Prince Charles has claimed that people struggling to return to full health after having the coronavirus should practice yoga. This is what the GUARDIAN reported about it on Friday:
In a video statement on Friday to the virtual yoga and healthcare symposium Wellness After Covid, the heir apparent said doctors should work together with “complementary healthcare specialists” to “build a roadmap to hope and healing” after Covid. “This pandemic has emphasised the importance of preparedness, resilience and the need for an approach which addresses the health and welfare of the whole person as part of society, and which does not merely focus on the symptoms alone,” Charles said. “As part of that approach, therapeutic, evidenced-informed yoga can contribute to health and healing. By its very nature, yoga is an accessible practice which provides practitioners with ways to manage stress, build resilience and promote healing…”
… Charles, who has previously espoused the benefits of yoga, is not the only fan in the royal family. His wife, the Duchess of Cornwall, has said “it makes you less stiff” and “more supple”, while Prince William has also been pictured doing yogic poses. In 2019, the Prince of Wales said yoga had “proven beneficial effects on both body and mind”, and delivered “tremendous social benefits” that help build “discipline, self-reliance and self-care”.
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Yoga is a complex subject because it entails a host of different techniques, attitudes, and life-styles. There have been numerous clinical trials of various yoga techniques. They tend to suffer from poor study design as well as incomplete reporting and are thus no always reliable. Several systematic reviews have summarised the findings of these studies. A 2010 overview included 21 systematic reviews relating to a wide range of conditions. Nine systematic reviews arrived at positive conclusions, but many were associated with a high risk of bias. Unanimously positive evidence emerged only for depression and cardiovascular risk reduction. There is no evidence that yoga speeds the recovery after COVID-19 or any other severe infectious disease, as Charles suggested.
Yoga is generally considered to be safe. However, a large-scale survey found that approximately 30% of yoga class attendees had experienced some type of adverse event. Although the majority had mild symptoms, the survey results indicated that patients with chronic diseases were more likely to experience adverse events. It, therefore, seems unlikely that yoga is suited for many patients recovering from a COVID-19 infection.
The warning by the Vatican’s chief exorcist that yoga leads to ‘demonic possession’ might not be taken seriously by rational thinkers. Yet, experts have long warned that many yoga teachers try to recruit their clients into the more cult-like aspects of yoga.
Perhaps the most remarkable expression in Charles’ quotes is the term ‘EVIDENCE-INFORMED‘. It crops up regularly when Charles (or his advisor Dr. Michael Dixon) speaks or writes about so-called alternative medicine (SCAM). It is a clever term that sounds almost like ‘evidence-based’ but means something entirely different. If a SCAM is not evidence-based, it can still be legitimately put under the umbrella of ‘evidence-informed’: we know the evidence is not positive, we were well-informed of this fact, we nevertheless conclude that yoga (or any other SCAM) might be a good idea!
In my view, the regular use of the term ‘evidence-informed’ in the realm of SCAM discloses a lack of clarity that suits all snake-oil salesmen very well.
 Ernst E, Lee MS: Focus on Alternative and Complementary Therapies Volume 15(4) December 2010 274–27
 Matsushita T, Oka T. A large-scale survey of adverse events experienced in yoga classes. Biopsychosoc Med. 2015 Mar 18;9:9. doi: 10.1186/s13030-015-0037-1. PMID: 25844090; PMCID: PMC4384376.