London - Eat three square meals a day - that’s what your mother taught you and the experts have largely agreed. In the past there’s been some talk about eating “little and often” to keep blood sugar and energy levels steady, but for most people that seemed a little faddy.
But research is emerging to suggest eating little and often is healthier for us, and that we should be having as many as nine meals every day. This may help lower blood pressure and cholesterol, and even encourage weight loss.
“Splitting food intake so we eat many times a day will have metabolic benefits over and above the same food consumed in a small number of meals,” says Dr Susan Jebb, head of the Medical Research Council’s Human Nutrition Research Unit.
In one of the latest studies, scientists from Imperial College, London, compared the diets of more than 2,000 people from the UK, Japan, China and the US. While they all had the same calorie intake and food, half the participants ate fewer than six times a day, while the remainder ate more than six times.
Results show the first group had a significantly higher systolic blood pressure - the pressure that blood exerts on vessels while the heart is beating - compared with the more frequent eaters. They were also significantly heavier.
The researchers are now planning a trial involving 50 patients with high blood pressure who will eat either three or nine meals a day to assess the effects of the different regimens. As well as their blood pressure, patients will have their levels of insulin, glucose and fatty acids recorded.
The Imperial studies follow several other reports that suggest we should be scrapping the idea of sticking to breakfast, lunch and dinner. For instance, research from the University of Athens, based on more than 2,000 children aged nine to 13, found those who ate five times a day were 32.6 percent less likely to have high levels of bad cholesterol than those who ate fewer meals.
Meanwhile, eating at least four small meals a day - a “nibbling” diet, as researchers called it - sped up metabolism and lowered the risk of obesity, according to a Maastricht University study.
It’s important to note that no food is eaten between meals, which are small. In the first Imperial study, meals for those who ate six times a day averaged 300 calories - the equivalent of a small serving of chicken, rice and vegetables.
It’s not clear why eating more often has these benefits, but one theory is that frequent meals prevent a high influx of fatty acids - compounds that are released from foods and can lead to a build-up of fats in the arteries, and also contribute to high cholesterol levels. The build-up can also narrow the blood vessels, leading to high blood pressure.
Eating more frequently during the day means there are no sudden spikes of fatty acids, enabling the body to deal with the intake more effectively.
“Research suggests that levels of fatty acids in the blood remain more stable with frequent eating of smaller amounts - peaks and troughs in fatty acids have been linked to an increased risk of cardiovascular disease,” says Dr Vasant Hirani, a senior research fellow at University College London and a specialist in public health nutrition. “I now eat little and often.”
Eating more frequently may boost energy levels, suggests a study from the University Of Montana. When forest firefighters were given standard lunches or ration ‘grazing’ packs designed to be eaten over a long period of time, those who had grazing packs did 25 percent more work than the lunchbox workers.
So how is this approach different from just adding a snack between meals? The regularity of the smaller meals may be just as important as the quantity, say experts.
Recently, scientists in Israel revealed that snacking haphazardly throughout the day can lead to more weight gain compared with eating at regular times.
The team fed mice either a regular diet or allowed them to eat whenever they wanted. Both consumed the same amount of calories. After 18 weeks, the results showed that the mice who ate haphazardly gained more weight, had higher cholesterol and were less sensitive to insulin.
The team say timing of food seems more important than the composition of a meal, but are unsure why this should be.
One theory is that regular meals help our body to maintain a constant metabolism. If you eat haphazardly, the body does not know when the next meal will arrive, and so as a survival mechanism starts to store more food as fat.
While eating three square meals a day has been the norm for generations, it has no biological basis, says Professor Paul Freedman, editor of the book Food: The History Of Taste.
“It is a cultural thing,” he says. “Three meals a day came in around the 19th century, and the changes that occurred were linked to other events. Artificial light made it possible to cook and eat after dark.
“There were work changes, too. In the 19th century, a worker in Britain would start his morning with ale and bread, then bring food into the fields and have a large meal in the afternoon. He might have eaten what he called ‘dinner’ at 2pm, depending on work, season and other factors.”
Professor Freedman adds: “We became comfortable with the idea of three meals, but changes in work and lifestyles are undermining that concept. In the last century, work dictated that we ate at specific times.
“When that factory whistle blew at 5pm, it was time to go home and eat, but now we are eating later because we work longer hours.
“We are losing the idea of three meals a day thanks to grazing, because household members have different schedules, and because children might not want to eat what and when their parents are eating. Any time of day has become a time to eat.”
However, eating frequent meals is not an excuse to eat more, says Dr Susan Jebb, and it’s important that calorie intake is tightly controlled if people are going to eat as many as six or nine meals a day.
“The danger is that encouragement to ‘eat more frequently’ becomes a licence to consume too many calories and that usually involves more fat, sugar and salt, too - all of which will negate the small effects of more frequent eating,” she says.
“One strategy might be to split your main meal into two, and save dessert for a mid-meal snack.”
And another potential downside of multiple eating sessions is its effects upon teeth. “Eating more frequently increases the exposure of teeth to the enamel-dissolving acids produced when plaque bacteria digest food,” says Professor Damien Walmsley, chairman of the British Dental Association’s health and science committee.
“Sweet foods are particularly damaging to teeth and are best eaten just after savoury foods, when saliva production is increased, which helps to neutralise the acid.”
A NINE-MEAL-A-DAY MENU
8am: Boiled egg, slice of wholemeal toast with a tsp olive spread and Marmite (230 cals)
10.30am: 80g frozen berries, 125g low-fat yoghurt (99 cals)
11.30am: Two Multigrain Ryvita spread with quarter of a 170g pot guacamole (172 cals)
1pm: 300g bowl of pea and ham soup and a mini pitta (235 cals)
3pm: Small toasted teacake with two tsps butter (236 cals)
5pm: An apple and a Babybel cheese (120 cals)
7pm: Salad of rocket and baby tomatoes with tbsp of olive oil and grated Parmesan (195 cals)
8.30pm: 120g grilled salmon fillet with half a pack of coriander and lemon couscous, and peas (473 cals)
10.30pm: Mug of instant hot chocolate and a digestive biscuit (180 cals)
TOTAL: 1,940 CALORIES - Daily Mail