Dr Des Corrigan looks at the science behind herbal solutions for the predictable problem of January hangovers
“The year began with lunch” — so begins Peter Mayle’s wonderful A Year in Provence. For many others, a more accurate sentence is likely to have been ‘the year began with a hangover’. Hangovers are the painfully inevitable price we pay for our love affair with ethanol and many ‘cures’, with varying success rates, have emerged over the centuries. A recent RCT of the efficacy of a ‘food for special medical purposes’ (a food supplement) in reducing hangover symptoms appeared in BMJ Nutrition, Prevention and Health.
The technical term for a hangover is ‘veisalgia’, comprising all physical and psychological symptoms perceived on the day after use of ethanol. These symptoms increase in intensity as the alcohol is metabolised and may last for up to 24 hours. Caused by the alcohol itself; other chemicals in the beverage called congeners and metabolic intermediates such as acetaldehyde, the most frequent symptoms are exhaustion (96 per cent), thirst (89 per cent), fatigue (88 per cent), headaches (88 per cent), dry mouth (83 per cent) and nausea (81 per cent).
The study involved 214 male and female participants who were given either the entire food supplement (FSMP) containing plant extracts, vitamins, minerals and antioxidants or a dietary supplement containing only the vitamins, minerals and antioxidants, or a placebo containing only glucose. They were allowed to drink as much as they wished of their choice of beer (4.8 per cent alcohol), white wine (11 per cent) or white wine spritzer (5.5 per cent) between 5pm and 9pm. After a night’s sleep, the Acute Hangover Scale (AHS) was determined based on 47 different symptoms.
Headache intensity for the placebo group was 2.97 compared to 1.99 for the FSMP group, and nausea intensity was 1.17 for the FSMP, compared to 2.03 for placebo. The authors reported no significant improvement in hangover symptoms with the dietary supplement, whereas the FSMP gave a number of positive effects that they claim are likely due to the plant extracts in the product.
So what are those plants with these ‘magic’ properties? There are five of them, namely: Malpighia glabra, Opuntia ficus-indica, Ginkgo biloba, Salix alba, and ginger. At first glance, two of these make sense in a hangover cure, namely the willow leaf (Salix) and the ginger. Most willows contain salicin-type compounds that are essentially pro-drugs, as they are glycosides made up of glucose linked to salicyl alcohol. That salicyl alcohol is released in the stomach by acid hydrolysis.
Once absorbed, the salicyl alcohol is then metabolised to salicylic acid in the liver. The body does not distinguish between the analgesic and antipyretic effects of ‘natural aspirin’ from Willows and the chemically identical though synthetic acetylsalicylic acid, even if the onset of action might be slower.
Willow also has the advantage that neither salicin nor salicyl alcohol are gastric irritants. Normally, willow bark is used medicinally, rather than the leaf. According to the EMA’s Herbal Monograph, a dry extract of willow bark containing 15 per cent of total salicin has a ‘Well-Established Use’ (WEU) as a herbal medicinal product for the short-term treatment of low-back pain.
Other preparations and extracts have an indication claim as traditional herbal medicinal products for the relief of minor articular pain and of the fever associated with the common cold. It would appear, therefore, that including willow in a hangover remedy is highly plausible scientifically.
The same applies to ginger, with its mix of gingerols and shogaols. According to the EMA, ginger has a WEU as a herbal medicinal product for the prevention of nausea and vomiting in motion sickness. That WEU is based on clinical data, not just tradition, and pharmacological plausibility so the evidence that ginger is an antiemetic is strong.
The EMA does also accept a traditional use for symptomatic relief of motion sickness and in the treatment of mild, spasmodic gastrointestinal complaints, including bloating and flatulence. I have no doubt, therefore, that the presence of ginger in a hangover formulation to reduce nausea is justified.
It is more difficult to see a rationale for the inclusion of ginkgo biloba in the formulation. I recognise that ginkgo extracts, with their mix of diterpenoid ginkgolides and ginkgo flavones are pharmacologically quite potent in their effects as platelet-activating factor inhibitors, for example.
The EMA has agreed a WEU designation for standardised extracts for the improvement of (age-associated) cognitive impairment and of quality of life in mild dementia — again based on clinical trial data. One wonders how this might be relevant to a hangover. Admittedly, ginkgo constituents are quite powerful antioxidants and this activity might be relevant. In addition, there are well-recognised cognitive effects of alcohol the morning after a drinking episode, where learning and memory do not return to normal until about lunchtime.
Whether a one-off dose of ginkgo extract could reverse that does need more research, as one would normally need to consume a ginkgo product for several weeks before seeing any impact on cognitive impairment.
What then of the two lesser-known plants in the product? The fruits of malpighia are better known as Acerola, Barbados or West Indian Cherry.
It is native to Central and South America, but cultivated in many tropical and sub-tropical countries because of its exceptionally high content of vitamin C. Typical vitamin C content in fresh berries is 1.67g per 100g of fruit, although concentrations up to 4.5g have been recorded. This is 50-to-100 times more than in oranges or lemons. A Japanese study in 2011 indicated that absorption of ascorbic acid in Acerola is greater than vitamin C on its own due to the influence of other juice components.
Pharmacological studies suggest antioxidant (not surprisingly), antimicrobial and hypoglycaemic activity.
Opuntia is a cactus-like plant also known as ‘Prickly Pear’. The juice is reported to inhibit ulcerogenesis in rats through an increase in mucous secretion and restoration of normal mucosa that might indicate a beneficial effect on upset tummies arising from over-indulgence in alcohol.
There have been a number of clinical studies showing that LDL-cholesterol was lowered. Clinical studies showed a hypoglycaemic effect in type-2 diabetes patients, but a meta-analysis of RCT data of Prickly Pear as a weight loss aid did not suggest that it had any significant effect on body weight.
It would appear that the effects of this supplement are largely due to the willow and ginger components. It does
look like a promising product, but when it comes to drinking, I am reminded of the advertising slogan, ‘enjoy alcohol responsibly’ and even more so of the cliché, ‘all things in moderation!’ As ever, prevention is better than cure.