Do you believe any of the following?
- Exercising over time produces cumulative weight loss based on calories in versus calories out
- Setting realistic weight loss goals is important to keep people motivated
- Losing weight gradually (1-2 lbs per week) creates more sustainable weight loss
If so, you are not alone!
The problem is these commonly held beliefs are actually myths that persist despite refuting evidence.
I would encourage you to read an interesting article “Myths, Presumptions, and Facts about Obesity” from the prestigious New England Journal of Medicine, January 31, 2013.
Using more rigorous studies, the article cites evidence of actual observations, not assumptions.
- The body actually compensates for sustained calorie inputs or outputs; it’s not calories-in / calories-out for weight loss
For example, whereas the 3500-kcal rule predicts that a person who increases daily energy expenditure by 100 kcal by walking 1 mile (1.6 km) per day will lose more than 50 lb (22.7 kg) over a period of 5 years, the true weight loss is only about 10 lb (4.5 kg)…
- “Realistic” weight loss goals do not help
Indeed, several studies have shown that more ambitious goals are sometimes associated with better weight-loss outcomes…
Furthermore, two studies showed that interventions designed to improve weight-loss outcomes by altering unrealistic goals resulted in more realistic weight-loss expectations but did not improve outcomes.
- Losing weight fast is more effective in the long-run than losing weight gradually
Within weight-loss trials, more rapid and greater initial weight loss has been associated with lower body weight at the end of long-term follow-up.
There are even more results in this analysis, including myth busting surrounding the number of calories expended during sexual intercourse! (I won’t give you the answer here!)
So why do these myths continue?
Net is that we don’t force scientific method and evidence-based rigor into our beliefs.
We are influenced by:
- repeated media exposure to claims
- cognitive dissonance – we don’t like to hear contradictory evidence to ideas that are important to us
- confirmation bias – we only seek data supporting claims we have already accepted as true
- ability to be swayed by persuasive (yet fallacious) arguments
Topics related to weight loss and obesity aren’t the only areas where these factors influence us.
Read the article and be careful what you believe in!