While it is inevitable everyone will experience some form of hair loss at some point in their life, there are plenty of lifestyle factors and scientific reasons that play into our strands leaving the nests we've created for them. A stressful chapter of life, malnutrition or deficiencies, illnesses, traumas and so many other things can cause our hair to begin to fall out.
It turns out hair loss is a part of our daily program. It's totally normal for us to be losing a few strands each day, but how do we know when we've passed the threshold from normalcy to problematic hair loss? We spoke to a dermatologist and a trichologist about the varying dilemmas responsible for thinning out our strands and how to proactively put up a good fight. Keep reading to learn more about the 12 major causes of hair loss, what's happening behind the scenes, and how to bounce back given the circumstances.
Meet the Expert
- Dr. Joshua Zeichner is the Director of Cosmetic and Clinical Research in Dermatology and an Associate Professor of Dermatology at the Mount Sinai Hospital in New York City.
- Shab Reslan is a certified trichologist and stylist. She hosts the Hair Like Hers podcast and offers virtual hair and scalp consultations. She is based in New York City.
Pregnancy and Childbirth
One of the most frequently talked about and less frequently explained reasons for hair loss is giving birth. Women get this beautiful head of hair during pregnancy, with little to no shedding at all, but of course that doesn't last long. A few months into the postpartum period and it all comes falling out by the handful. Why does this happen?
There are three phases to our hair's life cycle: anagen (growth), catagen (transition), and telogen (resting). During pregnancy, the hair remains in the anagen phase due to hormonal changes. Once the baby is born and hormones shift yet again, the hair moves into the catagen and telogen phases. All that hair you accumulated is finally ready to shed itself as it would've normally. Of course, having it all happen at once can feel worrisome. Don't worry mama, in a few months your hormones will balance out again and your hair's growth will too.
"Fighting genetic hair loss early on is the key to altering what might seem inevitable," expert Shab Reslan assures us. Androgenetic alopecia (male or female pattern hair loss) can occur as early as your 20s and 30s, especially if it's a known issue for others in your family line. Beginning a routine that focuses on your scalp and overall health is the key to fighting back against heredity hair loss, according to Reslan. It could include a multitude of treatments from supplements, to the right products, and diet (all things we'll cover as you read on).
"At any point, if you started to notice more than the usual amount of hair being shed throughout your home or in your shower, visit your dermatologist for evaluation," says Dr. Zeichner. "You will get a thorough examination of your scalp itself and likely some blood work.
"Hair thinning is multifactorial. It is a complete [myth] that your hair density is determined by your mother’s father. Hair thinning is a common issue in both men and women across all ethnicities."
Neglected Scalp Health
"Inflammation is not our skin's friend," says Dr. Zeichner. "Even chronic, low-grade inflammation can interfere with healthy hair follicle functioning." Sadly, interfering with our hair follicles is a pretty easy mistake to make. "Infrequent shampooing and product buildup from dry shampoo, leave-ins, or improper rinsing can really block the follicle opening," says Reslan. "Over time this causes the follicle to become inactive and create a permanent effect." Not taking care of our scalps can exacerbate issues like dandruff and psoriasis, so following Reslan's advice by washing frequently and rinsing thoroughly to avoid product build-up is key to taking preventative measures against hair loss.
Dr. Zeichner also reminds us that hair thinning is a scalp issue rather than a true hair issue. "When hair follicles are not working the way that they should, hairs may grow thin or fall out," he says. "Look for hair and scalp serums that work directly on the follicles, like the Grande Cosmetics GrandeHair Enhancing Serum ($125) which contains a specialized peptide that helps support healthy functioning of your hair follicles."
Note the difference between hair thinning and hair loss as well. "Hair thinning is when your hair grows-in weaker due to improper scalp conditions or improper diet and underlying ailments," Reslan says. "Hair loss is when hair is falling out completely either due to a reactionary cause such as stress or with chronic hair loss over time as the follicle slowly shrinks and no longer grows hair."
Medical issues or underlying diseases may be playing a part in any hair loss you're experiencing. "Thyroid issues are definitely the number one leading illnesses that are responsible for hair loss," says Reslan. Other hormonal issues such as Polycystic Ovary Syndrome could also be a part of your hair woes, as can any autoimmune disease. Reslan states that even health issues such as diabetes—"which is responsible for poor circulation in the body"—can cause scalp issues and, in turn, affect your hair's growth.
The good news is, treating any underlying medical issue will help reverse this unwanted side effect. Dr. Zeichner tells us that if the underlying medical issue is corrected, thinning hair will often correct itself as well. "The process takes several months," he says, "so it is important to be patient."
If you love a coiffure, listen up. Styling your mane is an expressive outlet, but if you aren't delicate with your strands you may be on a path towards hair loss. Reslan tells us that too much tension, and excessive or constant pulling of the hair can lead to something called Traction Alopecia. Styles that are extremely tight like "snatched" ponytails, braids, and even extensions can lead to your hair falling out. Using spiral hair ties or silk scrunchies can be a gentler alternative to pulling your hair back without breakage. It's also helpful to make sure you're using the right type of hair brush, especially when heat styling.
Heat and Chemical Treatments
Over-processing your hair by bleaching and dyeing it too frequently can cause serious breakage. Talk to your colorist about your hair health goals as well as your color goals so they can approach your color goals responsibly and respectfully. Taking a softer route to blonde hair via balayage (which requires less frequent visits), not sitting under the hair dryer during processing, and using supportive, hydrating products like Olaplex, can all make a huge difference.
Daily heat styling can also create problems for your hair, making it more brittle, damaged, and prone to breakage. Using heat protectants before styling, getting frequent trims, and giving yourself a few days off between heat styling will work together to have a major impact in preventing hair loss.
Dr. Zeichner suggests over-the-counter shampoos and conditioners that help volumize the hair. Stay away from products designed for dry or coarse hair, he warns, because they tend to be too heavy for thinning hair, weighing it down, and making it look more limp and flat.
Vitamins and minerals play an important role in maintaining our hair's health. The most common deficiencies linked to hair loss are in vitamin B12, biotin, folate, and riboflavin. Some of these deficiencies, like biotin, may have other noticeable side effects, like splitting nails. Thankfully, there are supplements that may help us correct these imbalances. For this reason alone, the case for taking a daily multivitamin has never looked better.
"Consider oral supplements with ingredients that provide the hairs with building blocks for optimal functioning. For example, Nutrafol contains botanical ingredients that have been clinically studied and shown to enhance hair growth with regular use."
Lack of Protein
There are reverse effects to certain dietary efforts that could cause unfavorable results, like hair loss. "Vegans and vegetarians generally notice weaker and finer hair growth over time," says Reslan. "The lack of essential amino acids in non-animal protein diets has become a big issue, especially with the rise of veganism." Getting an appropriate amount of protein worked into our diets is essential for strong and healthy hair growth, Reslan tells us.
Rapid weight loss and calorie restrictions can also lead to hair thinning and hair loss, so it's extremely important to consult a dietitian that can help you create a dietary plan specific to your body's needs before you start restricting calories.
Physical or Emotional Trauma
Any type of trauma you've experienced in your life can also be a leading culprit to hair loss. Physical or emotional traumas can be associated with rapid hair loss, though Dr. Zeichner says you may not see your strands fall out until 3 to 5 months later. "This condition is called telogen effluvium. It is unclear why," he says, "but the stressful events send the hairs into a degenerative phase where they are rapidly shed." Thankfully, telogen effluvium is reversible and can be treated, as can any type of sudden hair loss.
There are two types of hair loss: chronic hair loss and sudden hair loss. Chronic hair loss occurs slowly and usually begins with the thinning of the hair over a prolonged period of time. Sudden hair loss occurs quickly and all at once, usually due to stress and inflammation.
There are plenty of hormonal changes a woman experiences in her life. Postpartum, menopause, IVF treatment, and coming on or off of birth control are all life events that create an imbalance of hormones and lead to hair loss. "The estrogen levels in the body will either increase or become regulated and through that process, hair loss in the frontal area of the head is very common," Reslan tells us. "If your hormone levels don’t become balanced, you may experience chronic hair loss and will not see a reversal until your levels are regulated."
When we are undergoing stress, Reslan explains that the body shuts down the least important systems in an effort to heal itself, and that unfortunately includes the hair system. "Any situation that causes high stress will almost always have an effect on the hair," says Reslan.
Stress has been a known link to inflammation in the body and immunity issues, and apparently these factors link to hair loss as well. Reslan informs us that reactionary hair loss, which is normally caused by stress and inflammation in the body, typically shows itself suddenly. "This type of sudden hair loss is reversible and temporary, only if your stress levels and overall health return back to normal in a timely matter," she says. "Prolonged episodes of stress and a stressful lifestyle can eventually cause permanent damage to your follicles. I always recommend my clients that are dealing with high stress levels to take natural supplements including Ashwagandha and CBD to help calm their nerves and relax them throughout the day. "
Some medications are knowingly linked to hair loss as a side effect. But when weighing the odds against one another, that medication or treatment may be way more important to our overall health. So what are we left to do about our hair?
Talk to your doctor about the longevity of your medications. "Prolonged use of medications known to cause hair loss can result in permanent effects," Reslan says. When hair follicle cells are challenged for long periods of time, Reslan tells us it may cause the follicle to shrink and become inactive.
If you've completed treatment as advised and are still struggling to see your hair grow as it once did, seek out a medical professional to help you identify the internal and external factors at play.
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