10 Scientifically Proven Ways to Grow Thicker Hair Naturally

Reading time: 15 min.

Medically reviewed by
Dr. Michael May (FRCS) — Updated on June 16, 2026

In today’s world of marketing misinformation, it can be challenging to find scientifically proven ways to grow thicker hair naturally. More than 85% of men and 55% of women experience hair loss or hair thinning during their lifetime [1][2], and an entire industry has emerged to offer them solutions. There are many herbal products out there that guarantee hair growth results but can provide no independent clinical trials to support their claims.

However, you will be glad to learn that there are some natural remedies for combating hair loss and thickening your hair with demonstrated efficiency. Some of these are essential oils for hair growth, others are therapies such as scalp massage for hair growth or lifestyle changes that can give you stronger, healthier strands. What they have in common is that they can make your hair thicker without any synthetic treatment.

Keep reading this article to discover all you need to know about naturally increasing your hair density and thickness, such as:

The most common reasons your hair may be thinning
The best scientifically proven natural remedies for thicker hair
How to thicken your hair naturally as quickly as possible
What to do when natural remedies fail

Table of Contents

Why is my hair becoming thinner?
The best scientifically proven ways to grow thicker hair naturally
Can thin hair become thick again in women?
How to thicken your hair naturally in a month
What to do if natural hair thickening remedies are not enough

Why is my hair becoming thinner?

Some hair loss is normal in the shower or when brushing your hair. In fact, even people with perfectly healthy locks can expect to shed 100-150 strands each day as part of their natural hair growth cycle. But if your hair is becoming so thin you can see your scalp, there may be an underlying problem. Here are some of the most common causes why that may happen:

Ageing – as you grow older, your hair follicles start to get smaller and produce finer hair, due to reduced follicle blood supply and hormonal changes that come with age.
A type of alopecia – androgenetic alopecia is the most common cause of hair thinning in density and diameter alike. However, other conditions, such as telogen effluvium, traction alopecia or alopecia areata can lead to sparser hair as well.
Common scalp problems – yeast infections on the scalp, such as seborrheic dermatitis or autoimmune conditions, such as scalp psoriasis, can cause inflammation that can lead to hair shedding. They can also cause an itchy scalp that can make you scratch vigorously, facilitating hair breakage.
Hormonal imbalances – as you advance in age, your hormonal balance naturally shifts, affecting your hair, which is sensitive to male and female hormone fluctuations. Thus, it is common to see women trying to reverse hair thinning after menopause. Moreover, thyroid disorders can cause hair loss as well, as can other endocrine conditions, such as polycystic ovary syndrome (PCOS).

The best scientifically proven ways to grow thicker hair naturally

Not all natural remedies are created equal; some can possess far greater qualities than others when it comes to stimulating your hair to grow denser and thicker. Here, you’ll learn how to thicken your hair naturally and discover the best treatment options, according to science.

1. Rosemary oil

Using rosemary oil for hair growth can be as effective as topical Minoxidil, provided that you apply it consistently. It can achieve good results in treating androgenetic alopecia, and it can also help decrease the symptoms of alopecia areata. It’s one of the best scientifically proven ways to grow thicker hair.

A clinical trial [3] conducted on 100 patients with male pattern baldness involved treating half of them with Minoxidil 2% and the other half with rosemary oil for 6 months. Results revealed similar effectiveness for both medications. They also indicated that 100% of the men in the rosemary oil group reported some hair loss improvement after 6 months of use and 38% experienced a mild increase in hair growth (compared to only 24% in the Minoxidil group – however Minoxidil 5% is usually recommended for men).

Another study of 84 patients with alopecia areata showed that 44% of patients treated with rosemary oil showed improvement in hair growth after 7 months, compared to only 15% in the placebo group [4].

The reason the best-diluted rosemary oil blends for hair growth can achieve such good results is twofold. Firstly, some of this plant’s components are natural DHT blockers, which can reduce the symptoms of male and female pattern baldness.

On the other hand, it contains substances such as camphor that can relax the blood vessels in your scalp, increasing blood flow to your hair follicles [3]. It also contains carnosol and carnosic acid, which have antioxidant properties that reduce oxidative stress [5].

2. Pumpkin seed oil

There is scientific evidence that pumpkin seed oil for hair growth can promote the development of denser, thicker hair in both men and women with androgenetic alopecia.

One clinical trial performed on 76 men with male pattern baldness revealed a 40% increase in their hair count after 6 months of taking capsules that contained pumpkin seed oil [6]

Another study performed on 30 women with female pattern baldness treated with topical pumpkin seed oil showed a significant decrease in hair miniaturisation and increased strand regrowth after 3 months of treatment [7].

3. Peppermint oil

It is true that peppermint oil for hair growth has so far been insufficiently tested in humans. However, animal studies show excellent results in promoting increased hair density. Research conducted on mice reveals that regularly applying this oil increased their hair growth rate by 92% in a single month, with no notable side effects [8].

This result was comparable to that of Minoxidil, possibly due to a similar mechanism of action. The menthol in this oil’s composition acts as a vasodilator when applied topically, allowing more oxygen and nutrients to reach your hair follicles.

Moreover, since peppermint oil contains menthol, it has also been found to reduce inflammation and itchiness caused by dandruff and seborrheic dermatitis. This can reduce unnecessary hair breakage caused by scratching and increase overall scalp comfort [9].

4. Black seed oil

While several hair growth oils are effective against androgenetic alopecia, black seed oil is among the very few natural remedies that can improve telogen effluvium.

A study performed on 20 women with this condition treated for 3 months with topical black seed oil for hair growth showed significant hair density and thickness improvement in 70% of patients [10]. It is theorised that this effect is due to one of its main components, thymoquinone, which possesses anti-inflammatory properties [10].

Furthermore, black seed oil is proven to regulate your hair growth cycle, preventing excess shedding and allowing your follicles to remain in the growth phase for longer [11].

This natural remedy has also been found to possess antifungal and antibacterial properties that can relieve the symptoms of scalp problems such as dandruff, seborrheic dermatitis, acne and scalp folliculitis [12].

5. Caffeine shampoo

We are all grateful to caffeine for waking us up in the morning. However, it may help with your thinning hair as well. Several studies have demonstrated that shampoos that contain caffeine, such as Alpecin can work for improving your hair growth in androgenetic alopecia [13][14].

Research revealed that after 6 months of use, patient hair shafts were stronger and thicker and that topical application of a caffeine solution could curb hair loss comparably to Minoxidil (however, it is debatable if a caffeine shampoo for hair loss would have the same effect) [15]. Moreover, a study performed on women with female pattern hair loss revealed that they presented less hair shedding in a hair pull test [16].

It is theorised that when applied topically in lotions or shampoos, caffeine can prevent hair loss by countering the negative impact of dihydrotestosterone (DHT) on your follicles. It can also help your scalp and hair retain moisture and has antioxidant and growth-regulating properties [14]. You may also benefit from the effects of caffeine on hair growth by applying cold coffee directly to your scalp.

6. Daily scalp massage

A head massage is not only relaxing, but it can also make your strands grow thicker. 15-20 minutes of scalp massage for hair growth per day can help relieve stress and increase blood flow to your hair follicles.

Studies performed on men with healthy hair [17] and those focusing on patients with male pattern baldness [18] showed significant improvement in hair thickness within 6 months of daily scalp massages. This is believed to happen because stimulating scalp circulation increases the amount of oxygen and nutrients received by follicles. However, it also appears that stretching your skin can activate certain genes that play an important role in hair production [17].

Moreover, regular scalp massages can help lower your stress levels, which makes you less exposed to unnecessary hair shedding caused by telogen effluvium [19]. You can easily massage your scalp with your fingers or use one of the best scalp massagers for hair growth.

7. A healthy hair diet

A balanced diet for healthy hair, with all major food types, is crucial in maintaining full, thick strands. That is because your hair needs all kinds of nutrients, such as protein, minerals and vitamins, for hair growth [20]. The reason why sudden weight loss also causes hair loss in many people is that it deprives their bodies of the hair-growth foods they need [21].

Certain vitamin deficiencies can cause hair loss and there is no guarantee that supplementing will make it grow back to the way it used to be. So if you want to have thick hair, you need to make sure you are getting enough nutrients, such as [20][21][22]:

Vitamin A (found in fish, eggs, oranges, yellow vegetables (e.g. bell peppers), carrots, dark leafy greens (e.g. spinach, broccoli). Be mindful that excessive vitamin A can cause hair loss.
Vitamin B (biotin for hair loss), found in dairy (milk, cheese), eggs, spinach, salmon, seafood, chicken, beef
Vitamin C for hair, found in citrus fruit (lemons, oranges, grapefruit), berries, kiwi, broccoli, potatoes
Vitamin D for hair, found in citrus fruit (lemons, oranges, grapefruit), berries, kiwi, broccoli, potatoes
Vitamin E for hair, found in sunflower seeds, almonds, spinach and avocados
Iron, found in liver, red meat, spinach, pumpkin seeds, poultry, quinoa, shellfish
Zinc, found in red meat, poultry, shellfish, beans, lentils, nuts, seeds, eggs, whole grain bread, dairy
Selenium, found in brazil nuts, tuna, eggs, brown rice
Protein, found in eggs, poultry, pork, veal, shellfish, dairy, oats, broccoli, almonds

Moreover, making sure that you drink enough water and avoiding frequent alcohol consumption can prevent dehydration, which can lead to dry, brittle hair that breaks off easily.

8. Smoking cessation

Everyone has heard that cigarettes can have serious detrimental effects on your health. However, fewer people are aware that smoking can cause hair loss as well. However, it is true. A meta-analysis performed on 16 studies [23] revealed that this habit can:

Reduce blood flow to your hair follicles
Create permanent microinflammation in your system (including your scalp)
Increase oxidative stress which can damage your hair
Increase your levels of testosterone which can contribute to hair shedding

These findings were confirmed by a study with 3427 male participants, which revealed a 15% higher level of testosterone in smokers than non-smokers [24].

Research conducted on 1000 men also showed a significantly higher rate of male pattern baldness among smokers, as well as indications that this habit can accelerate the progression of androgenetic alopecia [25].

9. Reducing your stress levels

Excessive stress can wreak havoc on many of the natural processes in your body and can severely impact your mental health and well-being. However, too much stress and anxiety can also cause hair loss. That is because it can disrupt your natural hair growth cycle, triggering telogen effluvium [26]. The good news is that there are stress-relieving strategies to reduce hair loss that you can use, such as:

Spending time in nature
Having a regular exercise routine
Getting enough rest
Engaging in meditation and mindfulness
Refusing new commitments when overwhelmed
Practising a creative hobby
Spending quality time with friends and family
Enlisting the help of a therapist and/or spiritual advisor

10. Good hair styling practices

Keeping your hair full and thick often involves providing adequate care and protecting it from practices that can break or damage your strands. The best things you can do to help your hair are to handle it gently, keep it well-moisturised and wash it frequently.

Don’t worry; it’s a hair loss treatment myth that washing your hair every day will make it fall out. In fact, research shows that cleaning your strands and scalp daily reduces hair loss, dandruff, seborrheic dermatitis, and greasy hair [27].

When it comes to things you should avoid that can potentially damage your strands, here are the most common mistakes:

Heat-styling too frequently – hair straighteners, curling irons and even hot blow drying can dry out your strands and it can be difficult to fix heat-damaged hair. If you don’t feel comfortable skipping your daily heat styling, try using a heat protector, such as argan oil or shea butter.
Excessive use of harsh chemicals – overuse of bleach or hair dye can cause hair loss, due to chemicals such as ammonia or hydrogen peroxide which can seep into your strands and damage their structure.
Wearing overly tight hairstyles – while they may look stylish, braids, top knots, and ponytails can cause hair loss if worn for too long. That is because they can trigger a condition called traction alopecia. Heavy extensions can cause hair loss as well by the same principle.
Overexposure to the sun – contrary to what some people think, excessive sunlight is not good for your hair. That is because it can dry out your strands and burn your scalp, leading to summer hair loss.

11. Eggs

To get fuller, thicker hair, you may need to break some eggs. Literally. Take a couple, whip them up, apply them to your moist hair and leave them on for about half an hour. Then wash your hair normally, with warm water and shampoo.

A 2018 study investigated the use of water-soluble peptides from egg yolk as a hair growth treatment. These peptides were tested on human hair follicle cells in vitro, and on living mice. Findings suggested the peptides may improve hair growth in female pattern hair loss [28].

While promising, research on this topic is very limited. Further studies are required to confirm whether applying egg directly to your hair is helpful for growth. Learn more about eggs for hair growth.

12. Onion juice

Onion juice may help you get thicker, fuller hair. Some studies have shown that onion juice may help improve hair growth in people affected by alopecia areata [29-30], but research is limited and further studies are needed to confirm these findings.

To try it for yourself, take 2 cups of freshly diced onion, squeeze them using a juicer or press and add the resulting fluid to a natural hair shampoo.

Use it to wash your hair and scalp, leaving it on for about 5 minutes before rinsing. Should there be any smell left over, just use a bit of lemon juice while rinsing and your hair should smell fresh in no time.

Onion oil for hair may provide a less intense alternative than raw onion juice. However, the preparation of onion oil may change the overall effectiveness of this extract.

13. Coconut oil

The smell of coconut usually evokes white beaches and delicious cocktails, but this amazing plant has many uses. Coconut oil was named “the holy grail of haircare” by Harper’s Bazaar because it is brimming with a fatty acid called lauric acid, which moisturises your scalp and promotes hair growth.

Research suggests that coconut oil can reduce oxidative stress, prevent hair protein loss and may possess antimicrobial and anti-inflammatory properties [31-33]. The high content of fatty acids in coconut oil can coat your hair, nourishing it and sealing moisture inside [31].

If you want to grow thicker, fuller hair naturally, heat up a couple of tablespoons of coconut oil in the evening, apply it to your hair, then wrap your head in a bath towel and let it sit until morning. After you wake up, wash your hair normally with water and shampoo.

Can thin hair become thick again in women?

The likelihood of a woman’s hair thickening again after thinning depends on what caused this problem in the first place. If it has been brought on by a type of alopecia, the right hair growth treatment for her specific condition may help. If a hormonal imbalance, a systemic illness, or nutritional deficiency is at fault, treating the underlying cause will often solve the thinning as well.

However, if she is experiencing normal age-related thinning, hair growth and thickening products such as hair thickening shampoo may somewhat help, but she is unlikely to regain the same hair thickness and density she had in her youth. Similarly, if her strands are genetically on the fine side, short of hair thickening sprays, there is not much that can make a significant difference.

How to thicken your hair naturally in a month

Hair growth takes time, as your strands have their natural cycle to follow. While some natural remedies can stimulate your follicles for thicker growth, this is unlikely to happen overnight.

Even hair loss medication and therapies can take months to produce significant results. However, if you really need to know how to thicken your hair naturally and you only have up to a month to do so, here are some things you can try:

Drink plenty of water and eat a diet rich in vitamins, antioxidants, and other essential nutrients
Reduce alcohol and cigarette consumption as much as possible
Wash your hair daily with a natural shampoo for thinning hair
Keep your hair well-moisturised and conditioned at all times
Avoid bleaching, dyeing or heat-styling your hair during this time
Engage in exercise and relaxing activities to reduce stress
Try natural hair masks with ingredients like eggs, onion juice and coconut oil

The effect of these actions can differ from one person to another, and there is no guarantee that they will thicken your hair in the required amount of time. But they can improve your strand health, as well as your overall well-being, so there is no harm in trying them.

Should you fail to increase your hair thickness in a month, remember that you can always hide your thinning hair with one of the best hairstyles for men with thin hair (or, respectively, the best hair loss styles for women who are thinning at the crown). You can even try the best bangs for a thinning fringe if you are experiencing frontal balding.

What to do if natural hair thickening remedies are not enough

If you have noticed the first signs of hair thinning and balding that do not improve with any natural remedy, it is time to book a consultation with a trichologist. You may be developing a type of alopecia that can progress if improperly treated. This usually happens with male or female pattern baldness, but other conditions, such as alopecia areata or chronic telogen effluvium, may also require treatment.

A hair doctor will perform specific trichology tests (e.g. a dermoscopy or blood tests for hair loss) and discover the exact reason why your hair is falling out. Once diagnosed, they can provide you with the best hair loss treatment for women (or, by case, the best hair loss treatments for men). While they will consider your preference for natural remedies, they will also recommend any necessary medication.

Or, if you are a good candidate, they may even suggest a hair transplant. While it is not a natural solution, hair restoration surgery is a once-in-a-lifetime event, as hair transplants are permanent. It is also safe, painless and requires no hospitalisation. This means that by getting a medical procedure once, you can still enjoy the results 10 years after your hair transplant or even longer.