Is “Diet Resistance” a Thing?
Is “Diet Resistance” a Thing?
Steve Kamb of “Nerd Fitness” just posted a newsletter that is a nice follow up to last week’s blog “Can I Gain Weight From Eating Too Little?”1 He asked: Can people actually be diet resistant?
The short answer: No.
In 1992, a group of researchers conducted a study on “weight-resistant” individuals. These individuals reported eating less than 1200 calories per day and still could not lose weight.
The study included two groups. Group 1 comprised people who were “diet resistant”. Group 2 comprised those who reported no “diet resistance”.
The study asked: What was different about the two groups that they processed calories so differently?
The answer: Not much.
The study discovered that those who reported eating 1200 calories per day were underestimating their consumption by 47%. So, while they THOUGHT they were eating 1200 calories/day, they were ACTUALLY consuming 1800 calories or more!
Group 1 also overestimated how many calories they were burning through exercise by 51%! Instead of the 300 calories they THOUGHT they burned, they ACTUALLY burned 200!
So, what does this massive discrepancy between what people thought they consumed and what they thought they burned mean?
It means people suck at estimating!
Then there’s the metabolism excuse. “Of course I’m gaining weight! My metabolism slowed down in my 30s/40s/50s!”2
Science, however, says otherwise.
A 2021 article published by Harvard Medical School discussed the results of a study on metabolism published in Science magazine. The study comprised 6,421 individuals (64% of them female) from 29 countries. These individuals were between the ages of 8 days and 95 years. The findings showed that metabolism peaked much earlier in life than previously thought and declined much later. In fact, the study’s results “strongly suggest we may no longer be able to blame weight gain in middle age on a slowed metabolism.” 3
Another Harvard article states: “The reality is that for most people, excess weight is not all due to bad luck, thyroid trouble, or some other unexplained, uncontrollable external factor. For most of us, calories in/calories out has a strong influence on changes in weight over a lifetime.”4
So all of this points to the idea that we need to expend more calories than we consume in order to lose weight. It’s the old CICO (calories in-calories out) truth discussed in last week’s blog.
What can we do as individuals to manage a healthy weight? The Harvard article sums it up this way:
Evidence still strongly supports
- eating a healthy, balanced diet consisting primarily of whole foods in the form of fruits, vegetables, lean protein, and whole grains
- maintaining an active lifestyle with a goal of at least 150 minutes of physical activity a week, including strength training to increase or maintain lean muscle mass
- getting adequate rest, which for most individuals is seven to eight hours of sleep daily
- managing stress through mindfulness, meditation, or other relaxing activities.5
According to Steve Kamb, rather than beating ourselves up when our estimates are way off, we accept that we’re bad at estimating (because everybody is), and adjust our behaviour accordingly:
- We can learn how to actually track calories, educate ourselves on actual serving sizes for our favourite foods or meals.
- We can work on eating nutrient rich, more filling foods that have less calories, such as lean protein, fruits and vegetables. It’s quite tough to “overeat” vegetables!
- We can cut back on easily consumed liquid calories and switch to zero calorie beverages.
And even then, despite our best efforts, we should accept that we’ll still eat more than we think each day.
Not because we’re broken, dumb, or stupid.
But because we’re human.”6
(If hyperlinks don’t work, please copy and paste address into search bar)
1 https://www.nerdfitness.com/newsletter/
2 https://www.nerdfitness.com/newsletter/
4 https://www.health.harvard.edu/does-metabolism-matter-in-weight-loss
