The Medicinal Properties Of Bay Leaves

The humble bay leaf has more uses than just culinary!

How about for hair growth?

Popularly recommended on social media with the promise of long and glowing hair… Guess how many scientific studies back up this claim!

If you guessed zero, you guessed correctly. At least, we were not able to find any. In fact, the only paper on the entirety of PubMed (a large online database of available scientific literature from most, if not all, reputable scientific journals) to return a hit for the search string “bay leaf hair growth” was this one:

Suppression of Propionibacterium acnes-Induced Skin Inflammation by Laurus nobilis Extract and Its Major Constituent Eucalyptol

You may notice that that has nothing to do with hair growth, and rather returned the hit because the acne bacteria are known to “proliferate within sebum-blocked skin hair follicles”.

So let’s talk about that instead:

Against acne & skin inflammation

Well, for that, it works! The research that we mentioned above concluded that:

❝LNE significantly suppressed the expression of P. acnes-mediated proinflammatory cytokines, such as IL-1β, IL-6, and NLRP3. We also found that LNE inhibited the inflammatory transcription factor NF-κB in response to P. acnes. In addition, eucalyptol, which is the main constituent of LNE, consistently inhibited P. acnes-induced inflammatory signaling pathways. Moreover, LNE significantly ameliorated P. acnes-induced inflammation in a mouse model of acne. We suggest for the first time that LNE hold therapeutic value for the improvement of P. acnes-induced skin inflammation.❞

LNE = Laurus nobilis extract, i.e. bay leaf extract

Now, that’s all about acne-induced skin inflammation, but what about other kinds?

Against inflammation in general

Bay leaves have an abundance of antioxidant polyphenols, and what’s good against oxidation is good against inflammation. For example:

Laurus nobilis leaf extract controls inflammation by suppressing NLRP3 inflammasome activation

That anti-inflammatory action is more than skin-deep though, because…

Against IBD / ulcerative colitis

It’s good for the gut, too, for example in this study (with mice, but the bacteria affected are the same as we have), which found:

❝…bay leaves showed the best treatment effects on gut microbiota compositions; promoting the growth of Bifidobacteria and Lactobacillus in addition to producing high butyric acid levels. Meanwhile, the number of Clostridium and sulfate-reducing bacteria was significantly reduced. Conclusively, consuming bay leaves brought significant colon health benefits other than stimulating appetite for a better taste.❞

Read in full: Anti‐inflammatory effects of bay laurel (Laurus nobilis L.) towards the gut microbiome in dextran sodium sulfate induced colitis animal models

Note that all of those gut-related changes are beneficial to us, increasing things that are best increased, and reducing things that are best reduced.

Against diabetes

It’s good for the blood—and for the heart, but more on that later. First, about diabetes:

❝All three levels of bay leaves reduced serum glucose with significant decreases ranging from 21 to 26% after 30 d.

Total cholesterol decreased, 20 to 24%, after 30 days with larger decreases in low density lipoprotein (LDL) cholesterol of 32 to 40%. High density lipoprotein (HDL) cholesterol increased 29 and 20% in the groups receiving 1 and 2 g of bay leaves, respectively. Triglycerides also decreased 34 and 25% in groups consuming 1 and 2 g of bay leaves, respectively, after 30 d. There were no significant changes in the placebo group.

In summary, this study demonstrates that consumption of bay leaves, 1 to 3 g/d for 30 days, decreases risk factors for diabetes and cardiovascular diseases and suggests that bay leaves may be beneficial for people with type 2 diabetes.❞

Again, all those changes are good:

Bay Leaves Improve Glucose and Lipid Profile of People with Type 2 Diabetes

Good for the heart

This one’s quite straight forward. Bay leaf tea is indeed good for the heart,

• Literally: Evaluation of Daily Laurus nobilis Tea Consumption on Lipid Profile Biomarkers in Healthy Volunteers
• Metaphorically: Evaluation of daily Laurus nobilis tea consumption on anxiety and stress biomarkers in healthy volunteers

Of course, even that latter is also good for the heart literally, just, indirectly, by reducing anxiety and stress, thus indirectly benefiting the heart itself.

But even before that, it’s already very directly beneficial to cardiovascular health, per its significant improvements to the lipid profile.

Anything else?

So much else, but there’s only so much we can feature in one day, so if you’d like to learn more, we recommend this very comprehensive paper:

Chromatography analysis, in light of vitro antioxidant, antidiabetic, antiobesity, anti-inflammatory, antimicrobial, anticancer, and three-dimensional cancer spheroids’ formation blocking activities of Laurus nobilis aromatic oil from Palestine

…which discusses many benefits in considerable detail, including…

❝The LN leaves have various biological activities, such as antioxidant, wound healing, antibacterial, analgesic, and anti-inflammatory activities. However, oxidative stress, cancer, diabetes, microbial infections, and inflammatory diseases are closely linked. The objective of this research is to characterize Laurus nobilis (LN) aromatic oil (AO) and evaluate its antioxidant, antidiabetic, antiobesity, antimicrobial, and antimutagenic bioactivities.

The plant AO showed potent antioxidant activity (IC₅₀ = 2.2 ± 1.38) and has moderate anti-amylase (IC₅₀ = 60.25 ± 1.25), anti-glucosidase (IC₅₀ = 131.82 ± 0.1), and antilipase (IC₅₀ = 83.17 ± 0.06) activities.

Moreover, LNAO showed potent antimicrobial activity against Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, Proteus vulgaris (MICs = 1.56 µg/mL), methicillin-resistant Staphylococcus aureus (MRSA) (MIC = 3.125 µg/mL) and Candida albicans (MIC = 0.195 µg/mL). The cytotoxicity results demonstrated that at a concentration of 1 mg/mL, LNAO has potent breast cancer (MCF-7), and hepatocellular carcinoma (Hep 3B) cancer cells inhibitory activities of 98% and 95%, respectively.

Importantly, we are the first to show that LNAO significantly hinders hepatocellular carcinoma spheroids’ formation capacity in a 3D model.

These results show that LNAO is a promising natural source with powerful antioxidant, antidiabetic, anticancer, and antimicrobial activities that could be exploited in the future to treat a variety of diseases.❞

Want to try some?

We don’t sell it, but you can buy leaves from your local supermarket and make bay leaf tea, or alternatively, if you prefer essential oil form, here for your convenience is an example product on Amazon 😎

Enjoy!