too much fruit?

Ok, so I know that fruits have a ton of natural sugar in them...does that affect weight loss in any way? Because I have eaten about 2 dozen fresh cherries, a handful a strawberries, a banana and a plum so far lol. Any input would be much appreciated, thanks!

Ok, so I know that fruits have a ton of natural sugar in them...does that affect weight loss in any way? Because I have eaten about 2 dozen fresh cherries, a handful a strawberries, a banana and a plum so far lol. Any input would be much appreciated, thanks!

Fructose Sets Table For Weight Gain Without Warning

ScienceDaily (Oct. 19, 2008) — Eating too much fructose can induce leptin resistance, a condition that can easily lead to becoming overweight when combined with a high-fat, high-calorie diet, according to a new study with rats.

Although previous studies have shown that being leptin resistant can lead to rapid weight gain on a high-fat, high-calorie diet, this is the first study to show that leptin resistance can develop as a result of high fructose consumption. The study also showed for the first time that leptin resistance can develop silently, that is, with little indication that it is happening.

The study, “Fructose-induced leptin resistance exacerbates weight gain in response to subsequent high-fat feeding,” was carried out by Alexandra Shapiro, Wei Mu, Carlos Roncal, Kit-Yan Cheng, Richard J. Johnson and Philip J. Scarpace, all at the University of Florida College of Medicine in Gainesville. The study appears in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, published by The American Physiological Society.

Leptin as regulator

Leptin is a hormone that plays a role in helping the body to balance food intake with energy expenditure. When leptin isn’t working -- that is, when the body no longer responds to the leptin it produces -- it’s called leptin resistance. Leptin resistance is associated with weight gain and obesity in the face of a high-fat, high-calorie diet.

Obesity has been a growing problem in the U.S. and in other parts of the world and fructose has been suspected of playing a role. Fructose is the sugar found in fruit, but it’s not the normal consumption of fruit that is the problem. Table sugar and high-fructose corn syrup are about 50% fructose and these ingredients have become increasingly common in many foods and beverages. With sugar and high-fructose corn syrup being added to many foods, people now eat much more fructose than ever before.

The University of Florida researchers hypothesized that a high-fructose diet could lead to leptin resistance, which in turn could lead to exacerbated weight gain in the face of a high-fat, high-calorie diet, a typical diet in industrialized countries. To test their hypothesis, the research team performed a study with two groups of rats. They fed both groups the same diet, with one important exception: one group consumed a lot of fructose while the other received no fructose.

Two groups similar over six months

During these six months, there were no differences in food intake, body weight, and body fat between rats on the high-fructose and the rats on the fructose-free diets. In addition, there was no difference between the two groups in the levels of leptin, glucose, cholesterol or insulin found in their blood. There was only one difference at the end of the six months: The rats on the high-fructose diet had higher levels of triglycerides in their blood.

The researchers next tested the animals to see if they were leptin resistant. They injected all the animals with leptin, to see if they would respond by eating less. Animals whose leptin response is functioning normally will lower their food intake. The researchers discovered that the rats on the high-fructose diet were leptin resistant, that is, they did not lower their food intake when given leptin. The no-fructose animals responded normally to leptin by eating less.

This first six months of the study showed that leptin resistance can develop silently. “Usually, leptin resistance is associated with obesity, but in this case, leptin resistance developed without obesity,” Shapiro said. “This was very surprising.”

Role of diet

Having seen that leptin resistance could develop silently, the researchers next wanted to find out what would happen if they switched the rats to a high-fat, high-calorie diet -- the kind many Americans eat. They found that the animals exposed to the high-fructose diet, the leptin resistant rats, ate more and gained much more weight and fat than the leptin responsive animals on the fructose-free diet. All told, this study showed that leptin resistance can:

develop by eating a lot of fructose
develop silently, that is, with very little indication it is happening
result in weight gain when paired with a high fat, calorie dense diet
Scarpace said the study suggests it is the interaction between consumption of large amounts of fructose-containing foods and eating a high-fat, high-calorie diet that produces the weight gain. “This study may explain how the global increase in fructose consumption is related to the current obesity epidemic,” Shapiro said.

How it happens

Other studies have shown that elevated triglycerides impair the transport of leptin across the blood brain barrier. The researchers hypothesize that the elevation in triglycerides produced by fructose prevented leptin from reaching the brain. If leptin does not reach the brain, the brain will not send out the signal to stop eating.

“The presence of high fructose alters the way leptin works, fooling the brain so that it ignores leptin,” Scarpace said. Consumers should be cautious about what they eat, checking labels to see how much sugar the items contain, Shapiro said.

The researchers hope to perform future studies to find out if leptin resistance can be reversed by removing or reducing the fructose content of the diet.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by American Physiological Society.
Journal Reference:

Shapiro et al. Fructose-Induced Leptin Resistance Exacerbates Weight Gain in Response to Subsequent High Fat Feeding. AJP Regulatory Integrative and Comparative Physiology, October, 2008; DOI: 10.1152/ajpregu.00195.2008
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American Physiological Society (2008, October 19). Fructose Sets Table For Weight Gain Without Warning. ScienceDaily. Retrieved July 5, 2010, from http://www.sciencedaily.com /releases/2008/10/081016074701.htm
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How too much fruit can make you fat! Thought plenty of grapes or apples will keep you healthy? Think again...

By Simone Cave
Last updated at 8:48 AM on 17th March 2010

Many of us believe that fruit can only be healthy and so make an effort to boost our intake - carrying apples in our bags, eating grapes or bananas at our desk and trying to stick to fruit salad for dessert.

But it seems some people are actually eating too much fruit, leading to health problems such as obesity, and to tooth decay.

There's no denying fruit's health benefits - it's packed with vitamins, fibre and antioxidants, which protect against disease.


Marilyn Monroe would probably have had a shock if she had eaten that fruit expecting it to be a low-calorie snack
It's considered so beneficial that the government's five-a-day guideline is a minimum recommendation for the amount of fruit and vegetables we should eat.

But while it is fine to exceed this amount if you are a healthy weight, if you are overweight or suffer from high cholesterol or diabetes, too much fruit could be trouble. It could also explain why, despite your healthy lifestyle, you're piling on the pounds.

One of the problems is people forget that fruit - like all food - contains calories. And the calories in fruit can make you just as overweight as those in chocolate, explains Dr Carel Le Roux, consultant in metabolic medicine at Imperial College London.

SO HOW SUGARY IS YOUR FAVOURITE FRUIT?

We're meant to eat five portions of fruit and vegetables a day - ideally two of fruit and three of veg. But depending on your choice, you may be consuming more fructose - or fruit sugar - than you thought.

All values are for one piece of fruit, unless specified, and the figures in brackets show the equivalent amount of sugar.


• Apricot 0.45g fructose (pinch of sugar)

• Clementine 0.5g (pinch)

• Plum 1.6g (large pinch)

• Fresh fig 2g (1/2tsp)

• Eight cherries 2.4g (1/2 tsp)

• 1 slice honeydew melon 3g (over 1/2 tsp)

• Kiwi fruit 3g (over 1/2 tsp)

• Orange 3.6g (over 1/2 tsp)

• Five strawberries 4g (1 tsp)

• Glass of orange juice 5g (1 tsp)



• Banana 5.5g (1 tsp)

• Small mango 6g (1 tsp)

• Grapefruit 7g (1 1/2 tsp)

• Handful raisins 8.7g (nearly 2tsp)

• Golden Delicious apple 11g (2tsp)

• Pear 11g (2tsp)



• Granny Smith apple 8g (11/2 tsp)

• Handful dried apple 8g (1 1/2 tsp)

• Large bunch (500g) grapes, 39g (nearly 8 tsp)

'Different people over-eat different things,' he says. 'But the people who eat fruit to excess are often weight-conscious. I've seen patients who can't understand their obesity because they eat healthily, then it turns out they are eating way too much fruit or drinking fruit smoothies all day - glugging down 300 calories in a couple of minutes.'

And it's not about lack of self-control. Fruit is packed with fructose (fruit sugar) and this doesn't make you feel full.

When we eat sugar, our body releases the hormone insulin, which tells the brain we've had enough to eat, explains dietician Ursula Arens of the British Dietetic Association.

'High insulin levels dampen the appetite, but fructose doesn't trigger this insulin response, so the brain doesn't get the message that you are full,' she says.

Essentially, when we eat fruit we bypass this internal 'stop button', which could explain why some of us can absent-mindedly nibble away at slice after slice of melon or munch through a large bunch of grapes.

Weight gain isn't the only health problem associated with too much fructose. It can increase levels of triglycerides, a type of blood fat known to be linked to heart disease.

Dr Le Roux says: 'We tell patients with high cholesterol to be careful with fruit. Too much drives up triglycerides. Diabetics should also take care, as the high fructose content can raise blood glucose levels.

Then there's the damage fruit can cause to teeth. Chewing fruit releases sugar in the mouth, where it attacks the teeth. Fruit juice or smoothies are even more of a problem, as the juicing or blending breaks down the fruit further, so more sugar is released in the mouth.

Teeth are particularly vulnerable to acidic citrus fruits, which can soften tooth enamel. Although the enamel will harden again after about 30 minutes, if you brushed your teeth immediately after drinking orange juice, you would brush away some enamel, raising the risk of dental erosion.

Dried fruit is another problem, because it's not only high in sugar but is also very sticky.

Dr Anjali Shahi, a Cheshire-based dentist, says: 'Little bits can stick to the teeth for a long time and dental cavities can result.'

She adds that raisins are as bad for the teeth as sweets. 'This is a problem for children, who are often given raisins by health-conscious mums. I've noticed a rise in dental cavities now the healthy fruit message is so strong.'

Even those who don't actually eat much fruit could be getting far more fructose than they realise - regular sugar that you add to your tea consists of 50 per cent glucose and 50 per cent fructose.

Fructose is often added to manufactured products, such as fizzy drinks, yoghurts and cereal bars in the form of glucose-fructose syrup. You can get as much as 30g of fructose from one fizzy drink.

So how much fruit is too much? Unlike salt and saturated fats, there is no recommended daily allowance for fructose. And this is unlikely to change soon.

As Ursula Arens, of the British

Dietetic Association, points out: 'Too many nutritionists would jump up and down if the public picked up the message that eating an apple wasn't good for them.'

Yet one possible guideline emerged after a recent study at Colorado University. Scientists looked at 4,500 people with no history of high blood pressure and discovered those who ate more than 74g of fructose a day increased their risk of the condition by up to 87 per cent.

Though this is the equivalent of ten apples or 30 oranges, you'd need only just over three large smoothies to top this figure (one smoothie contains around 23g of fructose).

It is worth noting, too, that bananas and some other fruits, such as strawberries, become richer in fructose as they ripen and some of the starch is converted to sugar.

The secret is to get your five a day with a mix of fruit and vegetables.

'People who are obese or have heart conditions should limit their fruit to one portion a day, along with four portions of vegetables,' says Dr Le Roux. 'You'd still have plenty of antioxidants, but you'd bring your fructose levels and calories down.'

However,most people find fruit easier to eat and it should remain a key part of a healthy diet.

As Glenys Jones, a nutritionist at the Medical Research Council of Human Nutrition, says: 'Everything in moderation. Just as you make a decision not to eat a packet of biscuits, you should think about portion control when it comes to fruit.'

She sticks to a banana and a glass of apple juice with her cereal, an orange mid-morning and an apple mid-afternoon. 'And if I get the urge to eat chocolate at night, I'll sometimes have raisins. Even so, I still limit how many raisins I eat.'

I look at it this way... I did not get fat by eating too much fruit. Period.

I also want to do this in a way that I can do for life, not just *until* I lose the weight. If I want to binge on fruit every once in awhile well, that is better than what I've binged on in the past.

lusting after my cherries eh? haha thanks so much for your advice!!!