How do you avoid overeating?

Since the 1970s portion sizes have increased dramatically amongst children and adults. According to psychologists children rely on adults to show them how much to eat so we decided to see if, when doubling portion sizes, children know when their satiety signals are saying stop.

"They ate 73% more on the second day"

We are all born with an efficient system that tells us when we are hungry and when we are full. However, very early in life we are taught to override these signals. When children are presented with a large portion they will eat all of it in spite of feeling full. If children overeat consistently they are going to be overweight.

We took a class full of children and gave them an identical meal on two consecutive days. The difference was that on the first day we gave them the government recommended allowance and on the second day we doubled it.

Did the children know when to stop? Not quite. They ate 73% more on the second day than they did on the previous one. A 2000 study showed that three year olds still heard their satiety signals and stopped eating when they were full. Five year olds, on the other hand, finished their plates no matter what the portion size.

Eating habits are cultivated early on in life- if we are not careful we may be the first generation to outlive our children because of obesity so don’t overfeed your child.

How do you get your kids to eat their veg?

38% of adults will only eat 10 foods. So how do you get your children to eat something that even adults won’t try?

"peer groups are the biggest influence on young children"

Cognitive research shows that peer groups are the biggest influence on young children - if the boy next door is eating it, chances are your child will want a piece of the action.

We brought in four older child-actors to see if their influence could make our vegetable haters change their eating habits. The plan was that by lunchtime our undercover agents would have worked their magic and Isaac, a self-confessed broccoli hater, would be a reformed, vegetable-eating character.

Did it work?

Isaac’s friend Luke, who had earlier claimed to hate peas, witnessed his new found friends eating their veg and attacked his with fervour. Isaac, with a little encouragement, not only tried his broccoli but ate the entire portion without fuss. Now he’s tried it once there’s a chance he will try it again so a week later we film Isaac and his family enjoying a meal at home. Although Isaac still doesn’t like the tomato his mum encourages him to try he needs no persuasion to eat his broccoli.

So, peer groups have a larger influence on children than their teachers or parents so bring in the backup and remember- if you can get your child to try something once there’s a chance they will try it again and again until they like it.

Does restricting food make children want it more?

Research shows that by making foods unavailable they become more attractive. To test this we took a classroom of four and five year olds and examined their reaction to restricted treats over the week.

First, we had to find two foods that all the children were nonplussed about- we tested them with a range of dried fruit snacks and mangos and raisins were equally indifferent in the children’s preferences. Then the fun began. Every day, at snack time, we put the two bowls of snacks side by side and told the children that on the first whistle they had 15 minutes of unrestricted access to the mango. At the second whistle they had only five minutes of snack time to eat the raisins.

"there was a stampede to reach the forbidden fruit"

We watched the children day by day as the mango fell out of favour and the kids began cravin’ raisins. To begin with the children snacked voraciously on the mango but were more excited when it was raisin time. By the end of the week there was a stampede to reach the forbidden fruit, and the mango was looking less and less attractive.

The same kids who were indifferent to both snacks at the beginning of the week couldn’t get enough of the raisins by the end.

So, by restricting snacks you may have the adverse effect of making your children desire them even more and even encourage them to hide their snacking habits.

Can vegetables help you resist infection?

Within the colon there are over 500 bacterial species, making up about 95% of cells in the body. In effect, we are living, breathing, bacteria-carrying monsters!

Good bacteria in the gut break down carbohydrates to create 10 % of our daily energy. They also help the body fight infection and disease by combating the effects of the bad bacteria.

"The prebiotic group managed to increase their good bacteria numbers by 133 million"

We took 8 hard-working cowboys, and divided them into two groups. Half of them were put on a diet of probiotics - cultures containing good bacteria found in foods such as yoghurt. The other half we put on a prebiotic diet - substances found in certain vegetables such as leeks and bananas, which make the pre-existing good bacteria in the gut healthier.

Then we got down to the dirty work. Their poo was examined daily to measure the change in bacteria. If the good bacteria are fed well they should multiply in number and make the ranchers healthier.

The cowboys’ poo showed that the prebiotic group managed to increase their good bacteria numbers by 133 million, small in bacteria terms, but an encouraging effect. The probiotic group saw little change over the week, but over a longer period there’s evidence that they can make a difference.

It seems from our investigation the best thing you can do for your bacterial health is treat your good bacteria to a prebiotic meal. The best vegetables to feed good bacteria are artichokes, garlic, leeks and onions.

Can eating like an ape improve your health?

he prominence of diseases connected to high cholesterol and blood pressure in the world’s population raises the issue of whether our current western diet is a major factor in the development of cardiovascular illness, hypertension, stroke and diabetes.

Are we paying the price for eating processed foods?

"our group’s total cholesterol fell by 23%"

We took ten volunteers back in time to take a leaf out of the book of our ancestors in order to investigate what impact our short, sharp, shock would have on reducing the risk of fatal illnesses.

At the end of the period we tested the biological markers cholesterol and hypertension as the measures of our success. In just twelve days our group’s total cholesterol fell by 23% and we also saw a sharp decrease in sodium levels.

So, what does this show? That simply by introducing changes into our diet, by aping our ancestors, we can dramatically improve our health.

Can water help fill you up? - Soup Diet

There’s a common dieting myth that if you drink a glass of water before you eat you will feel fuller for longer.

But is there any truth in this? We took it upon ourselves to put the water theory up against the latest idea in the science of dieting.

The new buzzword in dieting is satiety - it’s less about reducing your calorie intake and more about eating foods that will keep you satiated for longer.

To illustrate our study we conducted at Nottingham University we took two teams with a love for classic American automobiles and sent them on a road trip through the lonely Nevada desert to see which group would give in to their hunger pangs first.

Both teams were given an identical meal of chicken and vegetables with a glass of water. The only difference was that one team drank the water before they ate, and the other had the water blended with the meal to make a soup.

Then we sat back and waited for the hunger signals to kick in.

In the original study the group who ate the chicken and vegetable soup were satiated for 60 minutes more when compared to the group who drank the water before the chicken and vegetable meal.

"activating our satiety signals can reduce our hunger by up to a quarter"

But why? When we drink a glass of water with our meal our stomach is able to sieve the water from the solids passing quickly from our intestines into the stomach. However, when we combine the water and food in a soup this sieving is prevented and ensures that the water and the nutrients from the food stay together, homogenised, thus entering the intestine at the same time.

Because of the increased volume of the water and solid combined the food stays in our stomach for longer, activating our satiety signals and delaying emptying, which, according to the scientists, can reduce our hunger by up to a quarter.

Which type of food is the most filling?

Many of us think that the best way to fill our stomachs is with a large amount of carbs. But is this the best way to keep us from snacking throughout the day?

We decided to find out. Research shows that eight out of nine subjects ate less after a protein-rich meal than after a protein-poor one.

To illustrate this we recruited three volunteers used to working long shifts and snacking on the job to see if we could give them a meal that would set them up for the long day ahead. We fed each of our recruits a pasta meal - one high in fat, one high in protein and one high in carbohydrates. Then we detained them at Her Majesty’s pleasure just to make sure they couldn’t give in to temptation.

Four hours later we let them loose and carefully observed as they tucked in to a well earned pizza.

"subjects ate less after a protein-rich meal"

The inmate who ate the smallest amount during lunch was the one who had had the protein-rich meal.

So, if you don’t want your hunger getting you in trouble, try a meal high in protein to keep hunger locked away for longer.

Does portion size affect how much we eat?

n 2005 a study in America revealed that the size of a container can powerfully and unknowingly increase how much food a person consumes.

To illustrate this we reconstructed the study to see if a larger container led to an increase in consumption.

We took 150 movie goers and gave half of them large size buckets of popcorn (120g) and the other half extra large ones twice the size (240g). As an added test we even gave half of the audience stale popcorn. Then we waited until the film was over to see just how much they left behind.

"45% more popcorn was eaten"

The results showed that 45% more popcorn was eaten when it was given in extra large containers.

What does this illustrate? That when we supersize snacks our perception of what is an ‘acceptable’ amount to consume increases. So, if you don’t want to eat more than you need, steer clear of supersizing.

The larger the portion the more you will eat.

Does Detox work?

Despite the high profile of detox diets, very little research exists to prove whether it has any measurable value. In this study, we put the diet to the test, finding out if following a strict detox plan can really reduce the body’s toxic load and enhance the efficiency of our body’s innate systems.

"relying on a detox isn’t the solution"

We took ten party animals to a country cottage retreat for ten days to see if a detox diet could recharge their internal batteries. The group was split into two and half the girls were put on a balanced diet, including red meat, alcohol, coffee and tea, pasta, bread, chocolate and crisps (in moderation), with the remainder following a strict vice-free diet.

Can a short, sharp shock really change the levels of toxicity in your body in just a week?

After testing the kidney and liver functions and measuring the antioxidant and aluminium levels in their blood we found there were no differences between the groups.

Which just goes to show, in a binge and purge culture relying on a detox isn’t the solution. Your body has its own way of regulating toxins and a week of suffering won’t change that so you are better off sticking to a balanced diet all the time.

Can spinach save your eyesight?

We’ve all heard that carrots help you see in the dark. But can spinach help prevent sight loss?

In the UK, over 25% of the over 60s have some degree of visual loss because of Age-Related Macular Degeneration (AMD).

AMD occurs in the centre part of the retina called the macula. It can cause blindness in the centre of the eye, with peripheral vision only remaining.

Part of the retina’s protection is a pigment, lutein, which absorbs UV blue light, the most damaging wavelength of sunlight. Lutein is also thought to be an antioxidant which helps maintain the health of the eye. The pigment itself can only come from diet, and one very good source for this is spinach.

"over 25% of the over 60s have visual loss"

We gave a group of people who have early signs of the disease a six month spinach rich diet - half a bag of fresh spinach a day. We examined their eyesight at the start and end of the diet to see if the spinach helped slow or even repair the damage that old age had wrought on their eyes.

One participant, Joan, who has noticed a decline in her eyesight over the last few years, attacked the spinach diet with fervour and tests show that not only has her condition not degenerated at all over the last three months but that she has even shown some improvement in eye sensitivity.

Can berries improve your memory?

he effects of cognitive changes are usually not noticed until we approach our 70s and beyond. As we age our brain faces increasing damage from inflammation and oxidation leading to a substantial decline in cognitive ability.

"fruit and veg could reverse the effects of ageing"

Given the dramatic rate in which the older population is increasing (the number of those 85 and over is expected to double to more than 1.8 million by 2028) it is crucial we investigate ways to minimise vulnerability of the brain from ageing.

One approach on how to do this might be found in nutrition. Research suggests that antioxidants found in fruit and vegetables might be the key to both stopping and reversing the deleterious effects of ageing on neuronal communication.

And scientists have also discovered that anthocyanins, the colourful antioxidants found in berries, can help protect against diabetes, heart disease, cancer and a range of other age-related diseases.

We took two groups of fun-loving OAPS and tested improvements in their memory over four months of a berry supplemented diet. Over the four months the groups undertook online cognition tests and learnt a new dance.

We asked one group of bowls-mad OAPS to eat a diet high in strawberries for three months. Then we went across the pond and asked their American equivalents to do the same with blueberries. We then tested improvements in their memory over the four months of their berry supplemented diet.

Was there a difference? Well, only some of our group noticed any changes in their memory but larger studies have shown marked improvements. So, if they were to continue to eat a cupful of berries every day for the rest of their lives they might notice a marked improvement in their cognition. If there’s a chance it might work, then there’s no harm in trying.

The scientist who devised this study was Dr James Joseph from Tufts University, Boston, USA.

Is snacking better for your performance?

What is the best way to consume the right amount of calories but not slow down after eating them? New research suggests that how you eat can prove vital in how long you keep going.

In Montana, Oregon, summers are hot and humid. Amongst 22 million acres of forest wild fires spread, well, like wildfire. For this reason it is essential that the fire fighters controlling the flames are energised and alert at all times.

"those who grazed on FSRs completed 25% more work"

The test was conducted by Brent Ruby, University of Montana, Missoula. He fed teams of forest fire-fighters on either their standard packed lunches which were eaten all at once, or on specially made First Strike Rations (FSRs), designed to be eaten on the go over a long period of time.

He found that those who grazed throughout the day on FSRs completed 25% more work on their 10-12 hour shifts than those on packed lunches.

People in physically demanding jobs need a consistent supply of glucose and other nutrients. If this supply comes all at once blood rushes to the gut to help digest the food. This temporarily reduces the blood supply to the rest of the body, which means the muscles can't work as efficiently. Snacks need less energy to digest so less blood rushes to the gut, which allows it to be used by working muscles and should mean the snackers are able to work harder.

The consultant on the study was Brent Ruby, professor at the Department of Health and Human Performance Exercise Science Program at the University of Montana, Missoula.

Does drinking two litres of water a day improve your skin?

It’s common knowledge that drinking two litres of water a day will keep us properly hydrated. But is this true, or another myth?

We enlisted the help of beauty conscious twins Susie and Alice to see if we could solve the mystery. We asked one of them, Susie, to give up their two litre daily bottled water addiction to measure how their body, and more importantly, beauty was affected. They got their fluids from tea, coffee and soft drinks instead.

"we lose approximately 2 litres of water each day"

Five days later we conducted some rigorous tests to see what had happened to the water-starved twin. Was her skin in a state of stress? Not really, no.

In fact, both Susie's moisture and elasticity showed no major change after five days. Why? Well, a reasonably inactive adult (like most of us who work in offices) loses approximately two litres of water each day through breath, sweat, urine, and faeces, which is where the myth that we need those two litres a day may have originated.

All drinks we have during a day, apart from alcohol, count towards making up this amount - including tea and coffee - and more than a third of our water needs comes from our food.