Hair Loss and Thinning: Understanding the Hair Growth Cycle, Everyday Factors, and Nutrition

“I feel like I am losing more hair than usual when I shampoo.”

“My hair seems to have less volume than before.”

“My part or hairline is becoming more noticeable.”

Changes like these can be concerning for both men and women.

Seeing a large amount of shed hair can be especially worrying and may make you wonder, “Am I going to keep losing more hair?”

However, hair shedding itself is a natural part of the body’s normal processes.

Hair grows and sheds according to a repeating cycle known as the “hair growth cycle.” Even in a healthy scalp, some hairs naturally fall out every day as new hairs gradually replace them.

On the other hand, if shedding suddenly increases or individual hairs become noticeably thinner or shorter than before, there may be changes occurring beyond the normal replacement process.

Rather than immediately assuming that hair loss is caused by “poor nutrition” or “poor scalp circulation,” it is important to first understand how hair grows and why it naturally sheds.

In this article, we explain the basics of hair thinning and hair loss, common causes, everyday factors worth reviewing, and situations in which it may be appropriate to seek medical advice.

Later in the article, we will also look at the relationship between hair and nutrition, as well as propolis, royal jelly, and placenta, focusing on their general characteristics and the current state of hair-related research.

Why Does Hair Fall Out? Understanding the Hair Growth Cycle

Hair does not continue growing indefinitely once it appears.

Within the scalp are structures called hair follicles, where new hairs are produced. Each hair grows for a period of time, eventually sheds, and is then replaced by a new hair.

This repeating process is known as the hair growth cycle.

For scalp hair, the growth phase generally lasts around 2 to 6 years.

This is followed by a transition phase lasting several weeks and a resting phase lasting several months before the older hair is eventually shed.

Not all hairs enter the same phase at the same time. Each follicle follows its own cycle of growth and rest.

This staggered process helps maintain a relatively stable amount of hair under normal conditions.

Even Healthy People Naturally Shed Hair Every Day

Finding hair on your brush, pillow, or in the shower drain can make you wonder whether you are losing too much.

However, healthy people may naturally shed around 50 to 100 hairs per day.

This is part of the normal process in which hairs that have completed their growth cycle are replaced by new ones.

The amount you actually notice can also vary depending on hair length, how often you wash your hair, and how frequently you brush or comb it.

For this reason, there is usually no need to count every hair in the shower drain and assume that a specific number automatically means something is wrong.

How Quickly Does Hair Grow?

The rate of scalp hair growth varies from person to person, but on average, hair grows by around 1 cm per month.

This means changes in hair are not usually visible within just a few days or weeks.

Even after making changes to lifestyle habits or hair care, it takes time for newly growing hair itself to become visible.

Hair shedding triggered by a major physical change or significant stress may also appear with a delay, sometimes several months after the original event.

This time lag is one reason people may wonder, “Nothing unusual has happened recently, so why am I suddenly shedding more hair now?”

Increased Shedding and Progressive Hair Thinning Are Not the Same Thing

Another important point is that increased hair shedding and gradual thinning of individual hairs are not necessarily the same process.

For example, major physical changes, childbirth, rapid weight loss, or significant stress can cause a larger-than-usual number of hairs to enter the resting phase earlier than expected, resulting in increased shedding several months later.

This is one form of telogen effluvium. If the trigger was temporary, shedding may gradually settle over time.

By contrast, conditions such as AGA (androgenetic alopecia in men) are not defined only by sudden or heavy shedding.

As the growth phase becomes shorter, hairs can become progressively thinner and shorter, a process known as miniaturisation. Over time, this may make more of the scalp visible.

When looking at changes in your hair, it is therefore useful to consider not only how much hair is shedding, but also whether:

In other words, the pattern of shedding and thinning can be just as important as the number of hairs lost.

The Causes of Hair Thinning and Hair Loss Differ from Person to Person

Hair loss is sometimes explained simply as being caused by “poor scalp circulation” or “not getting enough nutrients.”

In reality, many different factors can be involved, including genetics, hormones, changes in physical health, immune-related conditions, nutritional status, illness, medications, and repeated physical stress on the hair.

For this reason, hair thinning and hair loss cannot be explained by a single food, supplement, or hair-care method.

In the next section, we will look more closely at the common causes of hair thinning and hair loss, including AGA, female pattern hair loss, telogen effluvium, and alopecia areata.

Common Causes of Hair Thinning and Hair Loss

Hair thinning and hair loss can look similar, but the way they develop can vary depending on the underlying cause.

Some conditions cause hair to become gradually thinner over time, while others lead to temporary increases in shedding following changes in physical health. Immune-related conditions can also cause hair loss.

Here are some of the more common causes to be aware of.

1. AGA (Androgenetic Alopecia in Men)

One of the most common causes of hair thinning in men is androgenetic alopecia, often referred to as AGA.

AGA typically begins after puberty and tends to progress gradually, often affecting the hairline and crown.

Genetic factors and male hormones both play an important role in this process.

DHT (dihydrotestosterone), which is produced from the male hormone testosterone, can act on hair follicles that are genetically sensitive to it. In these areas, the active growth phase of the hair cycle becomes shorter.

As a result, hairs may move into the next phase of the cycle before they have had enough time to grow long and thick. Over time, more hairs become finer and shorter, a process known as miniaturisation.

For this reason, AGA is not only about how many hairs are shedding. It is also useful to notice whether more hairs are becoming finer and shorter, or whether the hairline or crown is gradually changing.

2. Female Pattern Hair Loss

Hair thinning is not limited to men.

Women can also experience female pattern hair loss, in which hair density gradually decreases over time.

Rather than causing the same type of receding hairline commonly seen in male AGA, female pattern hair loss often presents as reduced overall volume around the top of the scalp or a part that gradually appears wider.

However, hair thinning in women can also be associated with other factors, including iron deficiency, thyroid disorders, rapid dieting, and certain medications.

For this reason, noticeable or persistent changes should not automatically be dismissed as “just ageing.”

3. Telogen Effluvium Following Physical or Emotional Changes

If hair shedding suddenly increases, a condition known as telogen effluvium may sometimes be involved.

Telogen effluvium occurs when a larger-than-usual number of hairs shift from the active growth phase into the resting phase following a significant physical or emotional change. These hairs may then shed later in greater numbers.

Possible triggers include:

With telogen effluvium, increased shedding may not begin until several months after the triggering event.

If the trigger was temporary, the shedding may gradually settle over time.

However, if shedding continues for a long period or is accompanied by other changes in your health, it may be worth checking whether another factor is involved.

4. Alopecia Areata

Hair loss that appears in round or oval patches may be associated with alopecia areata.

Although it is sometimes described simply as being caused by severe stress, alopecia areata is currently understood to be an autoimmune condition in which growing hair follicles are targeted by the immune system.

This immune response can interfere with normal hair growth.

The condition may affect a single patch, several areas, or a larger portion of the scalp.

5. Nutritional Deficiency and Extreme Dieting

Hair is made primarily from a protein called keratin.

Maintaining hair and other tissues throughout the body requires adequate energy intake and a variety of nutrients.

Extreme dieting or a major reduction in food intake can result in nutritional deficiencies that may contribute to increased hair shedding.

In some cases, deficiencies in protein, iron, zinc, and other nutrients may be associated with hair loss.

However, “a deficiency may affect hair” does not mean that “taking more will make more hair grow.”

The basic approach is to focus on the overall balance of your diet rather than consuming large amounts of a single nutrient.

6. Thyroid Disorders and Other Health Conditions

Hair loss is not always caused by something happening only in the scalp.

For example, thyroid disorders can sometimes be associated with changes in hair texture or increased shedding.

Iron deficiency, certain health conditions, and some medications may also affect hair growth or shedding.

It is especially worth paying attention if you notice:

In these situations, it is important not to assume that the issue is limited to the hair or scalp alone.

7. Hairstyles and Everyday Hair-Care Stress

Everyday hairstyles and hair-care practices can also place repeated stress on the hair shaft or hair follicles.

For example, regularly wearing very tight ponytails or buns can repeatedly pull on the follicles.

Hair loss caused by this type of repeated tension is known as traction alopecia.

If strong pulling continues for a long time, the hair may become less likely to fully recover, so reducing the tension early is important.

Other practices that can contribute to hair damage include:

These habits can damage the hair shaft itself and increase breakage and split ends.

Sometimes hair may appear to have less volume not because it is shedding from the follicle, but because more strands are breaking along the shaft.

The Same “Hair Loss” Can Require Very Different Approaches

As we have seen, hair thinning and hair loss can have many different causes.

AGA may involve genetic and hormonal factors, alopecia areata involves the immune system, telogen effluvium can follow major changes in physical or emotional health, and nutritional status, illness, medication, or repeated physical stress on the hair may also play a role.

So what can you realistically review in everyday life?

In the next section, we will look at diet, sleep, stress, and hair-care habits that may be worth reviewing when you are concerned about hair thinning or hair loss.

Everyday Factors to Review When You Are Concerned About Hair Loss

When hair thinning or shedding becomes noticeable, it is natural to wonder whether changing your lifestyle might help.

Diet, sleep, and everyday hair care are all important for maintaining general health and keeping the hair and scalp in good condition.

However, conditions such as AGA (androgenetic alopecia in men), female pattern hair loss, and alopecia areata cannot be prevented or resolved through lifestyle changes alone.

Rather than thinking, “If I do this, my hair will grow back,” it is more appropriate to focus on getting adequate nutrition and rest while reducing unnecessary stress on the hair and scalp.

Focus on a Balanced Diet Rather Than a Single “Hair Food”

Maintaining hair and other tissues throughout the body requires adequate energy and a variety of nutrients.

When people become concerned about hair loss, they may start looking for a particular food that is “good for hair.” However, hair health is not determined by any single food.

A better approach is to combine foods such as meat, fish, eggs, soy products, vegetables, fruit, and grains, and to focus on the overall balance of your diet.

Rapid weight-loss diets can reduce both energy and nutrient intake and may be followed by increased hair shedding later on.

If you are trying to lose weight, it is better to avoid extreme restriction and take your overall health into account.

More Supplements Do Not Necessarily Mean Better Results

When hair loss is a concern, it can be tempting to add supplements containing iron, zinc, vitamins, or other nutrients.

If a specific nutrient deficiency is actually present, addressing that deficiency may be necessary.

However, taking larger amounts of nutrients that you are not deficient in does not mean they will provide additional benefits for your hair.

Some vitamins and minerals can also cause problems when consumed in excessive amounts.

Make Time for Adequate Sleep and Rest

You may come across claims suggesting that you must go to bed by a particular time “for your hair.”

However, there is no single fixed bedtime that has been established as necessary to prevent hair loss.

Rather than looking for a special sleep routine specifically for hair, the priority is to get enough sleep for your own needs and allow your body adequate time to rest.

If you are regularly sleep deprived or constantly fatigued, it may be useful to review your overall daily routine.

If Stress Is Persistent, Avoid Pushing Yourself Too Hard

Having stress does not automatically mean that you will develop hair loss.

However, significant physical or emotional stress can sometimes be followed by telogen effluvium several months later.

Possible triggers vary widely and may include work, relationships, major life changes, illness, or surgery.

It may not be realistic to remove all stress from everyday life, but making time for adequate rest, light physical activity, and things you enjoy can help create regular opportunities for both physical and mental recovery.

If you are also experiencing persistent insomnia, loss of appetite, or a significant low mood, consider seeking medical advice rather than focusing only on your hair.

Wash the Scalp Gently Rather Than Scrubbing Hard

When shedding increases, some people feel they need to remove as much scalp oil as possible by washing more aggressively.

However, there is generally no need to scrub the scalp excessively or repeatedly use very strong cleansing products.

When shampooing, avoid scratching with your nails and focus on gently removing dirt, excess oil, sweat, and styling products from the scalp.

How often you need to wash your hair can vary depending on hair type, scalp oiliness, how much you sweat, and your lifestyle, so there is no single washing frequency that suits everyone.

Handle Wet or Damaged Hair Gently

Wet hair is more vulnerable to damage from friction and pulling.

Rubbing vigorously with a towel or forcing a brush through tangled wet hair can contribute to breakage.

After washing, gently press the hair with a towel to remove excess water and avoid pulling strongly while detangling.

Using a conditioner where appropriate may also help reduce friction and tangling.

Avoid Prolonged Exposure to Excessive Heat

Repeated heat from hair dryers, straighteners, and curling irons can damage the hair shaft.

When using a hair dryer, avoid holding very hot air on the same area for a long time and keep the dryer at a reasonable distance from the hair.

Hair straighteners and curling irons should also be used at an appropriate temperature and not more frequently than necessary.

If colouring, perming, or chemical straightening has already damaged the hair, allowing more time between treatments may help reduce additional stress on the hair shaft.

Avoid Keeping the Hair Under Strong Tension for Long Periods

Tight ponytails, buns, braids, or other hairstyles that repeatedly pull strongly on the hair can place ongoing stress on the follicles.

If you regularly tie your hair back, consider:

If you notice scalp discomfort or increasing breakage around the hairline, it may be a good time to adjust your hairstyle.

Do Not Rely on Scalp Massage as a Hair-Loss Treatment

Some people enjoy scalp massage as a way to relax or unwind.

However, scalp massage alone does not treat conditions such as AGA.

More pressure is not necessarily better. If you massage your scalp, avoid scratching with your nails or rubbing aggressively, and use only gentle pressure that does not irritate the skin.

Maintain Healthy Basics and Pay Attention to Ongoing Changes

When hair thinning or shedding becomes concerning, there is no need to look for a single special food or shampoo as the answer.

These habits are not methods for preventing every type of hair-loss condition.

However, they are useful as part of maintaining general health and reducing avoidable stress on the hair and scalp.

If hair shedding continues despite reviewing your everyday habits, or if thinning is gradually progressing, it is also important not to keep searching for the cause through diet and hair care alone.

In the next section, we will look at signs that may warrant medical advice and some of the treatment options used for conditions such as AGA.

When to Consider Medical Advice and Treatment Options

If you notice increased shedding or gradual thinning, you may wonder whether the change is significant enough to see a doctor.

Some temporary changes in shedding can occur after illness, stress, or other physical changes and may settle over time.

However, conditions such as AGA, female pattern hair loss, alopecia areata, and certain underlying health problems may require medical assessment or treatment.

If the changes are clearly different from your usual pattern or continue over time, it may be worth consulting a dermatologist or another qualified healthcare professional.

Changes That May Be Worth Discussing With a Healthcare Professional

The number of hairs you shed is not the only factor that matters.

Consider seeking medical advice if you notice changes such as:

In particular, sudden patchy hair loss, significant scalp inflammation, or a rapid change in shedding is a reason not to rely on self-care alone for an extended period.

How Is the Cause of Hair Loss Assessed?

When you seek medical advice for hair thinning or hair loss, the assessment usually involves more than simply looking at the scalp.

A healthcare professional may ask about factors such as:

These details can help provide clues about the possible cause.

Depending on the symptoms, blood tests may also be considered to check for factors such as iron deficiency or thyroid-related conditions.

Common Treatment Options for AGA in Men

AGA is a progressive form of hair loss influenced by genetic factors and the effects of male hormones.

Clinical guidelines from the Japanese Dermatological Association recommend topical minoxidil as a treatment option for male androgenetic alopecia.

For men, oral finasteride and dutasteride are also recommended treatment options.

These medicines work in different ways and may not be suitable for everyone. They can also have side effects.

If you are considering medication for hair loss, seek advice from a doctor, pharmacist, or other appropriately qualified healthcare professional rather than choosing treatment solely on your own.

Treatment Options for Female Pattern Hair Loss

Hair thinning in women should not automatically be attributed to ageing.

For female pattern hair loss, Japanese dermatology guidelines recommend topical minoxidil as a treatment option.

By contrast, finasteride and dutasteride, which are used in men with AGA, are not recommended for female pattern hair loss in these guidelines.

Because hair thinning in women can also be associated with other causes, persistent or significant changes are worth assessing before assuming that female pattern hair loss is the only explanation.

Alopecia Areata Requires a Different Approach From AGA

Alopecia areata is a different condition from androgenetic alopecia.

It is currently understood to be an autoimmune condition in which growing hair follicles are targeted by the immune system.

The treatment approach can vary depending on factors such as age, the extent of hair loss, and how the condition is progressing.

If you develop round or oval patches of hair loss, consider consulting a dermatologist rather than trying to manage the condition with general hair care or health supplements alone.

With Telogen Effluvium, Look Back at Possible Triggers

Telogen effluvium may occur several months after a major illness, high fever, surgery, childbirth, rapid weight loss, or significant emotional or physical stress.

If the original trigger was temporary, the increased shedding may gradually settle with time.

However, if shedding continues for an extended period, medical assessment may help determine whether another factor is involved.

If you suspect that a medication may be contributing to hair loss, do not stop taking prescribed medication on your own.

Discuss your concerns with the healthcare professional who prescribed the medicine or with a pharmacist.

Hair-Growth Medicines, Hair-Care Products, and Health Supplements Have Different Roles

When researching hair loss, you may come across terms such as “hair growth,” “hair care,” and “hair health.” These do not all refer to the same type of product or purpose.

Medicines intended to promote hair growth, products designed to help maintain the condition of the hair or scalp, and health supplements used to support everyday nutrition all have different roles.

Health supplements are not medicines intended to treat conditions such as AGA or alopecia areata.

So far, we have looked at how hair grows and sheds, common causes of thinning and hair loss, everyday factors worth reviewing, and situations in which medical advice may be appropriate.

In the final section, we will look at the relationship between hair and nutrition, and how to approach health supplements in a balanced and realistic way.

We will also look at propolis, royal jelly, and placenta—not as products intended to treat hair loss, but from the perspective of their general characteristics and the types of hair-related research that have been conducted.

Hair, Nutrition, and a Balanced Approach to Health Supplements

Hair is part of the body, and supporting general health begins with everyday nutrition.

Rather than focusing on one particular food or nutrient, it is better to aim for a balanced diet that includes protein-containing foods, vegetables, fruit, grains, and other varied sources of nutrition.

Health supplements can be one option for complementing your usual diet or supporting your everyday health routine.

They are not medicines intended to treat conditions such as AGA or alopecia areata.

At the same time, some natural substances that are also used in health products have been studied in basic or clinical research related to hair.

Here, we look at propolis, royal jelly, and placenta from the perspective of their general characteristics and the current stage of hair-related research.

Propolis | A Natural Bee-Derived Substance Containing Plant Compounds

Propolis is a resinous material produced by bees from substances collected from plant buds, bark, and other botanical sources, together with beeswax and other components.

Bees use propolis to help seal gaps and maintain the environment within the hive.

Propolis contains a variety of plant-derived compounds, including flavonoids and phenolic substances.

However, its composition is not fixed.

The compounds present can vary depending on the source plants, geographic region, season, and bee species.

For this reason, it is more appropriate to think of propolis as a diverse natural substance rather than assuming that all propolis products contain exactly the same components.

Current Research on Propolis and Hair

Hair-related research involving propolis has included basic studies using animals and cells.

For example, studies using Brazilian propolis have examined mouse skin, hair follicles, and cells involved in hair formation.

These studies may provide useful clues for understanding how compounds found in propolis interact with biological processes related to hair follicles.

However, results from animal studies cannot automatically be applied to humans.

It is also important to distinguish between research involving topical application to the skin and the use of propolis as a food or supplement taken orally.

Further research, particularly well-designed studies in humans, is needed before clear conclusions can be drawn about propolis and hair.

Royal Jelly | A Distinctive Nutritional Substance Produced by Worker Bees

Royal jelly is a pale, creamy substance secreted by worker bees.

Queen bees continue to consume royal jelly as a major source of nutrition throughout adulthood.

Royal jelly contains proteins, carbohydrates, fats, vitamins, minerals, and other naturally occurring compounds.

One of its characteristic fatty acids is 10-HDA (10-hydroxy-2-decenoic acid).

Because of its distinctive composition, royal jelly has been studied in a variety of health-related fields.

Current Research on Royal Jelly and Hair

Royal jelly has also been studied in relation to hair.

In 2026, a randomised, double-blind, placebo-controlled trial involving 70 adults who felt that their hair was thinning evaluated a topical formulation containing royal jelly extract over a 12-week period.

The study assessed several measures, including hair density, hair elongation, and hair quality, and the results varied across the different outcomes.

For hair density, no clear statistically significant difference was identified between the royal jelly group and the placebo group.

The researchers noted that larger clinical studies would be needed to confirm the findings.

It is also important to note that the study used a royal-jelly-containing formulation applied directly to the scalp.

It was not a study of royal jelly taken orally as a health supplement.

Research on royal jelly and hair remains limited, and further investigation is needed.

Placenta | A Material Studied in a Variety of Research Fields

The word “placenta” refers to the organ that develops during pregnancy.

In health supplements and cosmetic products, the placenta itself is not generally used directly. Instead, processed extracts or other placenta-derived materials may be used.

Sources can include animals such as pigs, horses, and sheep, and the composition can vary depending on the species and manufacturing method.

Placenta-derived extracts may contain amino acids, peptides, and other compounds, and they have been studied in a range of health and beauty-related fields.

Current Research on Placenta and Hair

Hair-related research involving placenta includes cell-based studies, animal studies, and some human research.

In 2020, a randomised, double-blind trial involving 90 women with female pattern hair loss compared a topical lotion containing bovine placenta with 2% topical minoxidil.

However, the study had limitations, including its sample size and study duration, and the product used was specifically a topical formulation containing bovine-derived placenta.

It was not a study of placenta taken orally as a health supplement.

It is also important to remember that products described as “placenta” can differ in animal source, manufacturing process, and method of use.

When reading research on placenta, it is therefore important to check which source material was used, how it was administered, and who participated in the study.

“Studied” Does Not Mean “Proven as a Health Supplement”

Propolis, royal jelly, and placenta have all been investigated in research related to hair.

However, the type and stage of evidence differ considerably between them.

In health and beauty research, cell studies, animal studies, and human studies do not provide the same level or type of evidence.

Even in human studies, results from a product applied to the scalp cannot automatically be treated as evidence for the same ingredient when taken orally.

Rather than focusing only on the phrase “there is research on this ingredient,” it is important to ask what was studied, who was studied, and how the material was used.

What to Keep in Mind When Choosing Health Supplements

When hair thinning or hair loss becomes a concern, it is understandable to become interested in foods or ingredients that are promoted as being “good for hair.”

However, health supplements should not be chosen based only on hair-related claims or research.

It is more useful to consider whether a product fits your overall diet, health status, and everyday routine.

Natural ingredients are not automatically suitable for everyone.

Bee-derived products such as propolis and royal jelly may also require additional caution for people with certain allergies or sensitivities.

If you are taking medication, receiving treatment for a health condition, pregnant, or breastfeeding, consider speaking with a doctor, pharmacist, or other qualified healthcare professional before using health supplements.

If you use several supplements at the same time, check the ingredient lists and recommended daily amounts so that you are not unknowingly taking excessive or duplicate amounts of the same nutrients or compounds.

Summary | Start by Understanding How Your Hair Is Changing

Hair naturally grows and sheds according to the hair growth cycle, so losing some hair every day is a normal biological process.

However, a sudden increase in shedding, increasingly fine or short hairs, or visible changes around the hairline, crown, or part may indicate that something different is happening.

AGA, female pattern hair loss, telogen effluvium, alopecia areata, nutritional status, illness, medications, and repeated physical stress on the hair can all contribute to different patterns of hair thinning or hair loss.

Propolis, royal jelly, and placenta have all been studied in relation to hair, but the research conditions and methods of use vary considerably. These findings should not be treated as evidence that the same effects occur when the ingredients are taken orally as health supplements.

If you are concerned about hair thinning or hair loss, avoid looking for the answer in a single ingredient alone. Start by paying attention to how your own hair has changed.

Support your general health through a balanced diet, adequate sleep and rest, and gentle hair care, and consider consulting a dermatologist or another qualified healthcare professional if noticeable changes continue.