How To Thicken Hair: 12 Science-Backed Methods

While there are plenty of products promising thicker, fuller hair, not every solution has the science to back it up. Thankfully, there are evidence-backed ways to support hair density, reduce excessive shedding, and make your hair look and feel fuller over time. Some methods support the hair growth cycle, while others help reduce breakage or address nutritional factors that can contribute to shedding, so the key is often to understand why your hair is thinning in the first place.

Here are 12 science-backed ways to support thicker-looking, healthier hair over time.

1. Make Sure You’re Getting Enough Protein

Hair is primarily made of a protein called keratin, so adequate protein intake is important for normal hair growth.

Eating too few calories or not getting enough protein can contribute to noticeable hair shedding. This is particularly relevant after periods of restrictive dieting or rapid weight loss, when the body may prioritize essential functions over processes like hair production.

Instead of relying on a single food as a hair growth solution, focus on consistently eating a balanced diet that includes healthy protein sources such as eggs, fish, poultry, dairy, beans, lentils, tofu, nuts, and seeds.

2. Check for Nutritional Deficiencies

Iron, zinc, biotin , and other nutrients play roles in normal hair growth, so deficiencies in these areas can contribute to hair loss.

That said, this doesn’t mean everyone with thinning hair needs a high-dose hair vitamin. It’s best to find out whether you’re deficient before you start taking supplements.

If you're experiencing significant or persistent hair shedding , a healthcare professional can help determine whether bloodwork or other testing is appropriate.

3. Try Minoxidil

Minoxidil is a highly studied treatment for certain types of hair loss and is available in topical formulations without a prescription. Minoxidil can stimulate hair growth and help prevent further hair loss, although it generally takes several months to see results. Continued use is typically necessary to maintain the benefits.

Because minoxidil is a medication, it’s worth discussing with a dermatologist to determine whether it’s appropriate for your particular type of hair loss.

4. Identify and Manage Stress

Significant physical or emotional stress can affect the hair growth cycle and trigger a type of temporary shedding called telogen effluvium , in which more hairs than usual enter into the resting and shedding phase.

Managing stress won’t necessarily make your hair grow back overnight, but addressing ongoing stressors can support a healthier hair growth environment. Prioritizing adequate sleep, regular movement, balanced nutrition, and stress management practices can all play a part in a comprehensive hair wellness routine .

If you’re experiencing sudden or significant shedding after a stressful event, illness, or major dietary change, consider speaking with a healthcare professional.

5. Be Gentle With Your Hair

Sometimes the goal isn’t just to grow more hair, it’s to keep the hair you already have. Repeated pulling, aggressive brushing, tight hairstyles, and excessive tension can damage hair and, over time, contribute to hair loss . In an effort to preserve your existing hair, it’s best to brush or comb gently and avoid hairstyles that continuously pull or tug.

If your hair is already feeling fragile, try loosening tight hairstyles like ponytails and buns, using gentle detangling techniques, and minimizing unnecessary tension.

6. Cut Back on Excessive Heat and Chemical Damage

Frequent use of hot styling tools, bleaching, relaxing, and other chemical treatments can weaken the hair shaft and increase breakage.

Hair breakage isn’t the same thing as hair loss from the follicle, but it can make your hair look significantly thinner and prevent you from retaining length. Lowering the temperature on styling tools, using heat protection, spacing out chemical treatments, and giving your hair occasional breaks can help preserve the strands you have.

7. Take Care of Your Scalp

Your scalp is the environment in which your hair follicles grow, so scalp health matters. Regular cleansing can help remove excess oil, product buildup, and debris. If you’re experiencing persistent itching, flaking, inflammation, or other scalp symptoms, don’t simply pile on more hair products.

Conditions affecting the scalp can sometimes contribute to hair shedding and may require treatment. A dermatologist can help determine whether an underlying scalp condition is contributing to changes in your hair.

8. Consider Low-Level Light Therapy

Low-level light therapy (LLLT), sometimes called red-light therapy, is another option that has been studied for certain types of hair loss.

At-home light devices for hair loss , such as laser caps and combs, have shown promising results, although the evidence is still limited compared to other treatment options. If you’re considering an at-home device, look for one specifically designed and cleared for the type of hair loss you’re experiencing, and remember that consistency is important with light-based treatments.

9. Don’t Underestimate the Hair Growth Cycle

Hair doesn’t grow continuously at the same rate. Individual follicles move through different phases of growth, rest, and shedding. That means a temporary increase in shedding doesn’t necessarily mean you’re permanently losing hair or that improving the conditions around the follicle is guaranteed to produce visible thickness immediately.

Supporting healthy hair requires patience. Most evidence-backed approaches need to be used consistently for months rather than days or weeks before changes become noticeable.

10. Consider Hair Growth Peptides

Not every approach to thicker hair has to focus on vitamins or medications. Hair growth peptides offer another way to support the biology of the hair follicle. Peptides are short chains of amino acids that can play structural and signaling roles in the body, and certain peptide technologies have been studied for their potential role in hair health.

OMI takes a peptide-first approach with our patented IFP-131™ Hair Growth Peptides , which are designed to support keratin production and strengthen hair anchoring at the follicle. In a 90-day placebo-controlled study, participants saw up to 47% reduction in hair loss .

Different from simply taking a traditional hair vitamin and focusing exclusively on filling nutritional gaps, our peptide technology is designed to support the follicle’s internal structure and the hair’s connection to the scalp. For anyone interested in a drug-free addition to their hair routine, hair growth peptides are a method worth considering alongside other evidence-backed approaches.

11. Choose a Formula Based on Your Type of Hair Thinning

There can be several causes for hair thinning, which means there isn’t necessarily one universal solution, either. For example, hair shedding associated with rapid weight loss may involve different factors than shedding associated with prolonged stress. That’s why targeted formulas can be useful when they’re built around circumstances contributing to hair changes.

At OMI, we offer different peptide-powered formulas designed around specific hair wellness needs:

• Harmonize: For hormone-related hair thinning and shedding

• Nourish: For GLP-1-related hair thinning and shedding

• Revitalize: For stress-related hair thinning and shedding

12. Give Your Routine Time To Work

One of the most important and overlooked ways to support thicker-looking hair is to stay consistent. Hair grows slowly, and many evidence-backed treatments require months of regular use before results become noticeable. Constantly switching products makes it difficult to know what’s actually working.

Instead, choose an approach that makes sense for your hair concerns, follow the recommended usage, and give your routine enough time to produce measurable changes.

The Takeaway

Thicker-looking hair isn’t necessarily about finding one miracle product, but creating the right conditions for healthy hair growth while protecting the hair you already have.

The most science-backed strategies include getting enough protein and key nutrients, addressing deficiencies, managing stress, protecting hair from excessive tension and heat, caring for your scalp, and considering clinically studied treatments, such as minoxidil, low-level light therapy, and hair growth peptides like our IFP-131™ technology.

Whichever approach you choose, remember consistency matters.

Frequently Asked Questions

Can you actually make your hair thicker?

You can support thicker-looking hair by addressing shedding, protecting against breakage, and using evidence-backed treatments that support healthy hair growth.

What is the best way to thicken hair?

The best approach depends on the cause of thinning, but nutrition, scalp care, gentle hair practices, and clinically studied treatments can all support your hair thickening journey.

Do hair growth peptides help thicken hair?

Hair growth peptides are designed to support the biology of the hair follicle. OMI IFP-131™ Hair Growth Peptides support keratin production and hair anchoring.