The Weight Loss Secret THEY Don’t Want You To Know

Throw a stone in a supermarket, pharmacy, or bookstore, and you’re almost certain to hit a product that promises to make you thinner. From diets books to Health Check seals to herbal supplements, I’d wager there’s no more persuasive marketing message in the world than “Helps You Lose Weight”.

At first blush, it’s tempting to think it’s because there’s no scientific consensus on what works. Those pushing weight loss books and products certainly want you to believe that the traditional view of weight management — that calories come in by eating, get burned by activity, and that pressing either lever will affect weight — is antiquated thinking and demonstrably wrong. Indeed, you have to accept this premise if you’re going to “need” what they have to sell.

And it’s not a hard premise to accept either. After all, this “calorie math” — wherein either eating less and keep your activity level the same (diet), or eating the same and increasing your activity level (exercise) will lead to weight loss — has been around for decades, during which we’ve continued to grow more obese as a society. We all know people who’ve tried to make it work and failed. Not to mention that it’s no damn fun to put into practice.

But anecdotes and weak correlation aside, there’s another even bigger problem: the research actually does show that neither calorie restriction nor exercise are particularly good long term weight management strategies. This is an uncomfortable reality (and huge challenge) for obesity researchers, but it’s a smoking gun for the marketers of diet products, justifying the need for a new way of looking at weight loss.

Fortunately for the marketers, there’s no consensus on an alternative, so everything is fair game. On the calories-in side of the equation, most of the difference comes from the view that certain types of calories are worse than others. Public health agencies, reflecting the traditional scientific consensus, tell us that low-fat diets aid weight loss. Fans of low-carb diets like Atkins and The Zone generally dismiss this advice, choosing to demonize carbohydrates instead. Gylcemic-index diets tend to be somewhat more measured, only demonizing simple carbohydrates while venerating complex carbs that are allegedly slower to digest.

All of these approaches have heavily-touted success stories to back them up, and most of us know people in our lives that have lost weight with each of these strategies. Such anecdotes are often persuasive, yet the comparative studies have largely failed to support the claims of any of them.

For example, a large, two year study completed in 2010 that assigned 800+ overweight adults to four diets with differing levels of fat, carbohydrates and proteins, found that all four had comparable levels of weight loss — and that all participants began to regain weight after 12 months. A smaller study published in 2005 found a similar lack of differentiation between four specific diets — Atkins, Ornish, Weight Watchers, and Zone. And a 2003 systematic review found that weight loss from low-carb diets was “principally associated with decreased caloric intake and increased diet duration but not with reduced carbohydrate content.”

So does this vindicate the “old science” of calorie math? Not exactly. First, as mentioned above, while all diets provide short term weight loss, they start to wane in efficacy in the medium term and none are particularly good at long term weight loss. And second, the results on the calories-out side of the equation are also pretty dismal. A large study completed in 2009 found that while some weight loss can be expected with exercise, there were diminishing returns as exercise levels increased due to “compensatory mechanisms that attenuate weight loss.”

There is no time to explain. Let me sum up.

So the secret to weight loss is calorie math, which isn’t particularly useful for weight loss. Thanks science. Is it any wonder marketers are having a field day?

Fortunately, as skeptics we have a few more tools in our belt which — while not carrying the predictive weight of scientific consensus — can still help us make a plausible read of the situation that’s consistent with what we do know. I’m going to suggest two are relevant here.

The first is the dynamics of placebo responses. As we’ve seen with placebo treatments from homeopathy to reiki, simply doing something can have an effect. I suspect this is why most diet and exercise programs have positive results in the short term — the intervention itself causes behavioural changes that result in lower caloric intake even when that’s not the primary focus of the diet program. As time wears on, the intervention normalizes, the effect wears off, and the gains begin. In other words, it’s not the diet itself but the attention to eating that really matters. The diet is just a placebo that triggers it.

The second is the dynamics of our cognitive machinery. The cognitive sciences have demonstrated time and again that much of our decision making is automatic, and that it often takes a fair amount of cognitive effort just to recognize that, much less counteract it. Caloric regulation is so intrinsic to our survival that we’re hardly aware there’s even a regulation mechanism at all. Worse for the dieter, it was designed under conditions of caloric irregularity and often scarcity, so errs on the side of caloric accumulation in times of plenty, which is every day for most Canadians.

If the above is true — and again, I’m basing this on general skeptical principles in the absence of specific evidence, so reader beware — then weight loss is essentially a cognitive problem. The calorie math works, but our body is designed to automatically compensate for caloric reductions or higher exertion levels. In the short term we can override that automatic process through deliberate decisions about how many calories to consume and expend (i.e. diet and exercise), which may be further aided by the intervention effect of eating attentively. But keeping that weight off will require a dieter both to become permanently aware of their caloric regulation (i.e. notice themselves automatically eating more to compensate for the deliberate calorie loss), and to stop themselves from doing it.

What that means for dieters is that any tool that forces them to be aware of what they put in their mouths and its relationship to weight could have a significant impact on long term weight loss. I’d suggest that explicit weight loss goal-setting, diet diaries to track consumption and expenditure, and regular weigh-ins are probably at the top of that list. Diet books, supplements, and wonder-foods don’t even rank.

And that’s the real secret THEY don’t want you to know — losing weight may not be fun or easy, but you don’t need to take out your wallet to do it.


Photo courtesy of dno167b via Flickr under Creative Commons

9 Responses to “The Weight Loss Secret THEY Don’t Want You To Know”

  1. Alex T says:

    The diet is just a placebo that triggers it [attention to eating].

    I don’t buy it, I wonder if you have that flipped around.

    The diet and the exercise are key, at least from a mere physiological perspective. However without the attention to eating, the equation is likely to slip. The diet is not a placebo, it’s a vital component in the equation that also happens to lead to secondary features such as attention.

    I think there are a lot more items that you’re skipping over and jumping far too fast to the same sort of quasi-mystical mind-over-matter conclusions that the quacks do. Maintenance of lost weight is hard because the psychological reinforcements are gone. We shift from making progress to stability which is a lot less rewarding. We see the progress and find it easier to justify excess. The support network of appreciative oohs and aahs from friends dries up once we stabalize. And with all that, we lose our attention and we get off the path.

    You said it yourself, there were diminishing returns as exercise levels increased due to “compensatory mechanisms that attenuate weight loss.”

    • Erik Davis says:

      I think you’ve taken that line out of context. My point there wasn’t that there’s no mechanism for weight loss — the calorie math works — but that even diets that purport not to care about the calorie math end up reducing calories because of the intervention effect of eating attentively. It was really just an explanation for why all diets seem to show similar results regardless of their purported mechanism of action.

      The remainder of the article takes up the issue of long term weight loss and why diets and exercise don’t work, suggesting that it’s not that the calorie math breaks down, but that we compensate for the reduction automatically, so I don’t disagree with anything you’ve said.

  2. ted says:

    Good article, i like the simplicity to explain something that doctors and trainers sometimes fail to explain to people ho don’t know so much about how the human body works.
    Finally weight loss is about knowing yourself and being aware of what you eat and regular exercise, there’s no long term tricks is just making an action a habit, that’s what we fail at first.
    Sorry my english, great site, keep doing the good work.

  3. CC says:

    Here’s an interesting study on attentive eating.

    In short, if you pay attention to how much you eat (in this study, counting how many times you swallowed) you’re satisfied faster and thus eat less.

    • Erik Davis says:

      Yeah, I suspect this is on the right path. Which is not to say that there aren’t likely diet-based approaches to satiety management as well — many dietitians will talk about the role of protein, fibre, and food density in making people feel fuller faster — just that cognition-enhancing approaches can be another useful tool, esp. in the long term.

      For what it’s worth, Judith Beck — a leading CBT practitioner and trainer, and daughter of Aaron Beck, who founded Cognitive Therapy — has a diet book out based on cognitive principles. I’ve only skimmed it, but it looks pretty interesting.

  4. Ampov says:

    I completely agree with everything you said above and I will support it with an example from personal experience. I must admit I already tried many of the diets you mentioned above and the result is just transient.

    It is true that you will reach your primary goal- losing pounds but what happens several months after you finish your diet? You regain your weight. There is no diet that will guarantee you that you will never regain weight.

    My point is that weight-loss is connected to healthy eating and consciousness. You don`t have to starve yourself to lose weight. You just have to follow some of the eating principles you establish. No book or guide is needed for that, just be determined and once you are conscious what you eat you will start losing your weight.

  5. Larry says:

    Diet and exercise don’t work when looking at large groups because the average dieter/exerciser are not good at it. However, if you look at subgroups and individuals you can find extremely good athletes and dieters who have mastered the equation, without drugs. It requries efforts far beyond what the average person is motivated to do and keep doing though.

  6. Luke says:

    @Larry – Completely agree. We conducted a study at my University but results were completely distorted because of this. Only a select few actually train and diet properly


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  • Erik Davis

    Erik is a technology professional based in Toronto, focused on the intersection of the internet and the traditional media and telecommunications sectors. A reluctant blogger, he was inspired by the great work Skeptic North has done to combat misinformation and shoddy science reporting in the Canadian media, and in the public at large. Erik has a particular interest in critical reasoning, and in understanding why there’s so little of it in the public discourse. You can follow Erik's occasional 140 character musings @erikjdavis