Should link between dementia and artificial sweeteners be taken with a pinch of salt?

How people capability for forgetfulness and lies may have impacted on research tying stroke and dementia to diet drinks

They were supposed to be the healthy alternative to their sugar-rich siblings. But now lovers of diet colas and other low-calorie beverages have been hit by news that they are able to radically undermine those credentials: a counterintuitive study indicating a link to stroke and dementia.

The study in the periodical Stroke may cause a rethink among those worried about obesity, diabetes or a possible early heart attack from sugar-rich drinkings who have been considering making a change. It comes to the alarming conclusion that people polishing off one can a day of artificially sweetened drink are nearly three times as likely to have a stroke or develop dementia.

Its a shocking conclusion. But the first reason to pause is that the study seen no such risk in individuals who drank standard sugary lemonades and colas.

There is little previous proof with regard to dementia, which is why the researchers were looking at it, but the link between sugar and stroke is very well known. Too much sugar raises the risk of obesity, diabetes, heart attack and stroke. Its altogether a bad thing, which is why the World Health Organisation is telling us all to cut down. So “whats going on” in this study?

The evidence it analyses is pulled from the well-respected Framingham Heart Study a cohort of more than 5,000 people in Massachusetts, US, whose diets and lifestyles have been monitored for virtually 50 years, with the main objective of finding out more about heart disease. Along the style, researchers have looked at other health outcomes.

What they are up against is people capacity for forgetfulness and lies. This is the case with every study into the food we eat except for those rare ones, almost impossible to do today, which have in effect imprisoned their topics and controlled every sip and mouthful they took.Researchers understand this and to continue efforts to take account of it, but it is difficult.

There are several possible other reasons why an increased stroke hazard was associated with diet drinkings and not sugary beverages. One is what is called reverse causality. People who come to realise that they are ill and have a high risk of a stroke then switch their behaviour by choosing diet beverages long after sugary beverages have helped cause the problem.

When it came to dementia, the link with diet drinks that researchers saw disappeared once they took some elements of the health of the people in such studies into account. When the researchers accounted for other risk factors for Alzheimers, such as danger genes, diabetes, heart disease, cholesterol levels and weight, this important association was lost, suggesting that these beverages are not the whole story, said Dr Rosa Sancho, head of research at Alzheimers Research UK.

The researchers point to it themselves: We are unable to determine whether artificially sweetened soft drink intake increased health risks of incident dementia through diabetes mellitus or whether people with diabetes mellitus were simply more likely to ingest diet liquors, they write. But they call for more research and others will support them in that.

Artificial sweeteners have been viewed with mistrust by a lot of consumers for many years and not entirely deservedly. They are not natural, in the way that sugar is natural, being grown from beet or cane. Some of the hatred comes from those who worry about ingesting man-made chemicals. But while some artificial flavourings have been shown to carry health risks, surveys have failed to find similar problems with artificial sweeteners.

Aspartame has been extremely controversial since its approval for use by several European countries in the 1980 s, says NHS Choices. In 1996, a study linked it to a rise in brain tumors. However, such studies had very little scientific basis and later analyzes showed that aspartame was in fact safe to devour, says the NHS.

Large analyzes have also been carried out to look at whether the sweetener increased cancer risks, and devoted it a clean bill of health. The European Food Safety Authority said in 2013 it was safe even for pregnant women and children, except for anyone with a rare genetic condition called phenylketonuria.

Dumping aspartame from its low calorie bestseller did not give PepsiCo the halo consequence it hoped. In 2015, it announced it was taking the sweetener some people love to abhor out of Diet Pepsi and replacing it with sucralose. A years later, when it became clear Coca Cola would not follow suit and that fans favor their beverage the way it used to be, it did a U-turn and put aspartame back in.

There have been huge efforts to develop artificial sweeteners that will savor as good as sugar and be acceptable to the doubters. Stevia, a plant extract, is marketed as a natural sweetener to the increasingly sceptical health-conscious.

Now it is not just beverages. Public Health England is putting pressure on food companies to cut 20% of sugar from their products by 2020. That will probably mean smaller chocolate bars, where artificial sweeteners only wont deliver the same savour. But they will be part of the answer in other foods.

Sweeteners such as sucralose, which is 650 hours sweeter than sugar, have long been in breakfast cereals and salad dressings, while saccharin is in store-bought cakes, despite a scare over bladder cancer which caused the Canadian government to ban it as an additive in 1977. It lifted the ban in 2014. The security debate will go on, but artificial sweeteners are likely to play a bigger part in our diet as the squeezing on sugar ramps up.

There are those, however, who guess artificial sweeteners will never be the answer to obesity and the diseases that follow in its wake. The problem, in their view, is our sweet tooth and the answer is to reduce our liking for sweetness. So they want to see the gradual reduced to the amount of sugar in our beverages and our food and snacks without it.

It worked with salt, tells Cash, the campaign for action on salt and health, which did much to bring down the salt levels in our food without our noticing it. The same is still possible for sugar. But not if artificial substitutes are used to keep our food and drinkings savor just as sweet as they did before.

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