Tuesday, September 24, 2013

Why sweeteners may INCREASE your sugar craving: They tickle the taste buds, but can't fool the brain into producing the pleasure response

More perverse results from dieting

Choosing diet drinks and artificial sweeteners instead of high-calorie treats may increase your craving for sugar, a study has found.

It is because sugar subsitutes tickle the tastebuds, but can’t fool the brain.

The pleasure we get from sweet treats is the result of a chemical called dopamine, which is released in the brain when sugar is consumed and is linked to a feeling of reward.

Artificial sweeteners and other low-calorie options do not cause the same reaction, leaving dieters with their craving – and making them far more likely to binge on sugar later on.

‘[Our discovery] implies that humans frequently ingesting low-calorie sweet products in a state of hunger may be more likely to 'relapse' and choose high-calorie alternatives in the future,’ said Professor Ivan de Araujo, who led the study at Yale University’s School of Medicine.

Rather than starve yourself of sugar, he said, it is better to consume very small amounts, tricking the brain into producing a pleasure response.

The steady release of dopamine will prevent cravings from building up.

Professor de Araujo added: ‘The results suggest that a “happy medium” could be a solution, combining sweeteners with minimal amounts of sugar so that energy metabolism doesn’t drop, while caloric intake is kept to a minimum.’

Scientists suggest the findings may explain why obesity levels have rocketed despite the widespread introduction of diet drinks and snacks.

Professor Ivan de Araujo said: “The consumption of high-calorie beverages is a major contributor to weight gain and obesity, even after the introduction of artificial sweeteners to the market.

'We believe that the discovery is important because it shows how physiological states may impact on our choices between sugars and sweeteners.

'Specifically, it implies that humans frequently ingesting low-calorie sweet products in a state of hunger or exhaustion may be more likely to ‘relapse’ and choose high calorie alternatives in the future.

'The results suggest that a ‘happy medium’ could be a solution; combining sweeteners with minimal amounts of sugar so that energy metabolism doesn’t drop, while caloric intake is kept to a minimum.”

The research was performed in mice, using a combination of behavioural testing involving sweeteners and sugars, whilst measuring chemical responses in brain circuits for reward.

Professor de Araujo said: 'According to the data, when we apply substances that interfere with a critical step of the ‘sugar-to-energy pathway’, the interest of the animals in consuming artificial sweetener decreases significantly, along with important reductions in brain dopamine levels.

'This is verified by the fact that when hungry mice - who thus have low sugar levels - are given a choice between artificial sweeteners and sugars, they are more likely to completely switch their preferences towards sugars even if the artificial sweetener is much sweeter than the sugar solution.'

Further research is planned to identify the associated receptors and pathways in the brain after the study established dopamine cells were critical in sugar or sweetener choice.


Statins increase risk of cataracts, study finds

This is just a correlational study but it fits with many findings of ill-effects from statin use

They have been heralded as the new wonder drug and are used by millions to fight heart disease, but statins could increase the risk of cataracts, a new study has found.

Those taking the low-cost medication could be 27 per cent more likely to develop the condition, which leads to cloudy lenses, the researchers discovered.

Older people are particularly vulnerable as they make up the majority of statin users and cataract patients, the Daily Mail reported.

The medical records of more than 14,000 people, covering a period of more than eight years, were examined by researchers in the US.

Half of the patients had used statins for at least three months and the other half had never taken the drug.

Those who took statins had a 27 per cent increased risk of developing cataracts, which require surgery to prevent blindness, even when other factor such as high blood pressure were accounted for.

The researchers believe that one explanation could be that cholesterol is necessary to maintain healthy cells in the eye and the transparency of the lens.

The authors of the study, published in journal JAMA Ophthalmology, concluded: “The risk for cataract is increased among statin users as compared with non-users. The risk-benefit ratio of statin use, specifically for primary prevention, should be carefully weighed, and further studies are warranted.”

Statins are one of the most widely prescribed drugs in the UK, taken by more than eight million Britons.

They are currently prescribed to patients with at least a 20 per cent risk of having a heart attack or stroke within ten years.

A team from Oxford University concluded that the benefits of statins outweigh the side effects after they found they cut by at least a third the risk of heart attacks, strokes and operations to unblock arteries.

All patients in the trials, which involved 175,000 people, had a positive reaction to the drug and even healthy people given statins had lower overall death rates than those who were given a placebo.

The findings have even led to calls for statins to be prescribed to everyone over the age of 50, but the latest research casts doubt on the recommendation.

Earlier research on the link between the drugs and cataracts has provided mixed results.

Around one in three people over 65 develop cataracts, and 341,000 operations were carried out last year on the NHS.

As well as cataracts, statins have been linked to an increased risk of type 2 diabetes, constipation, diarrhoea, headaches, loss of appetite and loss of sensation or pain in the nerve endings of the hands and feet.

The Medicines and Healthcare Regulatory Products Agency has warned about the risk of sleep disturbances, memory loss, sexual dysfunction, depression and certain lung diseases.


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