Most people think of hair loss purely in terms of hormones and genetics. And they’re not wrong. DHT and your family history are the main drivers of pattern hair loss. However, there’s a growing body of evidence hinting to another factor that’s been hiding in plain sight. Oxidative stress is the process that contributes to skin ageing, cardiovascular disease and a host of other health problems. It also plays a significant role in damaging hair follicles, speeding up follicular miniaturisation and contributing to premature greying. What’s makes oxidative stress particularly exciting is that unlike your genetics, this is something you can actually influence. In this article we explore exactly what oxidative stress is, and how it damages your hair. We’ll also review the causes of oxidative stress and what you can do to prevent hair loss from it.
What is Oxidative Stress?
Oxidative stress is an imbalance between the production of free radicals and your body’s ability to neutralise them. Free radicals are unstable molecules that are missing an electron. To stabilise themselves they steal electrons from nearby cells which damages them. Your body actually produces free radicals naturally as byproducts of normal metabolism. In small amounts they play useful roles in immune defence and cell signalling. However, too many free radicals can outstrip your antioxidant defences. When that happens, the excess free radicals can damage cell membranes, proteins, fats and DNA. Over time this damage adds up and contributes to ageing and disease.
Your body’s has two main types of antioxidants. These are enzymes such as superoxide dismutase (SOD), catalase and glutathione peroxidase and compounds like vitamin E, vitamin C and glutathione. When these are overwhelmed, you get oxidative stress which can affect every single cell in your body.
How Does Oxidative Stress Affect Hair Follicles?
Hair follicles are metabolically active tissues that are particularly vulnerable to oxidative damage. They sit in the skin where they receive constant exposure to both internal and external sources of free radicals. Research has shown that oxidative stress damages hair follicles through several connected mechanisms:
- Dermal papilla cell damage: The dermal papilla is the control centre of the follicle. It determines what kind of hair the follicle makes and how long the growth phase lasts. Studies comparing dermal papilla cells from balding vs non-balding scalps have found that balding dermal papilla cells have higher levels of reactive oxygen species (ROS). This reduces cell function and increases markers of cell senescence (ageing). What’s really interesting is that when balding dermal papilla cells were exposed to oxidative stress they made higher levels of TGF-beta 1 and 2. Both of these are known hair growth inhibitors that promote premature entry into the catagen (regression) phase. This means that oxidative stress doesn’t just damage the follicle passively but also actively triggers it to produce signals that inhibit its own growth.
- Shortening of the growth phase: Oxidative stress pushes follicles out of the anagen (growth) phase and into catagen prematurely by impairing mitochondrial function within follicle cells. This reduces the energy available for hair production. When mitochondria become dysfunctional they produce even more ROS which creates a vicious cycle of increasing oxidative damage and declining follicle function. This is directly relevant to the hair growth cycle as the shorter the anagen phase, the thinner and shorter the hair.
- Amplifying DHT-driven miniaturisation: This is where oxidative stress connects directly to male and female pattern hair loss. Research increasingly suggests that oxidative stress and DHT work together. DHT promotes oxidative stress within the follicle and oxidative stress in turn boosts the effects of DHT on the dermal papilla. Studies have confirmed raised markers of oxidative damage in the dermal papilla cells of men with androgenetic alopecia. This means that for people with pattern hair loss, oxidative stress is likely making the hormonal damage worse. Addressing it could potentially slow the rate of miniaturisation even alongside hormone treatments.
- Perifollicular inflammation: Oxidative stress triggers low-level inflammation around the hair follicle. This chronic microinflammation in the upper portion of the follicle is present in androgenetic alopecia. It is thought to contribute to the fibrosis (scarring) that can make miniaturisation irreversible. This creates another harmful feedback loop where inflammation generates more free radicals which then generates more inflammation.
- Premature greying: Beyond hair loss, oxidative stress may also play a role in premature greying. Melanocyte stem cells in the follicle bulge region are responsible for hair pigmentation. Oxidative damage to these stem cells impairs their ability to renew themselves and produce melanin. As antioxidant defences decline with age, the built up oxidative damage to melanocyte stem cells is likely to be a key driver of hair greying.
What Causes Oxidative Stress in the Scalp?
Oxidative stress in the scalp comes from a combination of internal and external sources. These main causes of oxidative stress in the scalp ad hair follicles include:
- UV radiation: The scalp is one of the most sun-exposed areas of the body, particularly as hair thins. UV radiation generates significant amounts of free radicals in the skin which directly damage the follicular structures beneath.
- Pollution: Airborne pollutants including dust, nitrogen dioxide and polycyclic aromatic hydrocarbons generate free radicals on contact with the skin and scalp. Urban environments with high pollution are associated with a higher risk oxidative stress.
- Smoking: Cigarette smoke is one of the leading external triggers of free radicals. Smoking has been consistently linked to speeding up hair loss. There is also evidence of a relationship between smoking and severity of androgenetic alopecia.
- Psychological stress: Chronic stress increases cortisol and triggers inflammatory pathways that generate excess free radicals. This is one of the mechanisms by which stress can worsen hair fall and may explain why it triggers telogen effluvium.
- Poor nutrition: A diet low in antioxidants or deficient in zinc, selenium, vitamin C, vitamin E and iron impairs your body’s ability to neutralise free radicals. Nutritional deficiencies are also directly cause hair loss through other mechanisms so this is a double problem.
- Ageing: As we age the body makes more free radicals whilst simultaneously losing antioxidant capacity. This progressive imbalance is thought to drive much of the age-related decline in follicle function including the gradual thinning and loss of colour that occurs with time.
How to Protect Your Hair from Oxidative Stress
You can’t eliminate oxidative stress entirely as it’s a normal part of living. However there are a number of things you can do to reduce it and support your follicles’ ability to withstand it:
- Diet & nutrition: Focus on colourful fruits and vegetables (particularly berries, leafy greens, tomatoes and peppers), nuts, seeds, oily fish, whole grains and foods rich in vitamin C, vitamin E, selenium and zinc. Adequate protein and iron are also critical for maintaining follicle function. If blood tests reveal deficiencies in vitamin D, iron or zinc, targeted supplements can help.
- Stop smoking: This is one of the single most high yield thing you can do for your hair and everything else. Eliminating this major source of exogenous free radicals significantly reduces your overall oxidative load.
- Sun protection: Wearing a hat or using UV-protective scalp sprays outdoors can help reduce UV-induced oxidative damage. This is especially important for anyone with thinning hair where the scalp is more exposed.
- Stress management: Chronic stress drives both oxidative stress and inflammation. Regular exercise, adequate sleep, mindfulness and professional support for anxiety or depression can all help manage it better.
- Scalp care: Keeping the scalp clean and healthy helps reduce local inflammation and oxidative burden. Regularly wash with gentle shampoos and avoid harsh chemical treatments. Ketoconazole shampoos may also help by treating scalp inflammation.
Treatments That Target Oxidative Stress in Hair Loss
There is not a standard treatment specifically for treating oxidative stress at the hair follicle. However, several androgentic hair loss treatments also have antioxidant properties that may help protect follicles from oxidative damage. Possible treatments that may help target oxidative stress at the hair follicle include:
- Melatonin: This is one of the most powerful natural antioxidants and is increasingly used in topical hair loss treatments for this reason. Melatonin protects follicles from oxidative damage, extends the anagen phase and may help preserve hair colour. It is only available by prescription as part of compounded hair growth treatments formulations.
- Caffeine: In addition to its effects on follicle stimulation, caffeine acts as an antioxidant. It can help protect follicular cells from oxidative damage. Caffeine is available in many shampoos as well as prescription compound treatments.
- Minoxidil: This primarily promotes hair growth by increasing blood flow. However, minoxidil may also have protective effects on follicle function partly through improved oxygenation and nutrient delivery.
- DHT blockers: By reducing DHT’s action on the follicle, finasteride, dutasteride and spironolactone indirectly reduce the oxidative stress that DHT generates within the follicle.
- PRP therapy: Platelet rich plasma contains growth factors and cytokines that may help reduce local inflammation and support follicular repair.
- Emerging treatments: Several novel compounds are under investigation for hair loss have antioxidant properties as part of their mechanism. Deoxyribose sugar gel is thought to protect follicles partly by scavenging free radicals. The MLPH peptide which works via the IGF-1 pathway may also offer protect the hair follicles from oxidative stress.
Oxidative stress is an under appreciated contributor to hair loss that works alongside and amplifies the effects of DHT, genetics and ageing on the hair follicle. It damages dermal papilla cells, shortens the growth phase, accelerates miniaturisation, drives perifollicular inflammation and contributes to premature greying. Although your genetics and hormones are the primary drivers of pattern hair loss, the environment you create for your follicles through diet, lifestyle, scalp care and targeted treatments can actually influence how much oxidative damage they sustain. Addressing oxidative stress won’t replace the need for using hair loss treatments but it can support their effectiveness and help protect the follicles you still have.
We provide personalised hair loss treatments for women and men through our online skin clinic. Our doctors create custom hair growth treatments using actives such as Minoxidil, Finasteride, Dutasteride, Spironolactone, Melatonin, Caffeine and Tretinoin where appropriate for each and every patient. Start your virtual consultation and begin your journey to great hair today.
This article is intended for general informational purposes only and is not a substitute for medical advice, diagnosis or treatment. Always consult a qualified medical professional with any concerns about your hair or treatment options.
