The Saturday Scalpel: Issue 13

The DIY Hair Growth Serum That Doesn’t Smell Like Regret

Author

Dr. Max Maddahali
August 02, 2025 • Estimated Reading Time: 5 minutes

From the Desk of Dr. Kevin, MD

"I tried patience once. It didn’t work fast enough."

Hello, Scalpheads. Time for some unsolicited science.

It’s your boy again, Kev… Back again to roast your hairs.

Let’s talk about the cure for hair loss hiding in your kitchen.

No, it’s not collagen powder or that expensive bottle of unicorn tears.

It’s onions.

The thing that makes you cry might just bring your scalp back to life.

Before you gag, hear this:

Onion juice contains two powerful things your hair follicle loves.

One is sulfur, which is essential for producing keratin, the structural protein that makes up your hair.

The second is quercetin, a plant flavonoid that’s an anti-inflammatory, immune modulator, and antimicrobial all at once.

That means it helps:

  • Block autoimmune attacks (think alopecia areata)

  • Calms down angry scalp conditions

  • And improves blood flow to the follicles.

In other words, it creates a thriving environment for hair to grow again.

Alopecia areata

Still skeptical? Fantastic.

A 2002 study in the Journal of Dermatology showed that onion juice led to hair regrowth in 86.9% of people with patchy hair loss in just six weeks.

The placebo group using plain water? Only 13% showed improvement.

Mice studies using isolated quercetin also demonstrated full regeneration of hair in the treated groups, while the untreated mice stayed bald and bitter.

Ready for the genius recipe?

Here’s the simple version:

  1. Blend a red onion (more quercetin than yellow).

  2. Strain the juice using cheesecloth.

  3. Apply to wet scalp.

  4. Massage for a couple minutes.

  5. Leave on for an hour under a shower cap.

  6. Shampoo twice.

  7. Repeat twice a week for six weeks.

  8. You’re welcome.

Now for the power-up: Add five drops of rosemary oil.

A randomized 2015 study found rosemary oil was as effective as minoxidil, the gold-standard alopecia drug. Max loves that shit…

Rosemary boosts circulation, reduces inflammation, and even tackles hormonal imbalance.

Want to get even fancier?

Ferment the onion juice. Yes you heard me.

Mix blended onion juice with water, sea salt, and a bit of raw honey.

Let it ferment for 72 hours on your counter with a cheesecloth cover.

This boosts the quercetin concentration, adds scalp-friendly acids, and encourages probiotic activity.

The result is a potent, scalp-loving tonic with a natural pH around 5.

Now…

If you’re doing everything right and still seeing minimal growth, check your vitamin D.

Multiple studies show that vitamin D deficiency is linked to hair loss.

Aim for 10,000 to 20,000 IUs daily if your levels are low or spend some time in the sun.

And don’t forget to support your hair with real food: protein, healthy fats, and micronutrients matter.

Alright, that’s your scalpel to the scalp for today.

Now go do something bold—like rubbing onion juice on your head instead of buying your sixth “miracle serum” from that influencer with a wig.

Or skipping the hair transplant consultation you booked out of panic and giving your follicles an actual fighting chance.

You got this. Twice a week. Six weeks. Let’s make your scalp famous again.

Yours in caffeine, sarcasm, and cortisol,
Dr. Kevin Cutthebull, MD

P.P.S Got a weird hair growth tip your grandma swears by? Reply to this email and let’s investigate it together. We might roast it. Or we might turn it into next week’s scalp miracle.

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