Blue light from smartphones may speed blindness

Dear parents, if you want your children to have proper sleep, read this carefully. Joining a growing list of studies that tell parents to shun devices at bed-time, researchers say that children who use devices and decide what time they go to sleep, achieve less sleep and feel more sleepier the following day than their peers.

The study of children in this age-group (aged 11 to 13 years), published in the New Zealand Medical Journal, found most (72 per cent) of the 163 students interviewed by University of Otago researchers achieved recommended guidelines of an average 9 to 11 hours sleep nightly over one week.

"But that also means that almost one in four students did not achieve sleep within these guidelines, which highlights an area for improvement," said study researcher Kate Ford.

However, consistent with previous research in 15 to 17-year-old New Zealanders, the study results show less sleep on the nights where devices are used in the hour before bed.

According to the researchers, students who used devices before going to sleep were also more likely to report that they felt sleepy the following morning. Watching television before bed had no significant effect on sleep length.

There were also some interesting observations over the weekends where students went to bed later but woke later achieving similar sleep length to the school days, the researchers said.

A small group of students (six per cent) who reported less than seven hours of sleep, including a small number reporting not sleeping at all, according to the study,

Therefore, while the average across the week of 72 per cent of students reporting adequate sleep is reassuring, it is far from the goal of every child achieving sleep within the recommended guidelines," Ford said.

Dr Paul Kelly, head of the Sleep Health Service at Canterbury District Health Board, supervised the study and explained that the foundations for good health are based on proper nutrition, regular exercise and good sleep quality.

Sleep quality is often overlooked as a contributory factor to poor health.

"The study findings suggest the need for parental guidance around bedtimings and moderation of the use and availability of electronic devices before bed," Kelly said.

"Respect and protect your sleep, as good daytime functioning is reliant on adequate sleep," Kelly added.

Washington, Feb 12: People who are optimistic may contribute to the health of their partners, staving off the risk factors leading to Alzheimer's disease, dementia and cognitive decline as they grow old together, according to a study.

The research, published in the Journal of Personality, followed nearly 4,500 heterosexual couples from the US Health and Retirement Study for up to eight years.

The researchers found a potential link between being married to an optimistic person and preventing the onset of cognitive decline, due to a healthier environment at home.

"We spend a lot of time with our partners.They might encourage us to exercise, eat healthier or remind us to take our medicine," said William Chopik, an assistant professor at the Michigan State University in the US.

"When your partner is optimistic and healthy, it can translate to similar outcomes in your own life. You actually do experience a rosier future by living longer and staving off cognitive illnesses," Chopik said.

An optimistic partner may encourage eating healthy foods, or working out together to develop healthier lifestyles, the researchers said.

For example, if a person quits smoking or starts exercising, their partner is close to following suit, they said.

"We found that when you look at the risk factors for what predicts things like Alzheimer's disease or dementia, a lot of them are things like living a healthy lifestyle," Chopik said.

"Maintaining a healthy weight and physical activity are large predictors.There are some physiological markers as well. It looks like people who are married to optimists tend to score better on all of those metrics," he said.

The researchers said there is a sense where optimists lead by example, and their partners follow their lead.

They also suggest that when couples recall shared experiences together, richer details from the memories emerge.

Chopik noted while there is a heritable component to optimism, there is some evidence to suggest that it's a trainable quality.

"There are studies that show people have the power to change their personalities, as long as they engage in things that make them change," Chopik said.

"Part of it is wanting to change. There are also intervention programs that suggest you can build up optimism," he added.

Drinking coffee may help reduce the risk of certain digestive disorders, including gallstone disease and pancreatitis, a new study has suggested.

The study from the Institute for Scientific Information on Coffee (ISIC) also highlighted other beneficial effects that coffee consumption may have on the process of digestion, including supporting gut microflora and promoting gut motility.

"Data indicates benefits against common digestive complaints such as constipation, as well as a potential reduction in the risk of more serious conditions like chronic liver diseases," said study author Carlo La Vecchia from the University of Milan in Italy.

Gallstone disease is a common digestive disorder, caused by the accumulation of gallstones in the gallbladder or bile duct, which affects approximately 10-15 per cent of the adult population.

While the mechanism by which coffee may protect against gallstone disease is not yet known, it has been observed that the risk for the condition declines with increasing daily consumption of coffee, the researchers said.

Caffeine is thought to play a role in these associations, as the same effect is not observed with decaffeinated coffee.

A common question among consumers and focus area for research is whether coffee is associated with heartburn or gastro-oesophageal reflux disease (GORD).

While a small number of studies have suggested an association between coffee drinking and GORD, the majority of studies reviewed suggest that coffee is not a major trigger of these conditions.

The report also reviewed a growing area of health and nutrition research, namely: the effect of coffee on the gut microflora (microorganism populations).

Recent studies suggest that populations of the beneficial gut bacteria Bifidobacterium spp, increase after drinking coffee.

The findings showed the dietary fibre and polyphenols found in coffee, support the healthy growth of microflora populations.

Additional research findings highlighted that coffee consumption is thought to stimulate digestion by encouraging the release of gastric acid, bile and pancreatic secretions.

Coffee is one of the most widely researched components of the diet, and its effect on digestion remains a growing area of research, the researchers noted.