Tokyo 2888

Lose Weight by Public Transit?

Does public transit have one more benefit you can add to an already significant list? A new study in The BMJ finds that people who commute to work on public transit have a significantly lower BMI and less body fat than people who drive. This difference — a bit shy of a full BMI point — can’t be explained away by any confounding factors that the authors examined.

In a companion editorial, Anthony Laverty and Christopher Millett call on public health and healthcare professionals to deliver “strong and consistent messages to politicians and the public.” Leaving their car at home “will not only improve their patients’ health in the short term but also help reduce the likelihood of hazardous climate change further in the future.”

Naturally, the media obliged with headlines sure to grab readers:

Lose Weight Fast with the Transit Diet
Weight Loss Secret: Forget the Car

Does it really matter that those claims are not provably true?

Walking, biking, or using public transit is a great idea in many ways. It’s our preferred means of getting to work. But systematic review of trials and cohort studies makes it plain that it’s still just associated with better health outcomes, including less obesity.

Increased physical activity — which active commuting promotes — is the indispensable way to stay leaner. But it’s an utterly ineffective way to lose weight. Lot’s of people try this and blame themselves when it doesn’t work.

It does matter. People should not expect that leaving their car at home will solve their problem with obesity if they already have it. There’s no evidence to say that it’s an intervention that will — as those false headlines say — lead to weight loss. For that, we need stronger measures. And honestly, we need more ambitious research.

Let’s move and let’s hop on public transit are great ideas. They can probably help lots of people stay healthier — including people with obesity. But suggesting that they’ll reverse the problem for people who already have obesity is simply false.

For that, we need real, evidence-based solutions, not false promises.

“An ounce of performance is worth pounds of promises.” — Mae West

Click here for the study and here for the editorial that goes with it. Click here for more from Reuters. Click here for a recent systematic review of the health benefits of active travel.

Tokyo 2888, photograph © Tokyo Form / flickr

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