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We know how frustrating it can be to experience hair loss or hair thinning, especially when you can't pinpoint the cause. But luckily, there are tons of different products out there to target and treat these issues. But with so many products out there with claims that seem too good to be true, how do we know which actually work? To find out, we spoke with board-certified dermatologist Dr. Sheila Farhang to find out what causes hair thinning or hair loss and which products are best for re-growing hair.

What Causes Hair Thinning and Hair Loss?

To start, let's address one important question: is there a difference between hair loss and hair thinning. According to Dr. Farhang, "hair thinning is technically a decrease in the actual strand width causing breakage" while hair loss refers to "decrease in density of hair on the scalp."

Hair loss and hair thinning are multifactorial, says Dr. Farhang, meaning that there are often a number of contributing factors. In terms of hair loss, the most common is genetics but can also be caused by other conditions such as "hormonal changes (i.e. giving birth or changing birth control pills], age, stress, vitamin/nutrient deficiencies, medical conditions, [or] medications that cause an excess of hair loss." 

Hair thinning can also be attributed to these factors, but "I often see it caused by certain hairstyling practices" says Dr. Farhang. This includes harsh chemicals and irritants or poor hair practices such as tight buns, hair coloring, and hair extensions.

She says it's best to consult with a dermatologist to identify the root (pun intended) cause of your hair loss or thinning. 

What Are the Best Products For Hair Growth?

There are a number of options out there when it comes to hair growth, from shampoos to oils and serums, but it's all about what ingredients these products contain. Dr. Farhang recommends looking for topical products with FDA-approved minoxidil, peptides, keratin, saw palmetto, rosemary oil, and pumpkin seed oil. She also recommends products that rebalance the scalp's microbiome, because a healthy scalp equals healthy hair.

Each ingredient can help with specific factors that are contributing to hair loss, which is why understanding why you are experiencing hair loss and thinning is so crucial.

One thing Dr. Farhang can't stress enough? Patience. "It takes time to see results. I would give any recommendations at least 6 months to start seeing a difference although some may see results sooner."

This serum contains peptides, an ingredient Dr. Farhang recommends. The leave-in formula improves hair density by thickening hair strands.

This TikTok viral rosemary oil is popular for a reason. It has anti-inflammatory properties, improves circulation, and inhibits DHT, a testosterone-derived hormone that can contribute to hair loss. This best-selling oil has 53,300+ 5-star reviews on Amazon.

The always popular Rogaine contains FDA-approved minoxidil and is one of Dr. Farhang's top recommendations, saying this ingredient "dilates the blood vessel to the hair follicle increasing blood flow, extends the duration of the hair follicle growth phase, stimulates new hair follicles and thickens the hair strands." She says to use it 1-2 times per day to help with hair growth.

According to Dr. Farhang, a buildup of oil and product in your scalp can contribute to hair loss, which is why this shampoo by Nutrafol is so effective. It helps rebalance the microbiome and provides a deep cleanse without stripping your hair.

"A scalp that is full of sebum/oil, tons of dry shampoo, etc. causes inflammation," says Dr. Farhang, which can contribute to hair loss. For a clean scalp, use this shampoo that gently removes buildup and clears hair follicles to stimulate growth.

Pair the shampoo with this conditioner, which strengthens, hydrates, and detangles hair to prevent breakage. It smells like a delicious blend of florals, citrus, and herbs as an added bonus.

Similarly to rosemary oil, pumpkin seed oil is anti-inflammatory, improves circulation, and inhibits DHT, a hormone that contributes to hair loss, promoting a healthy scalp and stimulating hair growth. 

"Topical products formulated with peptides are helpful for those experiencing hair thinning/breakage," says Dr. Farhang. This treatment fortifies hair follicles to improve hair density.

Infused with peptides, this serum stimulates your roots and increases the thickness of each strand to improve thinning hair for fuller, thicker looking locks.

If you're experiencing hormone-related hair loss, Dr. Farhang recommends topical saw palmetto, as it inhibits DHT, "a hormone derived from testosterone that plays a role in both male and female pattern hair loss." This oil contains saw palmetto in addition to pumpkin seed and rosemary oil. 

While sleeping on satin pillowcases won't help with hair growth, Dr. Farhang says it will help decrease breakage to give an overall healthier appearance to hair.

"Anything that decreases stress to the hair/scalp is ideal for hair regrowth," says Dr. Farhang. She likes scalp brushes and massagers like this one "because they stimulate circulation" which helps promote hair growth.

According to Dr. Farhang, "a good red light therapy cap for hair loss as it is proven to help on a cellular level." This one is her top pick.

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