Know your numbers Following new research into the health benefits of fruit and vegetables, there are calls to up the current recommendation from five portions a day to seven. With five-a-day in question, how do other commonly quoted figures add up?


Sleep = 8 hours per night

The ideal quota has long been held to be eight hours, yet research from The Sleep Council has found a third of us get by on just five or six hours sleep a night.

“Eight hours does not apply to everybody – some people will need less sleep than others,” says Dr Sarah Jarvis.

“It also depends on your quality of sleep. If the amount of sleep you’re getting works for you, that’s great. However, if you’re prone to feeling tired, ask yourself how much sleep you’re getting. Some people will sleep for eight hours or more and wake up feeling unrefreshed. If you’re also overweight, this could be due to a condition called sleep apnoea, where you actually stop breathing and your quality of sleep is affected. If you’re already getting a lot of sleep yet still feel tired, you may need to have a chat with your doctor.”


Fruit & veg = 5 portions per day

Only one in four adults (and one in ten teenagers) in the UK manages to get five portions a day at present. Public Health England, however, says it has no plans to alter its guidelines following the findings of the University College London study.

“We tend to forget that the current advice is at least five portions of fruit and vegetables a day – we just focus on the number five,” says Azmina Govindji, dietitian and spokesperson for the British Dietetic Association.

“This new research is very welcome as it’s helping us to question our current intake. But I think we need to be practical and realistic as many of us are struggling to eat five-a-day as it is. It’s absolutely imperative that you eat as many as you can, especially veg, as the more you eat, the more protected you are. Think about what you’re currently eating and if you can add one more vegetable portion a day, this will make a difference.”


Blood pressure = 100 plus your age

“This advice is very outdated and doesn’t apply now,” says Dr Rob Hicks, a practising GP and author of Control Your Blood Pressure.

“Your blood pressure needs to be at or below 120/80. When you consistently have a reading of 140/90, you have high blood pressure. There are no more excuses for people adding their age to 100 and thinking they’re fine when they get a higher reading – that is wrong.”


Water = 8 glasses per day

The widely held belief that we need eight glasses of water a day doesn’t take into account the hydrating effects of other drinks or, indeed, the water content of many foods.

“This advice is just plain wrong,” says Dr Sarah Jarvis, a practising GP and TV doctor.

“You need to have enough fluid each day (1.5 to 2 litres) but it doesn’t have to be just in the form of water. All drinks (apart from alcohol which dehydrates you) count towards your intake, including tea and coffee, though you should try to avoid sugary drinks.”

This article first appeared in benhealth (issue 28, autumn 2014), the magazine for members of benenden health.