10 Evidence-Based Ways to Naturally Increase Your Endorphins

By Yoon Hang Kim, MD, MPH Board-Certified in Preventive Medicine | Integrative & Functional Medicine Physician

Endorphins are among the most powerful natural molecules your body produces — and yet most people have only a vague sense of what they actually are or how to harness them intentionally. In integrative and functional medicine, understanding these endogenous opioid peptides isn't just academic; it's clinically actionable.

β-endorphin, the most studied member of the endorphin family, is a 31-amino-acid peptide derived from proopiomelanocortin (POMC). It is produced primarily by POMC-expressing neurons in the hypothalamic arcuate nucleus and by the anterior pituitary gland. β-endorphin binds to μ-opioid receptors (MORs), the same receptors targeted by exogenous opioids like morphine — but without the risk of dependency, respiratory depression, or tolerance that accompany pharmaceutical opioids.

Endorphins don't work alone. They operate alongside endocannabinoids, dopamine, oxytocin, and HPA axis stress-regulation pathways to modulate pain perception, mood, immune function, and social bonding. This is why different people respond to different "mood-lifting" strategies, and why an integrative approach — stacking multiple endorphin-promoting interventions — tends to produce the most robust and sustainable results.

Here are 10 evidence-based strategies to naturally increase your endorphin levels, organized from strongest to moderate evidence — with specific guidance for those who cannot tolerate exercise due to post-exertional malaise (PEM).

1. Exercise — Particularly High-Intensity and Sustained Aerobic Activity

The "runner's high" is not a myth. A landmark 2008 PET neuroimaging study by Boecker and colleagues provided the first direct evidence of opioid release in the human brain during exercise. The study demonstrated increased opioid binding in prefrontal and limbic regions — areas known to play a key role in emotional processing — that directly correlated with subjective euphoria ratings (Boecker et al., Cereb Cortex, 2008;18(11):2523–2531).

A subsequent 2017 PET study from the Turku PET Centre found that high-intensity interval training (HIIT) produced significant endorphin release in the thalamus, insula, orbitofrontal cortex, hippocampus, and anterior cingulate cortex — brain regions controlling pain, reward, and emotion (Saanijoki et al., Neuropsychopharmacology, 2018;43(2):246–254).

Exercise above the anaerobic threshold consistently elevates circulating β-endorphin levels. The lactate threshold appears to serve as a critical trigger point, and both incremental graded exercise and HIIT produce significant β-endorphin elevations, typically peaking within 15 minutes of exercise cessation (Goldfarb & Jamurtas, Sports Med, 1997;24(1):8–16).

Clinical takeaway: Moderate-to-vigorous aerobic exercise — running, cycling, swimming, rowing — for at least 30–60 minutes appears to be the most reliable way to trigger measurable endorphin release. Even a brisk walk at a pace that challenges your cardiovascular system can be effective. The key is sustained effort beyond the comfort zone.

Important caveat — Post-Exertional Malaise (PEM): If you live with ME/CFS, Long COVID, fibromyalgia, POTS, or any condition where PEM is part of your clinical picture, exercise — the single strongest evidence-based strategy for endorphin release — can be actively harmful. PEM is a disproportionate worsening of symptoms following physical or mental exertion, with onset typically delayed 12–48 hours, lasting days to weeks. Two-day cardiopulmonary exercise testing (CPET) studies have documented objective declines in oxygen consumption and work capacity during PEM, confirming this is physiological, not psychological (Barhorst et al., Pain Med, 2022;23(6):1144–1157). The 2021 NICE guidelines for ME/CFS concluded that graded exercise therapy (GET) should not be offered, finding that programs based on fixed incremental increases in physical activity can cause serious harm. The U.S. CDC has similarly warned that standard exercise recommendations for healthy people can be harmful for people with ME/CFS. If PEM is part of your picture, this does not mean you are locked out of your body's endorphin system — it means the remaining nine strategies in this article become your primary toolkit. Read on, and see the dedicated PEM guidance at the end of this article.

2. Social Laughter

This is one of the more elegant findings in recent neuroscience. Manninen et al. (2017) used PET imaging to demonstrate that social laughter — laughing together with close friends — significantly increased endogenous opioid release in the thalamus, caudate nucleus, and anterior insula. The researchers also found an interesting individual difference: the more opioid receptors a participant had in their brain, the more they laughed during the experiment (Manninen et al., J Neurosci, 2017;37(25):6125–6131).

The study concluded that endorphin release induced by social laughter may be an important pathway supporting the formation, reinforcement, and maintenance of social bonds. Laughter is highly contagious, and the endorphin response can spread through large groups who laugh together, a mechanism that may have evolved to strengthen social cohesion.

Clinical takeaway: Social laughter is more powerful than solitary laughter. Watch comedies with friends, join group activities that make you laugh, or simply prioritize social time with people who bring you joy. It's not just "good for the soul" — it's measurably good for your neurochemistry. For those managing PEM, social laughter — even via video call from bed — is one of the most potent zero-exertion endorphin strategies available.

3. Music-Making, Singing, and Dancing

Robin Dunbar and colleagues at the University of Oxford have built a compelling body of evidence showing that active musical performance — singing, dancing, and drumming — elevates pain thresholds (a validated proxy for endorphin release), whereas passive listening does not produce the same effect (Dunbar et al., Evol Psychol, 2012;10(4):688–702).

Weinstein et al. (2016) extended these findings to large-scale group singing. Using a community choir structure that periodically aggregated into a 232-person "megachoir," they showed that singing in both small (20–80 person) and large group contexts raised pain thresholds and increased self-reported social bonding. Critically, the endorphin-mediated bonding effect scaled up — the large group showed comparable closeness gains to the small groups, suggesting that music may serve as a mechanism for bonding beyond the limits of one-to-one social interaction (Weinstein et al., Evol Hum Behav, 2016;37(2):152–158).

Synchronized exertive activity (such as rowing in rhythm) elevates pain thresholds significantly more than non-synchronized exertion, suggesting that the rhythmic, coordinated element of music-based activities adds an additional layer of endorphin facilitation (Tarr et al., Front Psychol, 2014;5:1096).

Clinical takeaway: The endorphin benefit comes from active participation — singing, drumming, dancing — not from passive listening alone. Group settings amplify the effect. Join a choir, take a dance class, drum in a circle. This is one of the few interventions that simultaneously boosts endorphins and strengthens social bonds, addressing two pillars of health at once. For those with PEM, even gentle humming, quiet singing, or light hand drumming may engage this pathway without crossing the exertional threshold — but individualize carefully, as even singing can trigger PEM in severely affected individuals.

4. Meditation and Mindfulness Practice

Harte et al. (1995) conducted a pivotal study comparing 11 elite runners and 12 highly trained meditators, matched in age, sex, and personality. Both groups showed elevated mood after their respective activities with no significant difference between groups. Corticotropin-releasing hormone (CRH) — which is significantly associated with circulating β-endorphin — was elevated after both running and meditation. The researchers concluded that physical exercise is not a prerequisite for CRH release or the associated endorphin cascade (Harte et al., Biol Psychol, 1995;40(3):251–265).

Research on the psychoneuroimmunology of meditation has revealed that the prefrontal cortex acts as a "functional connectome," simultaneously providing excitatory inputs to the hypothalamic arcuate nucleus to release β-endorphin, while also activating the right caudate nucleus (emotional and focused attention regulation) and right lentiform nucleus (reward-like experience) (Magan & Yadav, Ann Neurosci, 2022;29(2-3):170–176).

A randomized controlled trial on Heartfulness meditation demonstrated that 30 days of guided meditation practice enhanced the secretion of both oxytocin and beta-endorphins while decreasing cortisol levels — a neuroendocrine profile shift toward emotional resilience and stress buffering (Philip ST et al., Medicine (Baltimore), 2025; PMID 41305815).

Clinical takeaway: You don't need a specific style. Heart-centered, mindfulness, and transcendental meditation practices have all shown positive effects. The common mechanism appears to involve deep relaxation and sustained attention that shift the body's stress-hormone balance. Even 20–30 minutes daily can produce measurable effects. For clients with PEM, this is a cornerstone intervention — body scan meditation, loving-kindness practice, and breathwork can all be performed lying down, making them accessible even during post-exertional crashes.

5. Acupuncture

The endorphin-releasing mechanism of acupuncture is among the best-characterized in complementary medicine. Studies dating back to the 1970s established that acupuncture stimulation increases the release of endogenous opioid peptides in the central nervous system, inhibiting pain perception — an effect that can be reversed by the opioid antagonist naloxone, confirming the opioid-mediated mechanism (Yang & Kok, Am J Chin Med, 1978;6(3):203–205).

Han's seminal work demonstrated that electroacupuncture (EA) at different frequencies releases different opioid peptides: EA at 2 Hz accelerates the release of enkephalin, β-endorphin, and endomorphin (activating mu- and delta-opioid receptors), while EA at 100 Hz selectively increases dynorphin release (activating the kappa-opioid receptor). A combination of both frequencies produces simultaneous release of all four opioid peptides, resulting in maximal therapeutic effect — a finding verified in clinical studies on chronic low back pain and diabetic neuropathic pain (Han, Neurosci Lett, 2004;361(1-3):258–261).

The serotoninergic descending inhibitory pathway also collaborates with endogenous opiates in acupuncture-mediated analgesia, and the neuro-endocrine-immune network activated by acupuncture extends the benefits beyond simple pain relief (Lin & Chen, Am J Chin Med, 2008;36(4):635–645). Multiple studies have also demonstrated acupuncture's benefit specifically in ME/CFS, showing improvements in fatigue severity, pain, and overall function — making it one of the most clinically relevant interventions for this population.

Clinical takeaway: Acupuncture — particularly electroacupuncture using combined low and high frequencies — is one of the most targeted and well-characterized methods for stimulating endogenous opioid release. For clients dealing with chronic pain, neuropathy, or conditions where pharmaceutical opioid avoidance is critical, acupuncture offers a powerful integrative tool. For clients with PEM, acupuncture is arguably the most important single intervention in this list: it directly stimulates the full spectrum of endogenous opioid release entirely independent of physical exertion, and the client rests passively during treatment.

6. Sunlight and UV Exposure (With Important Caveats)

This is one of the more fascinating endorphin pathways in recent research. Fell, Fisher, and colleagues at Massachusetts General Hospital (Harvard Medical School) identified that UV radiation causes the synthesis and release of beta-endorphin directly in the skin through a p53-mediated induction of the POMC gene in epidermal keratinocytes. Their landmark study, published in Cell, found that chronic UV exposure raised circulating β-endorphin levels and produced opiate-like effects, including measurable addictive behavior — UV-habituated mice exhibited withdrawal symptoms when β-endorphin activity was blocked by naloxone (Fell GL et al., Cell, 2014;157(7):1527–1534).

A subsequent human study confirmed that even minimal UV-B exposures increased β-endorphin expression in epidermal keratinocytes in vivo, providing the first in-vivo human confirmation of the pathway identified in animal models (Wäster et al., J Photochem Photobiol B, 2016;159:24–29).

Intriguingly, visible UV-free blue light (453 nm) has also been shown to induce significant increases in both local and systemic β-endorphin production through a nitric oxide–dependent mechanism, potentially offering a lower-risk alternative to UV exposure (Opländer et al., J Photochem Photobiol B, 2019).

Clinical takeaway: Brief, protected morning or late-afternoon sunlight exposure (15–20 minutes) with appropriate sun protection is a reasonable way to support natural β-endorphin production while also facilitating vitamin D synthesis. However, the skin cancer risks of excessive UV exposure must be weighed carefully. This is not a recommendation for prolonged unprotected sun exposure or tanning. The blue-light pathway represents an intriguing area for future clinical application. For clients with PEM, morning sunlight can be taken seated or reclined outdoors, doubling as circadian rhythm support — which is often disrupted in ME/CFS and Long COVID.

7. Heat Therapy and Sauna

Heat exposure triggers endorphin release through a mechanism similar to, but distinct from, exercise-induced endorphin production. The thermal stimulus activates the hypothalamic-pituitary axis in a way that temporarily downregulates the stress response. Multiple studies have documented that sauna heat exposure causes a significant increase in beta-endorphin levels (Masuda et al., Psychother Psychosom, 2005;74(5):288–294).

In a study of clients with fibromyalgia, a far-infrared "Waon therapy" protocol (60°C for 15 minutes followed by 30 minutes of warmed rest) produced a significant reduction in pain — roughly a 50% decrease on the Visual Analog Scale, with some participants reporting reductions of up to about 70% after the first session — and the benefit persisted well beyond the treatment period (Matsushita et al., Intern Med, 2008;47(16):1473–1476).

Heat-based approaches have also shown promise in mood disorders. A randomized, sham-controlled trial found that a single session of whole-body hyperthermia produced a rapid antidepressant effect in adults with major depressive disorder, with reductions on the Hamilton Depression Rating Scale that remained significant through six weeks of follow-up (Janssen et al., JAMA Psychiatry, 2016;73(8):789–795).

Clinical takeaway: Both traditional and infrared sauna sessions of 20–30 minutes at therapeutic temperatures (120–175°F depending on type) can reliably trigger endorphin release. For clients with chronic pain conditions like fibromyalgia, regular sauna therapy may offer a meaningful adjunct to other treatments. Always ensure adequate hydration and appropriate medical clearance, especially for clients with cardiovascular conditions. For those with PEM, POTS, MCAS, or dysautonomia, proceed with caution: many of these individuals have impaired thermoregulation, and heat can trigger mast cell degranulation or orthostatic symptoms. Start with infrared sauna at lower temperatures (100–125°F) for shorter durations (10–15 minutes), or consider a warm (not hot) Epsom salt bath as a gentler alternative that still engages mild heat-mediated endorphin pathways.

8. Spicy Food and Capsaicin

When you eat spicy food, capsaicin binds to TRPV1 receptors — pain and heat-detecting receptors found throughout the mouth, gut, and nervous system. The resulting pain signal prompts the brain to release beta-endorphin as a compensatory analgesic response. Experimental work has demonstrated that capsaicin can elevate beta-endorphin concentration in cerebrospinal fluid, an effect linked to pain relief and feelings of pleasure (Bach FW et al., Regul Pept, 1995;59(1):79–86; reviewed in Zhang et al., Soc Cogn Affect Neurosci, 2025;20(1):nsaf040).

The TRPV1 receptor pathway was the subject of the 2021 Nobel Prize in Physiology or Medicine (awarded to David Julius and Ardem Patapoutian), underscoring its fundamental importance in sensory biology. The phenomenon of enjoying spicy food has been described in the research literature as "benign masochism" — the learned enjoyment of a sensation the body initially registers as a threat, driven by the reward of the subsequent endorphin and dopamine release.

A 2025 study published in Social Cognitive and Affective Neuroscience confirmed that spicy food intake suppressed pain perception in human subjects and linked this analgesic effect to opioid receptor activation and beta-endorphin release (nsaf040).

Clinical takeaway: Incorporating moderate amounts of capsaicin-containing foods — chili peppers, cayenne, hot sauces — into the diet can provide a mild endorphin boost. This is a simple, low-risk, zero-exertion intervention that can complement other strategies. For clients with GERD, IBS, MCAS, or other GI sensitivities, titrate slowly and individualize.

9. Dark Chocolate and Cacao

Dark chocolate contains several neuroactive compounds associated with mood, including phenylethylamine (PEA) — a compound that promotes dopamine signaling — and theobromine, a mild stimulant related to caffeine. Beyond its specific constituents, the palatability of chocolate itself appears to engage the endogenous opioid system. Controlled studies using the opioid blocker naloxone have shown that blocking opioid receptors reduces both the pleasantness and the consumption of sweet, high-fat foods, supporting a direct opioid-mediated component to the pleasure these foods provide (Drewnowski et al., Am J Clin Nutr, 1995;61(6):1206–1212).

A 2019 cross-sectional study published in Depression and Anxiety found that people who consumed any amount of dark chocolate during two 24-hour periods were 70% less likely to report symptoms of depression than those who ate no chocolate. The top 25% of dark chocolate consumers were the least likely to report depressive symptoms. Importantly, this association was specific to dark chocolate — not milk chocolate (Jackson et al., Depress Anxiety, 2019;36(10):987–995).

Clinical takeaway: A small serving (1–2 ounces) of high-quality dark chocolate (≥70% cacao) can be a reasonable adjunct for mood support. The higher the cacao content, the greater the concentration of PEA, theobromine, and flavanols. This is not a license for overconsumption — the sugar and caloric content of chocolate must be considered in the context of each client's overall dietary strategy.

10. Physical Touch and Human Connection

Physical contact — hugging, holding hands, massage — triggers endorphin release alongside oxytocin, another hormone released by the pituitary gland that is deeply involved in social bonding and trust. While the direct PET-level evidence for massage-specific endorphin release is less robust than for exercise or laughter, clinical studies consistently show that massage therapy reduces cortisol while elevating mood-related neurochemistry, with the endogenous opioid system implicated as a plausible mediator (Field et al., Int J Neurosci, 2005;115(10):1397–1413).

The brain opioid theory of social attachment (BOTSA) supports the broader concept that endorphin signaling is fundamental to mammalian bonding. PET imaging studies have demonstrated that routine social behavior activates endogenous opioid signaling, reinforcing the idea that human connection is not just emotionally important but neurochemically essential.

Clinical takeaway: Regular physical affection with loved ones, professional massage therapy, and even acupressure are all practical ways to support endorphin tone. For clients who are isolated or lack regular physical contact, this represents an underappreciated area of intervention — social prescribing, therapeutic massage, and community-based group activities can all help fill this gap. For those with PEM, gentle massage and acupressure are excellent options, but deep tissue work can itself trigger PEM in sensitive individuals — keep it light.

A Special Note for Those with Post-Exertional Malaise (PEM)

If you live with ME/CFS, Long COVID, fibromyalgia, POTS, mast cell activation syndrome (MCAS), or any condition where PEM is part of your clinical picture, this section is for you.

PEM — the hallmark symptom of ME/CFS — is a disproportionate, delayed worsening of symptoms following physical or mental exertion. It is not ordinary fatigue. Two-day CPET studies have documented objective, measurable declines in oxygen consumption and work capacity during PEM episodes, confirming that this is a physiological phenomenon (Barhorst et al., Pain Med, 2022;23(6):1144–1157). The 2021 NICE guidelines for ME/CFS concluded, after extensive evidence review, that graded exercise therapy should not be offered, and the U.S. CDC has warned that standard exercise recommendations can be harmful for this population (NICE guideline NG206, October 2021; Vink & Vink-Niese, Healthcare, 2022;10(5):898).

The good news: exercise is only one of ten pathways to endorphin release described in this article, and several of the remaining nine require zero physical exertion. The goal for those with PEM is not to replicate the intensity of a runner's high. It is to consistently and gently support endogenous opioid tone through multiple accessible pathways — improving pain modulation, mood, sleep quality, and stress resilience without paying for it with a crash.

Your PEM-Safe Endorphin Toolkit, by Exertional Cost

Zero exertion — can be done from bed:

• Acupuncture is arguably the single most important endorphin intervention for this population. It directly stimulates the full spectrum of endogenous opioid release — β-endorphin, enkephalin, endomorphin, and dynorphin — through well-characterized neural pathways, entirely independent of physical exertion. The client rests passively during treatment. Electroacupuncture using combined low (2 Hz) and high (100 Hz) frequencies produces the broadest opioid peptide release. Multiple studies have demonstrated acupuncture's benefit specifically in ME/CFS, showing improvements in fatigue severity, pain, and overall function.
• Meditation and breathwork engage the CRH–β-endorphin cascade without any physical demand. Body scan meditation, loving-kindness practice, and breathwork can all be performed lying down, making them accessible even during post-exertional crashes. The Harte et al. (1995) study demonstrated that meditation produced mood elevation comparable to running, with no significant difference between groups, and a 2025 randomized controlled trial found that a 30-day meditation program raised serum β-endorphin and oxytocin while lowering cortisol (Philip ST et al., Medicine (Baltimore), 2025; PMID 41305815).
• Social laughter — with close friends or family, even via video call — triggers PET-confirmed opioid release. Watching a comedy together or sharing funny videos is a zero-exertion strategy that simultaneously combats the social isolation that so often accompanies chronic illness.
• Dark chocolate and spicy food engage endorphin pathways through dietary mechanisms that require no exertion whatsoever. A square of high-cacao dark chocolate and a capsaicin-containing meal offer modest but real neurochemical support.
• Morning sunlight (10–15 minutes, seated or reclined outdoors) supports β-endorphin production via the UV-POMC pathway in skin keratinocytes while also supporting circadian rhythm regulation.
• Gentle physical touch — hand massage, acupressure from a partner, or simply holding hands — engages endorphin and oxytocin pathways simultaneously.

Low exertion — titrate within your energy envelope:

• Gentle humming or quiet singing may engage the endorphin pathway Dunbar and colleagues have documented for active musical participation, at a much lower exertional cost than full-voice singing or dancing. Individualize carefully.
• Infrared sauna at lower temperatures (100–125°F for 10–15 minutes) or a warm Epsom salt bath may trigger mild heat-mediated endorphin release. Use caution with POTS, MCAS, or dysautonomia — impaired thermoregulation and mast cell sensitivity can make heat a double-edged sword.

The Pacing Principle Applied to Endorphin Strategies

The same pacing principles that protect you from PEM in daily activities should be applied to your endorphin-supporting practices:

• Stay within your energy envelope. Use heart rate monitoring if available. If your anaerobic threshold is low, even gentle yoga or tai chi may cross it.
• Prioritize passive and receptive modalities — acupuncture, meditation, laughter, warmth, touch — over active ones.
• Stack multiple low-cost strategies rather than relying on a single high-cost one. A day that includes 15 minutes of morning sunlight, a meditation session, a square of dark chocolate, and a phone call that makes you laugh has engaged at least four distinct endorphin pathways without crossing the exertional threshold.
• Rest proactively before and after any endorphin-supporting activity that involves even mild physical engagement.
• Track your responses. Some clients find that certain modalities — particularly heat — can occasionally trigger PEM-like responses. Journaling your symptom patterns after trying each strategy helps identify your personal best-tolerated toolkit.

Putting It All Together: An Integrative Approach

The beauty of these strategies is that they are complementary, not competing. A client who exercises regularly, meditates, laughs with friends, sings in a group, enjoys dark chocolate, and receives regular acupuncture is stacking multiple endorphin-promoting interventions across different neurochemical pathways. For those with PEM, the same stacking principle applies — simply with a different selection of modalities.

For clients dealing with chronic pain, fibromyalgia, ME/CFS, Long COVID, depression, anxiety, or conditions where pharmaceutical opioid use is a concern, this integrative toolkit offers a meaningful alternative or adjunct. The evidence is strongest for exercise and social laughter (both confirmed at the PET imaging level), followed by acupuncture, music-making, and meditation — all of which have solid mechanistic and clinical support.

The key is consistency. β-endorphin may remain dysregulated for weeks after severe stress, which is why recovery plans should prioritize gradual, sustainable interventions rather than "quick fixes." Build these practices into your daily and weekly rhythm, and the cumulative neuroendocrine benefits can be profound.

References

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2. Saanijoki T et al. "Opioid release after high-intensity interval training in healthy human subjects." Neuropsychopharmacology. 2018;43(2):246–254.
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About Dr. Kim

Yoon Hang Kim, MD, MPH, is board-certified in Preventive Medicine with over 20 years of experience in integrative and functional medicine. He completed his fellowship training at the University of Arizona under Dr. Andrew Weil and holds additional certifications in preventive medicine, medical acupuncture, and integrative and holistic medicine. Dr. Kim specializes in low dose naltrexone (LDN), autoimmune conditions, chronic pain, integrative oncology, fibromyalgia, chronic fatigue syndrome, mast cell activation syndrome (MCAS), and mold toxicity. He is the author of 3 books and over 20 published articles. To learn more, visit www.yoonhangkim.com or www.directintegrativecare.com.