Medically reviewed by Kristin Hall, FNP
Written by Our Editorial Team
Last updated 5/27/2021
Treating hair loss is a big industry -- one that’s projected to be worth almost $12 billion by the year 2024.
Just a few decades ago, treating hair loss and improving hair growth meant ordering products like special combs, and potions from catalogs. Today, it’s easy to find a range of products aimed at improving your hairline, thickening thin areas and fueling hair growth.
Despite this, the same question remains:
Like most industries, the hair loss prevention world features reliable, proven products that can actually prevent against hair loss and improve hair growth.
It features plenty of snake oil, unproven and products that generally aren’t worth your money.
Below, we’ve listed the most popular hair loss prevention and hair growth products available on the market.
For each product, we’ve looked at the scientific evidence to determine whether it’s an effective treatment that’s worth considering or something you should avoid.
Finasteride is a prescription medicine designed to prevent hair loss by blocking DHT, the male hormone that causes hair follicles to miniaturize and eventually stop growing new hairs.
Finasteride was introduced as a hair loss treatment in the 90s after several years as a treatment for BPH. You’ve probably seen finasteride advertised on TV or in magazines under the brand name .
By blocking testosterone from converting into DHT, finasteride prevents hair loss from occurring and helps you keep the hair you already have. Some men also notice a small number of "lost" hairs regrowing after taking finasteride, although this isn’t guaranteed.
Unlike most hair loss prevention products, finasteride works extremely well. Taking it on a daily basis reduces DHT levels by about 70%, which is enough to either stop or slow down the effects of male pattern baldness.
If your hair is receding or thinning, finasteride should be one of the first products you consider as a treatment option.
Minoxidil is a spray, foam or liquid solution that you apply to your scalp. Unlike finasteride, which stops hair loss by blocking the creation of DHT, minoxidil is a hair growth agent that’s designed to create the ideal conditions for hair growth in your scalp.
Studies show that use of minoxidil over a 48 week period results in a 12.7% to 18.6% increase in total hair count. If you have thinning hair, the extra thickness provided by minoxidil can make a big visual difference.
Since minoxidil doesn’t block DHT, it isn’t considered effective as a long-term prevention agent for stopping male pattern baldness. It’s best to think of finasteride as a shield against hair loss and minoxidil as a fertilizer for your existing hair.
Because of its scientifically proven effects, minoxidil is another hair loss product that should be near the top of your list of treatment options.
Some vitamins, such as vitamin A, vitamin and biotin, play a role in helping you grow a thick, healthy head of hair.
If you’re deficient in any of these vitamins, adding a vitamin supplement to your hair care stack can be a good idea. However, it’s important to be aware of the difference between vitamins that and pharmaceutical treatments that
Vitamins play a role in helping you grow healthy, strong hair, but they aren’t proven to have any effect on male pattern baldness.
Since male pattern baldness is the result of sensitivity to DHT, the only real treatment option is to block DHT using a product like finasteride.
This doesn’t mean that taking a vitamin supplement is a bad idea -- from a general health and wellbeing perspective, it’s usually a very good idea. Just don’t expect to reverse your receding hairline or other genetic hair loss by adding vitamins to your morning routine.
For more information on the best vitamins for hair growth, check out our Essential Vitamins for a Healthy Head of Hair guide.
Saw palmetto is one of the most popular ingredients in hair loss prevention supplements. It’s also one of the few supplement ingredients that’s actually proven to have some effect on the levels of DHT -- the hormone that’s responsible for hair loss -- in human tissue.
Studies of saw palmetto and finasteride show that saw palmetto has a measurable effect on DHT levels in the prostate. While this effect isn’t as strong as finasteride, it does show that a regular dose of saw palmetto could potentially lower the conversion of testosterone to DHT.
Does this mean you can replace finasteride with a saw palmetto supplement? Not quite. The evidence for saw palmetto is currently very limited, meaning you shouldn’t view it as a proven replacement for pharmaceutical DHT blockers like finasteride.
It’s also important to know that taking saw palmetto and finasteride together could result in an interaction between the two substances, meaning you should speak to your doctor before you consider using both products at once.
Hair growth shampoos with ingredients like ketoconazole, zinc, saw palmetto and biotin can have some impact on the speed at which your hair grows, and help your hair to grow faster, making them worthwhile additions to your hair care routine.
Instead of viewing hair growth shampoos as a whole, it’s best to focus on specific ingredients and their impact on hair loss. Ingredients like ketoconazole and saw palmetto are proven to have some effects on hair growth; others common shampoo ingredients might not be.
Before you buy a hair growth shampoo, make sure you check the label to see if the ingredients used in the shampoo are backed up by real science. Our What to Look For in a Men’s Hair Loss Shampoo guide contains a full list of the ingredients you should check for in a shampoo.
Some natural oils, such as pumpkin seed oil and rosemary oil, have been shown to have limited effects on hair growth in studies.
For example, daily supplementation of pumpkin seed oil produced a 40% increase in hair count over a period of 24 weeks, compared to approximately 10% for people given a placebo.
It’s worth noting that this study was originally published in . There is also very limited additional evidence for pumpkin seed oil’s value as a hair loss prevention substance. Still, it’s an interesting option to consider.
There is also limited evidence in support of rosemary oil as a hair growth treatment. One study from 2015 found that rosemary oil was equally as effective at improving hair growth over a six month period as minoxidil, making it an interesting natural treatment option for hair loss.
Will natural oils work as well as products like finasteride and minoxidil? At this point, there just isn’t enough research to view these products as proven hair loss treatments, especially on the same level as treatments with extensive scientific evidence like finasteride and minoxidil.
Laser combs and helmets, which use cooling lasers to promote hair growth, have appeared on the market over the last few years.
Most of these products promise some amount of hair growth as a result of exposure to the lasers, which supposedly improve blood flow to the scalp.
The scientific data behind these products is mixed, at best. One study showed that users of a laser comb reported an improvement in hair growth, with a moderate increase in hair count per square centimeter.
Some of the companies that manufacture and market these products recommend using them alongside hair loss pills such as finasteride for faster results. Right now, there isn’t any reliable scientific data showing that they have any synergistic effects with other hair loss treatments.
While laser combs, helmets and other products could potentially be effective for hair growth and preventing hair loss, the scientific evidence just isn’t there yet.
It’s best to proceed with caution when it comes to laser hair growth products, especially for anything marketed as a miracle cure.
Electric scalp massagers, which claim to improve hair growth by stimulating the scalp, are also best viewed with a certain degree of skepticism and caution.
These products are usually cheap (most are $25 or less on Amazon) but aren’t supported by any substantial scientific evidence
While there are studies supporting scalp massage as a hair growth treatment, most have major limitations that make them hard to take seriously.
For example, a 2016 study that’s occasionally cited as "proof" of head massage working has a sample size of just nine people.
Like with laser combs and helmets, the science just isn’t there to back up the claims of electric scalp massagers just yet. As always, you should be skeptical of any product that makes large claims without an equally large amount of evidence to back them up.
Insider tips, early access and more.