The changing of the calendar is often a time for reflection - to think about the year that was and speculate on the year yet to be.
But perhaps the end of the year could be better used to discard luggage we do not want to carry forward into the future.
In the world of science, there are arguably many ideas which should die. They are either outdated or inaccurate or, in some cases, deadly wrong.
One of the books I read this year was dedicated to this very notion.
Titled This Idea Must Die, it consists of the views of 175 leading thinkers from around the world on topics as diverse as The Carbon Footprint to Left Brain/Right Brain to The Universe Began in a State of Extremely Low Entropy.
Its central thesis could be summed up by saying the pursuit of faulty ideas can lead to more harm than good.
Along the same lines, Nature published an article this month entitled Myths that will not die.
Their argument is certain commonly held beliefs or myths are damaging to scientific progress and should be abandoned. Collectively, both scientists and the general population often hold onto myths because they "sound right" even though the factual evidence would suggest they aren't.
For example, a common myth we see is "Antioxidants are good and free radicals are bad."
This shows up in television advertising for any number of products - from health foods to fitness routines.
But it is a flawed argument in many ways.
It originated in 1945 when Denham Harman's wife suggested he read an article entitled Tomorrow You May Be Younger in the Ladies' Home Journal.
This sparked an interest in aging and lead to the hypothesis that ageing might be caused by the presence of free radicals in the body.
For the most part, free radicals are naturally occurring molecules which accumulate as by-products of metabolism but he assumed they could also lead to cellular damage.
Other scientists rallied around the idea and this lead to the development of the corollary that antioxidants could fight free radicals which would promote human health and long life.
There is no question that antioxidants are able to oxidize or reduce free radicals and mitigate their damage, but the question was whether or not this was beneficial to human health.
By the early 1990s, many people were taking supplements of the antioxidants vitamin C, vitamin E, and beta-carotene in order to prevent free radicals and possibly cancer.
Yet, at the same time, studies were appearing in the scientific literature arguing regular doses of antioxidants could cause more harm than good.
Beginning in 1982, three large-scale clinical trials tested the effects of supplemental beta-carotene on the risk for chronic diseases such as cancer.
Each trial concluded beta-carotene had little or no effect on free radical formation.
The surprising result, though, was beta-carotene not only didn't provide protection against lung cancer in participants who smoked, but it actually increased the risk.
Indeed, after following the participants for a number of years, two of the trials quite unexpectedly found a higher risk for lung cancer amongst the group taking beta-carotene compared to the placebo group.
Rather than inhibiting free radical formation, antioxidants appear to interfere with natural biological processes and in doing so led to the generation of disease.
Building on this work, in the early 2000s, scientists used genetic manipulation to generate mice which over-produced free radicals.
Much to their surprise, the mice lived as long as their normal relatives and, even more surprisingly, mice engineered to over-produce antioxidants.
Various studies since have led to a significant debate in the scientific literature about the efficacy of antioxidants and the role of free radicals in aging.
The generally held belief among researchers working on aging is now that free radicals are a normal part of the body's response to stress.
They play a role in a variety of metabolic pathways. Yes, they can cause cellular damage but not to the level previously thought.
Indeed, the whole issue has brought new focus to research on aging and the role that molecular damage plays.
It is more likely the interplay of the whole metabolism and the eventual failure of processes rather than molecular species which lay at the core of aging.
Unfortunately, the antioxidant paradigm has fueled a $3 billion dollar per year supplement industry which feeds upon the antioxidant message.
It is difficult for scientists to put the genie back in the bottle.
The idea that antioxidants can prevent cancer and aging "sounds right."
It gives people a target to fight and in the meantime generates significant revenue. It is a myth whose time has come.
Perhaps at the end of 2015, we should toss it out and start thinking about better ways to take care of the whole biological system.
