I stumbled upon a large portion of this documentary from the BBC, “10 Things You Need to Know About Losing Weight” a few nights ago. Medical journalist Michael Mosley investigates what science has actually proven to work for weight loss (sounds familiar). Much of what they talked about has already been covered in this one book about weight loss that’s really good. It’s by these two incredibly handsome young men…
The most exciting part, in my opinion, starts at about 8:30 into this video and continues into this video where Debbie gets her metabolic rate tested and finds that her metabolism is spot-on average and she can no longer blame her weight problem on a slow metabolism. Then they have her keep a food diary for nine days, first by video at the end of the day and then by journaling throughout the day. At the same time, they use the doubly-labelled water method to calculate the amount of calories she takes in and expends. When comparing her video and journal food diaries to the doubly-labelled water calculations, they find Debbie failed to report 60 and 43 percent of her calories, respectively.
When using memory to recall foods eaten over the day she either forgot or under-reported almost 2,000 of the roughly 3,000 calories she ate. She’s not alone. Children, the elderly, the obese and athletes have all under-reported intake in studies. (Hill)
Doubly Labelled Water – Quickly
The doubly labelled water method actually only measures energy expenditure, from which a scientist can surmise energy intake by comparing any body weight changes that may have occurred. Basically, in the case above it goes like this:
Debbie says she ate 2,000 calories.
Her energy expenditure as measure by DLW is 3,000.
Debbie didn’t lose weight, so she must actually be consuming 3,000 calories.
The cool thing about DLW is it accounts for any metabolic advantage there might be for any food, since it’s the total energy expenditure that’s being measured. Any rise in metabolism is accounted for. She’s simply under-reporting.
So, What Did We Learn Today Class?
First, we learned the BBC puts out some cool stuff.
Second, we learned that many people from all demographics underestimate the amount of food they eat. From this, we can assume that if a person isn’t losing weight, the first action is to control the food intake, either by strictly weighing and measuring foods or finding a method that controls portions indirectly, like eating a low carb or ketogenic diet, or using some sort of intermittent fasting program. Honestly, I don’t like to screw around so I would strictly weigh and measure food, at least near the beginning. After a while maybe start to back off being so strict unless or until the results stop coming.
Third, we learned that you either have a serious interest in losing weight or are really bored, because you made it this far 🙂