Jun 10, 2025
What’s Causing Your Hair to Fall Out? Everything You Need to Know About Hair Loss
A science-backed guide to the real reasons behind hair loss and how targeted testing and the right supplements can help you grow it back.
Health Hacks
Written by
Mito Team
You notice more strands in your brush. The shower drain fills up faster. Maybe your part looks a little wider. Hair loss can feel unsettling, and it’s often a signal that your body is missing something important.
Let’s break down the most common causes of hair loss—and how key nutrients like iron, magnesium, and zinc support healthy, consistent regrowth.
How Hair Actually Grows (And Falls Out)
Hair follows a natural growth cycle with three key phases:
Anagen (growth): lasts 2 to 7 years
Catagen (transition): lasts a few weeks
Telogen (resting/shedding): lasts 3 to 4 months
Losing 50 to 100 hairs per day is normal. But when stress, illness, or deficiencies disrupt this cycle, a large percentage of hairs can enter the shedding phase all at once. This is called telogen effluvium, and it’s one of the most common (and reversible) causes of diffuse hair loss.
Common Causes of Hair Loss: A Deeper Look
It’s easy to think that age or stress is the reason for thinning hair, but the truth is, there are lots of different causes, and each one has its own solution.
1. Hereditary Hair Loss
Androgenetic Alopecia is the most common cause of hair loss worldwide. You might have heard it called male-pattern or female-pattern baldness. It mostly comes down to genetics and hormones.
Basically, some people are more sensitive to a hormone called DHT, which comes from testosterone. Over time, this sensitivity causes hair follicles to get smaller and can lead to hair loss.
In women: Thinning along the crown or widening part
In men: Receding hairline or bald spots
You can’t change your genes, but there are things you can do to help slow down hair loss. Taking care of things like nutrient deficiencies and hormone imbalances can really make a difference.
2. Hormonal Imbalances
Changes in hormone levels—during pregnancy, after giving birth, or during menopause—affect your hair growth. For example, after having a baby, many women experience hair shedding because estrogen levels drop. Then, when menopause hits, lower levels of estrogen and progesterone can lead to thinning hair.
Thyroid issues, like hypothyroidism and hyperthyroidism, also cause hair loss. Balancing your hormones and making sure you’re getting enough zinc, vitamin D, and magnesium keeps your hair healthy.
3. Nutrient Deficiencies
Hair is a non-essential tissue from your body’s survival standpoint, so when nutrient levels drop, your hair is one of the first places it shows. This makes low iron, magnesium, and zinc deficiencies some of the most common hidden drivers of hair loss.
Research shows a strong link between low zinc levels and hair loss, especially in conditions like telogen effluvium and alopecia areata. Adding a zinc supplement may help, but only if a deficiency is confirmed.
Other key nutrients include Vitamin D, biotin (B7), protein, and omega-3 fatty acids. These vitamins and minerals support hair structure, follicle growth, and circulation. That’s why proper blood testing is so important.
4. Telogen Effluvium (Stress-Induced Shedding)
High stress, illness, surgery, or rapid weight loss causes some of your hair to fall out more than usual. This results in diffuse thinning, often described as hair “coming out in handfuls.”
This condition is common, especially after major life events, and typically shows 2 to 3 months after the trigger. The good news is that it’s usually temporary and reversible with stress reduction and support from targeted vitamins for hair loss.
5. Autoimmune Hair Loss (Alopecia Areata)
In this condition, the immune system gets confused and starts attacking the hair follicles. This leads to bald spots, and in some cases, people may lose all their hair on their scalp or body.
While the exact cause isn’t fully understood, many people with this kind of hair loss often have low levels of certain nutrients, like zinc, vitamin D, and essential fatty acids. Some patients see improvement with zinc for hair growth as part of a broader immune-balancing strategy.
6. Scalp Conditions or Infections
Fungal infections like ringworm, seborrheic dermatitis, and ongoing scalp inflammation can hurt your hair follicles. These issues can get worse if your immune system or nutrient levels aren’t great.
Using shampoos or treatments that contain zinc can help. Zinc has antimicrobial and anti-inflammatory properties to create a healthier environment for your scalp.
7. Overstyling and Traction Alopecia
Tight hairstyles like braids, ponytails, or extensions, and frequent use of chemical or heat treatments put stress on the hair shaft and follicles. This damage leads to traction alopecia, a condition that’s often preventable and sometimes reversible.
8. Medications and Medical Treatments
Hair loss can be a side effect of chemotherapy, antidepressants, blood pressure medications, hormonal treatments, retinoids, and NSAIDs. If hair loss begins after starting a new medication, it’s best to consult with your doctor about potential alternatives.
9. Aging and Hormonal Decline
As we age, the hair growth cycle slows. Follicles may shrink or stop producing new hairs altogether.
A drop in estrogen during menopause triggers noticeable hair thinning for women. For men, age-related pattern baldness becomes more common. While aging is natural, consistent support with vitamins for hair growth can help preserve hair density.
10. Crash Diets and Disordered Eating
Hair needs calories, protein, and micronutrients to grow. If you're undereating, whether intentionally or not, your hair may suffer.
Deficiencies in iron, zinc, and protein are especially common in people following restrictive or low-calorie diets. In these cases, hair loss supplements can play a key role in replenishing what’s missing, but only if part of a broader nutritional strategy.
Preventing and Reversing Hair Loss Starts from Within
Hair loss can feel overwhelming and stressful, but the good news is that many causes are treatable once you identify them. Here are some ways to prevent and reverse hair loss:
1. Start with a Comprehensive Blood Test
Hair loss isn't just about what's happening on your scalp; it can be a sign of other issues. That's why the first thing you should do is get some blood work done.
Mito Health offers a detailed blood panel that looks at your ferritin levels, important nutrients like magnesium, zinc, and vitamin D, as well as inflammatory markers and hormones. This helps identify the real cause of your hair loss, whether it's a lack of certain nutrients, hormonal issues, or something else.
2. Supplement Strategically (Not Randomly)
If your labs show you're low in essential nutrients, targeted supplementation can make a real difference. But more isn’t always better.
The best supplements for hair growth aren’t trendy gummies—they’re evidence-based solutions tailored to your biology. That might mean a high-quality zinc supplement for follicle recovery, or iron support to bring up your ferritin levels.
3. Optimize Your Daily Habits
Hair health is a reflection of overall health. Alongside bloodwork and supplements, you need to eat enough protein and micronutrients daily. Manage stress with rest, movement, and sleep.
If possible, avoid harsh hair treatments and tight hairstyles. Lastly, support scalp health with gentle, nourishing care.
Hair Loss Has Many Causes—But One Smart Starting Point
Hair loss rarely comes down to just one thing. Stress, nutrient imbalances, hormone shifts, medical conditions, genetics, or a combination of them could be affecting your hair health.
At Mito Health, we start with advanced blood testing to uncover what’s going on—from low ferritin or magnesium to thyroid dysfunction or inflammation. Then, we build a plan that works for you—personalized supplements, smarter habits, and long-term support.