Have you ever lost a friendship after your friend found a new love interest? Now research confirms it happens all the time. A study out of Oxford University found that on average, people shed one friend and one family member from their inner circles when they start a new romantic relationship.

An anthropologist surveyed people aged 18 to 69 online about their friends and lovers. Participants were asked to list all the people they felt they could turn to in a severe emotional or financial crisis. They were also asked how long they’d been involved in their personal relationships.

While the singletons listed an average of five people in their support network, those in relationships only had four including romantic partners. The researchers say this shows there’s a kind of isolation effect occurring when a new relationship forms

They point out there’s a downside for the new romantic partners as well. It can put a lot of pressure on because suddenly, as a mate, the individual is expected to offer the same amount of support that two people once brought to the table.

And they could regret deserting their friendships in the event of a breakup.

Do you ever feel like you need a coffee and a sweet to get through your work? Well, it turns out there’s a reason for that. The combination of caffeine and glucose can improve the efficiency of brain activity, according to a recent study that used MRI to identify the effects of these two substances.

Participants were tested after drinking a study beverage containing either caffeine, glucose or the two combined or a placebo consisting only of water.

The researchers found that the combination of the two substances improves cognitive performance in terms of sustained attention and working memory by increasing the efficiency of the areas of the brain responsible for these two functions. This supports the idea that there’s a synergy between two substances, in which each one boosts the effect of the other.

The study was published in the journal Human Psychopharmacology: Clinical and Experimental.

Here’s another reason being bilingual is a good thing. It can delay the onset of Alzheimer’s disease and its symptoms for between years. This is the surprise finding from researchers at Toronto's Rotman Research Institute at Baycrest.

In a study of more than 100 bilingual patients and 100 monolingual patients, they found that the bilinguals experienced the onset of symptoms and were diagnosed with Alzheimer’s disease between four and five years later than monolingual patients.

This confirms results from an earlier study.

What is not clear is why. It may have something to do with a unique ability in people who speak more than one language. Research has shown they have an ability to suppress irrelevant or interfering information so they can concentrate on information that is relevant.

In other words, they damp down the language they are not using and focus on the language they are using.

One of the researchers finds that bilingualism does not necessarily stop the brain from degenerating, but rather it may provide something that compensates for the brain degeneration.

And there is some evidence that speaking more than two languages provides even more of a benefit.

We know that good nutrition has a role in staving off mental decline. Now it seems there’s an even easier way to boost your short term memory: drink more water. Or at least make sure you’re drinking enough. This, according to a new study from Britain, which tested how volunteers reacted to 30 degree temparatures for four hours. Half were allowed to drink 300 millilitres of water and half were not.

Those who did not drink water found the tests more difficult to perform than those who hydrated during study, and their scores were lower. Previous work has also shown that being even just slightly dehydrated can impair attention and memory, and it is easy to get this minor degree of dehydration even in cool fall temparatures if you don’t drink water often enough. Dehydration can also reduce your mood, which in turn can affect memory.

The researchers say men need 12 to 13 cups of water and women need 9 cups. The good news is that all drinks except alcoholic one count towards that requirement. That includes beverages with caffeine. The work is published in the Journal of Clinical Nutrition.

When you're in a public restroom, do you go for the paper towels or the air dryer after you wash your hands? To get your hands cleanest, choose the towels.

A study in the Journal of Applied Microbiology put each drying method to the test and revealed that rubbing hands thoroughly dry with paper towels may give people the best chance of walking out of the restroom with germ-free mitts.

The researchers found that no matter which method you choose, you won't be rid of germs unless you dry your hands thoroughly. Germs love water. It's their ideal medium for multiplying and getting around. Putting in the time and effort to really dry hands completely will mean way fewer germs. And drying hands vigorously with a paper towel bested rubbing them dry under a blower when it came to germ levels. It seems the skin-on-skin friction created when we rub our hands under the blower somehow releases more germs that live deep in our pores.

If you want to use the blower because it’s greener, don't rub your hands. Hold your them still, palms up, and leave them there for at least 30 seconds -- but longer is even better. Whatever you do, don't give up and wipe them on your jeans or shirt sleeves. You'll just re-contaminate your hands. And don't leave them wet.

Do you have gum disease? It could be a warning sign of an increased risk of cancer. A study in Cancer Epidemiology Biomarkers and Prevention links periodontal disease with increased risk of several types of cancer in older women, even in those who never smoked.

Researchers followed more than 65,000 women, average age 68, for about eight years and found more than 7,000 cancers. Periodontal disease was tied to a 14 percent higher risk of developing any type cancer. But the greatest risk was for esophegeal cancer, which was more than three times more likely in the women who had gum disease than those who didn't.

While the risk was highest for esophageal cancer, it was also elevated for cancers of the gallbladder, breast lung and melanoma. Interestingly, it was not associated with cancers of the pancreas, liver or lower digestive tract.

Researchers speculate that gum pathogens could reach other sites through swallowed saliva, causing inflammation in other organs. Or gum disease could just be a marker for general health.

The bottom line according to the study authors: treating gum disease can be helpful in managing cancer.

If you’re trying to lose weight, here’s some advice that may be counterintuitive. There’s research showing that switching to diet pop might actually cause the opposite of the desired effect.

Researchers at the University of Texas found that drinking diet soda was associated with an increased waist circumference.

In fact, over the course of the study, people who consumed diet soft drinks experienced a 70 per cent increase in waist circumference compared to those who did not.

This doesn’t necessarily mean cause-and-effect relationship between drinking diet pop and weight gain — just that those who drink diet sodas tend to see increased waist circumference over time. The researchers believe there’s enough evidence to merit drinking something else.

One possible explanation is that some artificial sweeteners commonly found in diet soda are sweeter than sugar, and they may actually make you crave sweeter things. And some people may believe they can eat more because they are taking in fewer calories by drinking diet soda.

One of the keys to a better night’s sleep is connected to our reasons for getting out of bed in the morning. According to study from Northwestern Medicine and Rush University Medical Center Having a purpose in life makes people more likely to sleep better at night with less sleep apnea and restless leg syndrome.

The study is based on more than 800 older people aged 60 to 100 years old with an average age of 79 – more than three quarters were female. None had dementia. Those who felt their lives had meaning were 63 percent less likely to have sleep apnea and 52 percent less likely to have restless leg syndrome. They also had moderately better sleep quality.

This is the first study to show that having purpose specifically results in fewer sleep disturbances over a long period of time. The researchers say helping people cultivate purpose could be an effective drug-free strategy to improve sleep quality, particularly for Zoomers, who have more insomnia and sleep disturbances. The researchers say it can be cultivated and enhanced through mindfulness therapies and they believe that although the participants were older, the findings will likely apply to the broader public.

The paper is published in the journal Sleep Science and Practice.

We already know that there’s a connection between slowed walking and mental decline, but now a study suggests why. And it also may hold clues about easier and cheaper ways to test.

Researchers followed a group aged 70 to 79 for 14 years. Those who developed slowed walking during the follow-up also showed shrinkage of their right hippocampus, according to the study. That brain region that governs memory and "spatial orientation".

That suggests that doctors should check older patients' walking speed and watch for changes over time, since it could be an early indication of mental decline. The study authors say that typically when physicians notice a slowing gait in their patients, they refer them to physical therapy. Now they want doctors to consider the possibility of a brain pathology and refer the patient for a cognitive evaluation,"There is no cure for dementia but if it is detected early, there are treatments that can delay its progression. The findings are published in the journal Neurology.

Do you have lower back pain? Most of us can expect to experience it at some point in our lives. For many people, it’s chronic. Now a study in the Annals of Internal Medicine, finds that a yoga class designed specifically for back pain can be as safe and effective as physical therapy in easing pain.

The protocol was developed by researchers at Boston Medical Center with input from yoga teachers, doctors and physical therapists. It focuses on gentle poses, like the cat-cow,the triangle pose and child's pose. Relaxation techniques were part of the class as well. Take note: More difficult poses, like inversions, should be avoided.

After about a year, the yoga participants had about the same amount of improvement as the group that received physical therapy. The study also found that though around 70 percent of participants were taking pain medication when the study began, the number decreased to around 50 percent at the end of the first three months, for both the yoga and the physical therapy groups. Medical guidelines recommend that people with back pain should avoid pain medicines if possible.