Dr Nigel Dowdall, British Airways medical advisor, replies: There are several factors to take into consideration, such as the time and the length of the flight and jetlag is very dependant on the individual, but there are a few things you can do to try and alleviate the symptoms.
You don't say how long you are in the States for, but as you go there often I assume it must be on business. If this is the case and you're only there for a few days, don't acclimatise to the time zone. Instead, try to stick to your normal routine - eat lunch at UK time and sleep when you would normally sleep. Obviously this isn't always practical, but it's about getting as close to the recommended eight hours in a 24 hour period as you can. The best time to sleep is in the mid to late afternoon, when many of us feel drowsy anyway, which will help to ease physical tiredness. But if you stick to your usual routine you'll have no problem readjusting.
Some other points that may help are avoid alcohol on the plane, drink lots of water and nap as much as possible. Melatonin, which supposedly alleviates jetlag, should be approached with caution. Production of the drug isn't regulated yet, so you don't really know what you're buying.
Travel health clinics, if given an itinerary and background information on a patient, can come up with more specific ways of dealing with jetlag.
For British Airways travel clinics check out www.ba.com.