White willow bark supplement: fortifying & soothing

Willow Bark Extract is an analgesic and cardioprotective supplement made from white willow bark. It’s a gentler, safer and longer-lasting alternative to the drug aspirin. Over the past few months, it has been attracting extraordinary interest for its clinically proven synergistic power, naturally high salicin content and durable effects on chronic pain and circulation.

What’s the reason for this phenomenal rise in interest in white willow extract?

The use of willow bark for medicinal purposes spans centuries and civilisations. From Imperial China to First Nation America, Ancient Greece to medieval Europe, willow bark has been widely used to soothe pain and bring down fever (1).

In 1828, Pierre-Joseph Leroux, a French pharmacist, thought he had identified the active substance behind these effects: salicin. It was quickly discovered that this substance was converted in the body into salicylic acid, a compound with clear analgesic and antipyretic properties. There then followed a frantic race to be the first laboratory to synthesise the molecule. It was a German chemist working for the Bayer group who succeeded in doing so, producing for the first time a derivative of salicylic acid (acetylsalicylic acid) without using willow bark. Named ‘aspirin’, the drug would go on to enjoy rapid success, consigning willow bark to oblivion … for almost 120 years.

But for some time now, white willow extract has been experiencing a surprising and extraordinary comeback. Why so? In actual fact, Pierre-Joseph Leroux had made a mistake. While salicin is indeed an active compound in willow bark, it is by no means the only one! There are dozens of other natural molecules that act synergistically and complement the effect of salicin (2-3): proanthocyanidins (extensively metabolised by our gut flora), anti-inflammatory flavanones (naringenin, eriodictyol) (4-5), flavonoids (dihydroquercetin), flavonols (catechin) and polyphenols (caffeic, ferulic, cinnamic, vanillic, hydroxybenzoic and coumaric acids). And it’s the combination of these natural compounds that is responsible both for the anti-inflammatory effects of white willow extract, and its antioxidant, antiseptic, and immune-stimulating effects (6). A number of studies have shown blood levels of salicin to be too low to account exclusively for the analgesic effects of this extract (7-8).

In isolating one of these natural compounds, and offering it in an already-metabolised synthetic form, Bayer undoubtedly produced an effective painkiller, but it is one which is associated with significant side-effects. Its unique mechanism of action requires enormous amounts of salicylic acid which in the long term can damage the body (particularly in terms of gastrointestinal bleeding). In contrast, willow bark’s efficacy comes from a range of anti-inflammatory mechanisms of action and does not directly expose the digestive tract to acetylsalicylic acid. Willow bark extract thus contains a dose of salicylic acid which is potentially 10 times lower than that of standard aspirin tablets, but with physiologically comparable effects.

What are the main benefits of willow bark extract?

Willow Bark Extract offers anti-inflammatory, analgesic and cardioprotective effects. It is particularly good for:

• Those suffering from acute or chronic pain (headaches, back pain, arthritic pain, menstrual cramps, ‘flu …). Scientific research has clearly demonstrated white willow’s efficacy in relieving chronic and acute pain. A summary published in 2007 concluded that white willow was effective for lumbar pain (13) when taken for around four weeks. Studies similarly show its effectiveness for arthritic pain, particularly in the knee and hip (14-15). The authors point out that its effects take longer to be felt than those of anti-inflammatory drugs, but that they produce far fewer adverse side-effects. In 2009, a research team drawing on three major clinical studies showed white willow extract to be effective against muscle pain (16).
• Those aged over 50, for reducing the risk of cardiovascular problems, combatting oxidative stress and improving general health. Low-dose aspirin (or ‘baby aspirin’) has for many years been recommended for preventing cardiovascular disease and stroke in those over 50, especially individuals with several risk factors. The action of salicylic acid prevents blood clots from forming and thus reduces the risk of a cardiovascular event. The United States Preventive Services Task Force (USPSTF), an independent group of American researchers, confirmed this anew in 2016: the benefits they measured show that for 10,000 men presenting with a 10% 10-year cardiovascular risk, aspirin prevents 225 heart attacks, 84 strokes and 139 cases of colorectal cancer. That’s a gain of more than 300 years of life. For a few years now, however, some researchers have held the view that the benefits of aspirin may not always outweigh its adverse side effects (particularly the increased risk of bleeding). Gentler and more comprehensive, extract of willow bark thus appears to be the perfect alternative to aspirin for those who want to reduce their likelihood of a cardiovascular event without exposing themselves to other health risks.

How does willow bark extract differ from the drug aspirin (acetylsalicylic acid)?

There are three main differences between the two.

1. Willow bark acts more slowly than acetylsalicylic acid in relieving pain but its effect is sustained over the long term.
2. Willow bark extract does not cause the unwelcome side effects (irritation of stomach mucosa and inhibition of coagulation) associated with acetylsalicylic acid. The plant is metabolised very differently from its synthetic counterpart (9). This characteristic lends itself well to multi-target therapy, a new therapeutic approach which focuses on exerting physiological effects by means of a combination of targets rather than the action of a single, high-dose molecule. Scientists have observed that this type of therapy has been able to reduce and even eliminate side-effects because of the lower individual dose of the active compounds (10-12).
3. Willow bark extract also offers antioxidant, anti-infectious, immune-stimulant and invigorating properties.

What are white willow extract’s mechanisms of action?

Salicin’s mechanism of action remained a mystery for many years. It was only in 1971 that John Vane and his team at the Wellcome Foundation showed that it prevented the action of certain enzymes - COX-1 and COX-2 - involved in metabolising arachidonic acid. These enzymes promote the first stage in the formation of a group of eicosanoids - signalling molecules involved in inflammatory processes.

By blocking the action of these COX enzymes, salicin lowers the production of a number of inflammatory mediators which are responsible for pain, swelling and other symptoms associated with inflammatory processes. Inhibition of COX-1 also reduces levels of thromboxane, a vasoconstrictor which leads to increased blood pressure. It is this mechanism of action which explains the use of low-dose aspirin for lowering the risk of heart attack (17). A number of studies have shown that salicylic acid also interacts with RNA and coenzyme A, opening up a potential application in the area of oncology (18).

All the other compounds in willow extract have complex and complementary cell mechanisms, indirectly inhibiting the pro-inflammatory cytokines TNF-alpha and interleukin-6, inhibiting translocation of the protein NF-kB (19), and inactivating transcription of certain genes associated with inflammation.