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'Tis the season for recovering from all that holiday cheer — and making that perennial New Year's resolution that just never seems to succeed.

There's a reason that the ever-popular losing weight resolution doesn't work, says Leigh Vanderloo, exercise scientist at ParticipACTION. In fact, she says it's a terrible resolution to make.

"If you try to tie your confidence or how much you view your self-worth or your self-esteem to solely the number on the scale, I think you're truly doing yourself a disservice," Vanderloo told CBC News.

Losing weight used to be viewed as a relatively simple "energy in, energy out" equation, she said, so people thought "all you had to do was move more and eat less and that would solve the problem."

"I think you're truly doing yourself a disservice - ParticipACTION's Leigh Vanderloo, about basing self-esteem on one's weight

But the factors that make someone overweight or obese are much more complex than that — and some, such as genetics, are not necessarily under their control, Vanderloo said.

In addition, a goal of "losing weight" is extremely broad. A much more effective approach, she said, is to examine why you want to drop a few pounds, and then make a goal involving a specific behaviour change to address that.

For example, if someone wants to lose weight because they want to feel more confident, setting an activity goal makes sense, she said, as increased confidence and ability to deal with stress are both known benefits of physical activity.

But Vanderloo cautions against equating "physical activity" with "going to the gym" — because that's another New Year's resolution that people often abandon by March.

If exercising is a chore, it means you haven't found the right activity yet, she said. Achievable goals include walking a certain distance a couple of times a week, trying a new activity like skating, swimming or fencing — or even pledging to get up from your desk and walk over to talk to people instead of sending them emails at work.

And if you want to improve your eating habits, Vanderloo says, make those goals specific too, such as drinking more water or eating more fruits and vegetables.

If weight loss comes as a result of those lifestyle changes, that's great, she says. But by not making it the end goal in and of itself, you're not setting yourself up for failure.

Weight watching for your dog

While you're considering your own New Year's resolutions, you might also take a look at your dog's midriff. Does your pooch have a pouch?

The culprit may have been all of those doggie treats. Researchers in Italy found most are packed with sugar, and "undefined ingredients." They wrote about their findings in the BMJ Vet edition.

Dog treats are used to encourage good behaviour, so they have to have an appealing taste and are often high in calories. (Dora Zett/Shutterstock )

Kate Shoveller, an animal nutritionist at the University of Guelph, understands why.

"Treats are predominantly used for training, so they have to be highly appealing. I'm not surprised to see sugar in there."

In the Italian study, researchers found that owners overfed their dogs with treats that come in a variety of forms, including biscuits, meat strips, and chewable sticks — at calorie levels that often exceeded the daily recommended energy needs of our canine companions.

"Treats are being misused by the consumer," says Shoveller.

An overfed dog often becomes overweight. In Canada, "obesity is somewhere in the range of 40 per cent in dogs and cats," she says.

"[It's] pretty akin to [the] human population."

For the record, Shoveller has a dog, a miniature dachshund called "Heart." And because she cares for her pet's heart, Shoveller says the only treat she gives her are dental sticks.

In the Italian study, the authors say labelling on dog treats should be clearer, and include more information on the ingredients and feeding instructions, especially for smaller dogs.

Shoveller offers advice for dog owners as they ring in the New Year with their furry friends.

"Think about something non-nutritive," she says. "They like spending time with us. The greatest gift you can give your dog is spending more time with them."

Retracted! 2017's biggest scientific mistakes

Retraction Watch counted 1,044 retractions in scientific publications in 2017. (Yury Zap/Shutterstock)

Oops, never mind.

That would be a recurring headline if the news media reported on mistakes in science with the same intensity that we report so-called "breakthroughs."

And this year there were some big "never minds," according to Ivan Oransky, science writer and co-founder of Retraction Watch, a blog that monitors retractions from scientific publications. The 2017 tally: 1,044 retractions, which is down slightly from last year. But Oransky says overall, the retraction rate is rising.

"There's no question that retractions have gone up. They're going up faster than the rate of papers being published."

Number one on Oranksy's top 10 retractions of 2017 is a record-breaking single day retraction of 107 papers, all from the same journal: Tumor Biology. An investigation revealed that the peer reviews on all of the papers had been faked.

Remember the headlines about fish larvae eating plastic? The paper published in Science back in June 2016 received widespread media coverage. Almost immediately, other scientists noticed problems with the data.

Science retracted the paper in April after Uppsala University in Sweden conducted an investigation and concluded that its researchers were "guilty of research misconduct." Some of the experiments were never done, which meant that the results reported were "fabricated."

CBC's Quirks and Quarks reported on the original story and have since updated with a notice about the retraction.

The most high-profile Canadian retraction came from the University of British Columbia after data irregularities were spotted in a paper linking an ingredient in vaccines to autism in mice. The problems surfaced after the study appeared in the Journal of Inorganic Biochemistry. Independent scientists reported that some of the figures appeared to have been altered.

"There was a screw-up, there's no question about that. - Professor Chris Shaw, University of British Columbia

Professor Chris Shaw, the paper's author, told CBC News he couldn't explain what went wrong.

"We don't know why, we don't know how … but there was a screw-up, there's no question about that."

Oransky gave another UBC professor high marks for doing the right thing and voluntarily correcting an honest mistake more than 15 years after the research was first published.

Professor Chris Orvig studies medicinal inorganic chemistry to develop cancer therapy. His original paper in 2002 described a particular compound that binds to radioactive metals. More than a decade later, one of his PhD students was attempting to use the chemical for a new project and discovered the compound was much smaller and less effective than they first thought.

His student said, "Boss, we have a problem," Orvig told CBC News. "After a little bit of head scratching, I sent an email to the editor of the journal."

The publisher of Inorganic Chemistry retracted the first paper and published the corrected version in August.

Oranksy and his team have set up a database listing 16,000 retractions dating back to the 1970s. They intend to link the database to the scientific publishing system so that a red flag will appear on any retracted research before scientists cite it in their studies.

"The whole point is to cut down on waste in science," Oransky said. "Science is too important and scientific dollars are too precious to be wasting time on work that's been shown to be fraudulent or wrong."

Lif e-saving Canadian invention turned 50 in 2017

When you reach for the headache pills on New Year's Day and automatically push on that child-resistant lid before turning it, you might want to marvel at this made-in-Canada ingenuity.

The child-resistant pill container was developed by Dr. Henri Breault, a pediatrician in Windsor, Ont., 50 years ago. (Jorge Salcedo/Shutterstock )

The "palm 'n turn" child resistant container turned 50 years old in 2017. The life-saving invention was developed by a Windsor, Ont., doctor who was frustrated after treating hundreds of kids who had been poisoned after swallowing pills.

Back in the early 1960s, Dr. Henri Breault decided it was time to do something.

"At three o'clock in the morning he came home and said 'I've had it. I'm tired of pumping children's stomachs,'" his wife Monica Breault said in a 1997 interview.

Dr. Breault raised $1,500 and offered it as prize money for anyone who could design a childproof pill bottle. He received 200 responses, and chose the "palm 'n turn" design created by local plastics engineer Peter Hedgewick, who patented it in 1966.

Then Breault tested the lids scientifically, asking local pharmacies to dispense pills in the child-resistant containers and systematically studying the results. His findings were dramatic — 91 per cent fewer poisonings.

In the early 1970s, Ontario made the caps mandatory and many jurisdictions around the world have followed.

Dr. Henri Breault, pictured in a file photo, saw many cases of children poisoned by swallowing pills and wanted to put a stop to it. (Canadian Medical Hall of Fame)

"The child-resistant closure is Canada's gift to injury prevention," University of Manitoba pediatrics professor Milton Tenenbein wrote in the BMJ's Injury Prevention.

"It's an injury prevention success story," Tenenbein told CBC News, adding that the lid does more than just make it hard to open the container — it also acts as a warning.

"The message it sends is that what's in this bottle is not safe, which works a lot better than a printed warning label."

But it only works if people remember to put the cap back on.

"People can get complacent and not re-engage the lid," Tenenbein said.

In a 2008 report on child injury prevention, the World Health Organization warned that no container is perfect, noting that studies have shown that up to 20 per cent of children under age two might be able to open it.

"Child-resistant closures should therefore never take the place of good supervision," the report said.

With today's potent opioids and dangerous consumer products, including laundry pods and liquid nicotine for e-cigarettes, Tenenbein said it's time for a new call out to engineers for improved child-resistant packaging.

But the old palm 'n turn lid is still a popular design used all over the world. For making it happen half a century ago, Breault was awarded a place in the Canadian Medical Hall of Fame. Peter Hedgewick, who created the clever mechanism for Beault, was inducted into the Canadian Manufacturing Hall of Fame.