep: Unlocking the Power of Sleep and Dreams. Scribner. 2017.
Van Cauter E, et al. Age-related changes in slow wave sleep and REM sleep and relationship with growth hormone and cortisol levels in healthy men. JAMA. 2000;284(7):861–868.
Chronic psychological stress is one of the most potent drivers of hormonal dysfunction, accelerated aging, and poor health outcomes. The bidirectional relationship between mind and body — particularly the HPA axis, cortisol, and inflammatory pathways — means that mental wellness practices are not optional additions to your protocol. They are clinical interventions.
PepLab's mind health library provides structured, evidence-based practices — from guided meditation to breathwork and stress regulation techniques — developed from neuroscience research and validated in clinical trials.
Structured meditation practices organized by goal: stress reduction, sleep preparation, cognitive focus, emotional regulation, and energy restoration. Protocols are based on MBSR, MBCT, and contemplative neuroscience research.
Box breathing, diaphragmatic breathing, and HRV biofeedback protocols with demonstrated effects on cortisol, autonomic nervous system state, and cardiovascular variability. Different techniques serve different physiological goals.
Chronic stress chronically elevates cortisol, which suppresses testosterone, thyroid, immune function, and impairs sleep. Mind health practices directly down-regulate the HPA axis, producing measurable hormonal benefits independent of other interventions.
Regular meditation practice has been associated with preserved telomere length, reduced neuroinflammation, and slower age-related cortical thinning. The evidence for meditation as a longevity intervention is now substantial enough to warrant clinical recommendation.
Hölzel BK, et al. Mindfulness practice leads to increases in regional brain gray matter density. Psychiatry Res. 2011;191(1):36–43.
Grossman P, et al. Mindfulness-based stress reduction and health benefits: A meta-analysis. J Psychosom Res. 2004;57(1):35–43.
Epel ES, et al. Meditation and vacation effects have an impact on disease-associated molecular phenotypes. Transl Psychiatry. 2016;6:e880.
Pascoe MC, et al. Mindfulness mediates the physiological markers of stress: systematic review and meta-analysis. J Psychiatr Res. 2017;95:156–178.
