Recently, the legions of acne scientists seem to have been delving into weird and wacky acne remedies from obscure parts of the globe.
We’ve had impepho, the twigs of a South African bush growing at grassy hillsides, which is burnt in superstitious rites. We’ve had Asian hornbeam, a swaying tree found in Chinese parks and university campuses.
Tamanu oil is another popular acne remedy, but if wasn’t for the wonders of international trade you’d have to travel to a Polynesian island and whack it out of a palm tree.
However, just as many great acne remedies aren’t obscure in the slightest. Sweet potatoes are popular in all cultures, from American thanksgiving dinners to Kitavan islanders.
Raw honey is the health remedy that will never be forgotten, and you could probably buy vitamin C from the summit of Mount Everest if you really put your mind to it.
Now, thanks to a new study published a few months ago in November 2019, a new contender may have joined their ranks – water spinach.
What is water spinach?
Ipomoea aquatica is a green, leafy plant, which is eaten as a vegetable all over Asia. The second word is inaccurate; there is no relationship to the traditional spinach vegetable. The first word is accurate, as its favourite habitats are shady swamps, rivers, and ponds.
Swamps covered with water spinach are particularly popular with endangered Chinese pond turtles, although you might see a pair of freshwater crocodile eyes blinking at you too. The plant loves damp soils and adores marshy and clay soils. There’s nothing that water spinach fears more than frost and temperatures below 23.9C.
Water spinach also has a secret weapon called a “labyrinth seed”. It sounds like a Bond villain’s plot to infect the population (in return for 100 billion dollars), but they’re really air bubbles that allow the green plant to float down rivers.
You can find water spinach growing all over the world, from Texas to Nigeria to Malaysia, but where it originated is a mystery. The oldest confirmed reference came from Ji Han in China, who lived during the Chin dynasty (A.D. 290-307). He references a green, matted plant clearly identifiable as water spinach, calling it a “strange vegetable of the south” for people in China’s north. The traditional Chinese name is kangkong, which is one letter away from a lawsuit from Universal Studios.
One old story states that water spinach arrived in Taiwan when people fled an unnamed murderous tyrant “many centuries ago”. Supposedly, water spinach, hastily picked from the riverbanks, was the only crop that could withstand the rocky boat voyages and keep the refugees well nourished.
There’s also the famous explorer Chen Shen, who launched 8 expeditions from 1405 to 1433. Records confirm that he carried wéng cài, another term for water spinach. As he travelled to Yemen, Egypt Somalia and Yemen, he carried barrels of rice with him, but also entire beds of uprooted earth, to grow vegetables. Historians theorise that he spread water spinach wherever he docked, as Yemen was where Forsskåll first discovered the plant and named it in 1775.
More recently, the easily growable water spinach became a not-so-beloved survival staple during World War 2, when Japanese forces occupied Singapore.
The plant’s growth rate is phenomenal; in the perfect conditions, the stems can grow by 10cm daily, to reach a maximum of 70cm. Entire ponds can be cloaked in a thick green netting so that other plants are starved for sunlight and boats can no longer sail through. Some claim that kangkong translates to “it is restless”.
In the US, it was once proudly featured in a list of the top 10 invasive species. In particular, water spinach has conquered the state of Florida. By 1973, possession of it became a jailable offence, but Asian communities have been secretly dealing it under the nose of the authorities.
The police have even bashed in people’s doors on water spinach raids, searching for secret stashes. Eco warriors have managed to eradicate it from several public lakes, which were becoming choked out and stagnant, creating the perfect breeding ground for mosquitoes.
Amidst all this madness, a new cure for acne may be hiding…
The study
Scientists tested a whole plant extract, rather than one isolated component which doesn’t give the full picture.
Fresh water spinach was picked in Ciwidey, Bandung, West Java, a cool region of Indonesia with vast flowing rivers which is popular with riverboarding tourists. Whether they simply ordered them or went on an epic voyage across the globe like Chen Shung is a mystery.
Anyway, they created three different extracts, using 1) ethanol, 2) ethyl acetate, and 3) the toxic solvent hexane. For comparison, they used the antibiotic tetracycline hydrochloride. This was one of the first antibiotics dermatologists ever prescribed; tetracycline was first sold in the US in 1954, and by 1976, 10% of all sales were for acne. It also kills a vast range of bacteria, so it’s perfect to compare to.
Scientists tested three different strains of bacteria: Escherichia coli, staphylococcus aureus, and propionibacterium acne. The latter is the acne villain which is hiding on your face and plotting a fresh batch of pimples at this very moment, by triggering an inflammatory immune system response. E.coli is gram negative while s. aureus is gram positive; because p.acnes is also gram positive, scientists were trying to ascertain which family water spinach specialises in.
P.acnes was incubated at 37 degrees celcius, a smart decision, as that’s the bacteria’s optimal habitat. Placing the petri dish in a cold and damp cellar would be no good, as the ambient conditions would do more work than the remedy, distorting the results.
The results
It was a bad day at the office for p.acnes. The first test was the inhibition zone, the circular area surrounding the remedy which was inhospitable to bacteria life.
The ethyl acetate extract inhibited p.acnes most strongly, and the diameter of the inhibition zone was 27.67mm, which could cover most of your nose. With ethanol-extracted water spinach, it measured 25mm, but the inhibition zone was clearer, with less remaining p.acnes stragglers.
Hexane extraction was the weakest, failing to reduce s.aureus at all. This makes sense, as hexane is so toxic and harsh that it obliterates natural phytonutrients; it’s why I never recommend factory produced soybean oil or canola oil.
Hexane-extracted also failed to inhibit s.aureus even slightly, but the ethanol (22.78mm) and ethyl acetate versions (29.56 mm) were excellent. By contrast, they inhibited e.coli much less, with 7mm for ethanol, reinforcing the gram positive theory.
A high tech microscope revealed that none of the inhibition zones were 100% clear. Thus, they concluded that water spinach is a “bacteriostatic” herb; it specialises in halting the growth of bacteria rather than killing every last specimen.
A great methodological advantage was that when tested in isolation, none of the three extraction solvents had any antibacterial properties of their own. The acne benefits rested entirely on waster spinach’s shoulders.
The final figures were that for inhibiting p.acnes, 1163.87 µg of water spinach (ethanol extract) were needed to match 1 µg of tetracycline. That sounds feeble, but the density of water spinach within the ethanol extract was a mere 0.78%. Therefore, when adjusted to the tetracycline’s complete purity, we have the much healthier figures of 1ug vs 9.55. It’s very similar for two other testing methods, the MIC and MBC, which are closely related but different.
Minimum inhibitory concentration (MIC) measures the lowest concentration that inhibits bacterial growth after 18-24 hours, while the minimum bactericidal concentration (MBC) is stricter, the lowest amount that kills 99% of the microorganism after 24 hours. For the ethanol extract (the best for both), the MIC for p.acnes was 1280 µg/ml while the MBS was 5120 µg/ml. For tetracycline, the figures were 2 µg/ml and 128 µg/ml.
However, adjusted for density again, water spinach ascends to an MIC and MBC of 9.984 µg/ml and 39.94µg/ml respectively.
Water spinach cannot match tetracycline, the biggest bully in the playground, but you wouldn’t expect it to either. Antibiotics are finely crafted pharmaceutical weapons, a little too finely crafted; they can obliterate the healthy strains on your face and in your gut. Meanwhile, water spinach comes with a free batch of antioxidants, phytonutrients and enzymes, with no terms and conditions…
Antioxidant mania
…which was another aspect of this study. Scientists analysed the chemical profile of water spinach leaves from top to bottom.
What did they discover? A coded message revealing who really assassinated JFK. No, they actually found numerous flavonoids, phenolic compounds, tannins, saponins, steroids, and triterpenoids. Not the type of steroids where you have to rotate 90 degrees to move through a doorway, but bioative plant hormones which stimulate various receptors.
It’s known that water spinach is particularly rich in quercetin, with 200.5mg per 1kg of dried weight. Some of these compounds could be the saviours, or it could something unique.
For example, quercetin’s most famous medicinal property is lowering histamine, the allergy chemical behind runny noses. However, in this study on six plant antioxidants, quercetin strongly suppressed the hospital-stalking MRSA bacteria, with an MIC of 125. It equalled luteolin (125) defeated the red wine antioxidant resveratrol (1000), and blew apigenin, scutellarin and chlorogenic acid (from coffee) out of the water.
Quercetin has two known powers. Firstly, it interferes with DNA gyrase (study). This enzyme coils up bacteria’s DNA in a rightward direction, making it essential for survival. For example, without it, bacteria loses the ability to replicate properly. Quinolone antibiotics like ofloxacin work in part by targeting DNA gyrase.
Secondly, quercetin may punch holes in a bacteria’s structure; it increases the permeability of its cell membrane. It disrupts the movement of protons across the membrane that bacteria requires to synthesise ATP energy. Consequently, under a microscope, quercetin can decrease the movement of individual bacteria cells (study). These facts were originally discovered during an experiment on bee propolis.
Could quercetin be behind water spinach’s antibacterial properties? If it is, then it raises an automatic problem: quercetin is a very common phytonutrient. It is abundant in sweet potatoes, onions and kale alike.
Therefore, there would be no need to cross the deserts of Afghanistan, slash through an Indian jungle, and sail in a wooden boat to the Indonesia to acquire this plant. However, there are numerous other candidates. For example, the tannin class of antioxidants is known to bind to the cell walls of bacteria.
From there they decrease adhesins, enzymes that bacteria use to stick to surfaces, and also protease enzymes. Water spinach is rich in flavones, which can form complexs with bacterial proteins and give them a wonky, malfunctioning structure.
The explanation of water spinach still isn’t nailed down, but we have some solid theories.
Any flaws?
The scientists wrapped up the study with enthusiasm, stating that “Ethanol water spinach herbs extract could be exploited as a natural medicinal alternative therapy for acne vulgaris“.
But will water spinach really be a revolution, or should we deflate the balloon of excitement right here, right now?
“Kills acne bacteria” is a great verdict in itself, but water spinach doesn’t seem exceptional relative to other plants. It’s decent, but it’s not like the p.acnes instantly exploded into a mass of cytoplasm upon contact.
Something they didn’t test was biofilm destruction, unlike in the recent study on the mystical African herb impepho. Biofilms are when bacteria secrete glycolax slime and create tough structures which are nearly impossible to remove. It’s when bacteria starts to cooperate, like p.acnes’ version of a giant swarming anthill. This can happen on both medical instruments and human skin.
Cutting through biofilms is phase 2 of your anti-p.acnes program, but we have no info for water spinach. Impepho, an incense which tribes burn to communicate with ancestors after sacrificing a goat, actually cut through biofilms more effectively than tetracycline, which it was also tested against (tetracycline was victorious for p.acnes numbers though). It even multiplied the antibacterial power of benzoyl peroxide six-fold.
Then there’s other powers. For example, the recent study on Asian hornbeam showed improvement in oily skin, inflammation and hyaluronic acid enzymes. Water spinach just has a run of the mill antibacterial study.
Some older studies were contradictory as well. For example, this study agreed that water spinach is a specialised slayer of gram positive bacteria, again wiping out s.aureus over e.coli, but this study found the opposite. Similarly, this study confirmed the wondrous elixir of phytonutrients hiding inside the leaves, but in this study, the saponins and steroids were absent. The explanation for both could be different growing locations. With a vast network across Asia, Africa and Oceania, anything is possible. As a plant that favours the damp, the cool, and the murk, particularly cold conditions could decrease its automatically generated antioxidant shield, by reducing the stress of the sunlight it seems to avoid, and its accompanying UV radiation. Some riverbanks will simply have more nutritious soil. Maybe its uncontrollable overgrowth depletes the nutrients of some river shores.
The methodology of this study was perfect. The problem is the limited scope, the things they didn’t address, and the insignificance in the grand scheme of acne.
Conclusion
So with great annoyance, our verdict is the blandest one imaginable: water spinach has potential for acne, but more studies are required.
My gut instant says that water spinach will never be miraculous for acne, but I’ll be happy to be proven wrong.
The final question is whether eating this thing will protect against your acne. Unlike Asian hornbeam or impepho, water spinach is found on dinnerplates across the globe. The Filipinos fry the leaves in flour-based batter to create a snack known crispy kangkóng. In Thailand the leaves are eaten raw in a salad alongside green papaya leaves. Malaysians and Indonesians prefer to stir fry them with garlic, shrimp paste and chilli pepper.
Could water spinach munchers have decreased rates of acne? The best we have is a study from Malaysia. In Malaysia, “kangkung” is ubiquitous. In 2014, the prime minister was even mocked all over social media in “kangkung gate”, when he said the country couldn’t possibly be experiencing economic woes, because the price of water spinach had fallen slightly.
Our study examined the faces of 409 high school students across 2 schools in the town of Muar. The verdict was that 67.5% of them had acne. 71.1% of males had acne compared to 64.6% of females, with the males having more severe acne. There is no magical bubble here.
Still, if it’s down to the phyonutrient profile, then adding it to the diet like broccoli or real spinach could easily work. The quercetin would diffuse to the p.acnes in the bloodstream or accumulate there in skin cells, making your skin a much less cosy place for p.acnes to inhabit.
Thanks for reading!