In the latest issue of Cancer Research Update, AICR’s biweekly email newsletter on the science of cancer prevention, treatment and survival, we asked cancer researchers and educators to answer one, simple question:
What do we know today that we didn’t know just 10 years ago?
Their answers might surprise you – they surprised us. Although epidemiologists, clinicians, basic researchers and health professionals differ on what they believe to be the most important achievement in the past ten years, they agreed on one thing: It’s never been clearer that diet, physical activity and a healthy weight all play an important protective role.
This finding from a study published today is not exactly shocking, but it does suggest that flipping off one of those touching holiday movies every day can help prevent the seemingly inevitable weight gain every year.
Published in the Archives of Internal Medicine, this new study also strengthens AICR’s expert report findings. The report found that sedentary living and watching a lot of TV was linked to weight gain and obesity, which is the big story in cancer lately. AICR estimates found that excess body fat leads to about 100,000 cancers every year in the United States.
Basically, this was a small study that first counted how much TV 36 adults watched. All the participants were overweight or obese. After three weeks, they randomly split the participants into two groups: one group didn’t change their TV habits and the other cut their TV viewing time in half (this was enforced by an electronic lock-out system).
After another three weeks, the researchers found that those who watched less TV burned 119 more calories per day during the three-week lock-out period than the observation period. In comparison, the control group burned 95 fewer calories per day during this three-week period compared to the observation period. Participants were wearing armbands that measured physical activity.
About 100 calories per day is the amount researchers estimate we need to either lose or burn in order to avoid weight gain.
Of course, this was a small study, participants were all overweight and they reported a minimum of 3 hours of daily TV watching per day but still, doing something instead of watching TV – or even while watching TV — is logically one way to avoid weight gain or even lose weight.
If you want to take a quiz to see if you are active enough for good health, click here.
…. the study was not a randomized clinical trial of soy consumption. That is, rather than randomly assigning breast-cancer survivors to consume or not consume various amounts of soy, then following those participants to see whether they developed recurrent tumors, the study looked retrospectively at women’s self-determined soy-eating habits.
So far so good.
But then came this next bit:
The randomized clinical trial is the gold standard upon which medical practice is determined, and the only kind of trial that gives scientists confidence that other variables are not confounding their results.
Yeah, that’s … not always true. Not when you’re studying something as complex as the human diet, and a disease that can take many years to develop, like cancer.
When it comes to studying diet, lifestyle and cancer prevention, the randomized clinical trial (RCT) is one tool investigators use, but it can’t – and shouldn’t – be considered the be-all and end-all, the “gold standard” in all situations.
After the jump: The difference between studying cancer treatment and studying cancer prevention.