Congratulations, you've made it in to work, but all you want to do is crawl under your desk and hide. You need energy, and fast. Ginseng is one of the natural world's most powerful energy tonics, and has been used for nearly 5,000 years for its strengthening and rejuvenating properties. There have been more than 3,500 studies into ginseng's efficacy, and these have found it to fight depression, enhance vitality and performance ( sexual included), help concentration and reduce the incidence of heart disease. But be warned: not all ginseng is created equal and, in many cases, you get what you pay for. Available from the Nutri Centre, 0800 587 2290, www. nutricentre.com.