The apparent ineffectiveness of "conventional diets" for weight loss was somewhat lost in the excitement of the recent intermittent LC study. Well, maybe not lost entirely ... there's always lots of "see, counting calories is useless" to go around. But it struck me, yet again, that part of the problem with such traditional weight loss diets is that they are simply too high in calories to produce significant losses.
Harvie's group has done a number of studies (I hope to discuss some when I get time and if I can get the full text of some) in pre-to-post menopausal age women with a focus on breast cancer risk. Her group's "standard diet" seems to be a 1500 cal/day diet. In the study presented at the San Antonio conference, the control group followed a 1500 cal/day Mediterranean style diet, and lost a piddly 4 pounds over 4 months. See? They don't work!! Perhaps the reason why they don't work, however, is because that is simply not a weight loss level of calories for most women. Now, this is a tough pill for many of us to swallow, but swallow it we must or we'll tear our hair out wondering over our metabolic derangements and hormonal dysfunction (or is that metabolic dysfunction and hormonal derangements ... or does it matter? ...).
I did the math previously, but comparing the results for the 1500 cal/day group to that of the 2-day-per-week 650 cal/day group, the numbers work out surprisingly consistent for the 4 month timeframe. Obviously the assumptions of all losses being fat, and 3500 cal/pound fat are generalizations, but:
4lbs * 3500 cal/lb)÷(4 mo * 30.5 d/mo) ≈ 115 cal/day deficit.This means that in energy balance, these women eat 1615 cal/day.
Restricted 2 days @ 650 cal/day = 965 cal deficit:2 d/wk * 17 wk * 965 cal/d ÷ 3500 cal/lb = 9.37 lbs
Which just so happens to be about what the intermittent restricted group lost. Now realize, these women are likely overweight/obese (that wasn't stated for this study, but Harvie's other work has been with overweight/obese women, weight loss and reduction of breast cancer risk). So even with some variation in intake and such, you have these women essentially weight stable (hopefully!) at a higher-than-desirable weight eating not all that much. Interestingly enough, however, they appear to be eating about that proverbial 100 cal/day extra. Had they continued to eat at the 1500 cal/day level, they would likely have lost 12 pounds in a year. Nothing earth shattering, but many DO get overweight gaining 10 lbs or so in a year. That the restricted group lost as much as it did, pretty much confirms that these women really weren't "overeating" that much to begin with.
If you want rapid weight loss through traditional calorie counting you need to cut calories drastically. This intermittent dieting strategy looks promising so long as one doesn't compensate on other days. Even 1500 cal/day allows for a lot of food, even bad foods, depending on the strategy of types of foods, number of meals, etc.
I keep going back to the graphic from this post (unfortunately unable to find original source) showing that the average American woman in the 70's was eating around 1500 cal/day. Whether that's ultimately an accurate value, it does seem to mesh with anecdotal reports and studies such as this one.
In any case, the much maligned Calories In - Calories Out paradigm offers us much actionable information after all. This intermittent approach offers something a little different. Not tremendous losses, but more than plodding along on a "moderate" weight loss diet. I would also think they are less likely to rebound than had they lost the same weight doing 650 cal/day for a few weeks. Another lesson is that, contrary to what we're often told, 650 cal/day every now and then is not some dangerous or unhealthy practice.
Perhaps one of the things we women who are overweight need to accept, is that it's not so much slow and steady wins the race, but that it's going to be rather slow. I also do believe that the apparently more rapid losses with LC are fluid balances, which does not negate their value, but explains the plateauing out once those have reached their limits. Lastly, caloric restriction (intentional or not) only gets you so far so fast. This argues heavily towards SOME exercise as part of any weight loss plan unless there's some compelling reason not to (disability, injury, etc.).