Weight Loss Diets : The Good the "Fad" and the Ugly
Updated: Mar 3
Dieting can feel like a bit of a minefield and it’s no surprise. Fad diets are fashionable and clever marketing makes them appear much sexier than the public health guidelines. Fad diets are often endorsed by a B list celebrity or rumoured to be favourite to a Hollywood star. So it’s no surprise they tend to generate more hype than Maureen and Doris do, talking about the latest public health campaign, down at the community centre. On top of this is the choice. There are so many but are they actually any good? Whilst some are plain ridiculous, others present both pros and cons but they are all ultimately successful or unsuccessful dieting strategies for the same reasons.
The most popular reason to employ a fad diet it is to lose weight. All fad, weight loss, diets tend to achieve this initially for the exact same reason. You are in a calorie deficit and without this you simply won’t lose weight. Some fad diets measure calorie intake to ensure a deficit, others restrict food groups altogether which leads to a calorie deficit indirectly. Kuchkuntla, Limketkai, Nanda, Hurt, & Mundi (2018) recently reviewed the scientific studies connected to some of the most popular fad, weight loss, diets of recent years. The table below identifies the pros and cons associated with them:
Kuchkuntla, Limketkai, Nanda, Hurt, & Mundi (2018) highlighted three key points:
1. There were more Pros than Cons identified with all the fad diets observed.
2. The Diets that were least restrictive towards food groups (i.e. Mediterranean Diet, Weight Watchers & Zone Diet) were least likely to be associated with poor compliance.
3. Weight regain always coincided with poor compliance.
This suggests that ultimately to successfully lose weight and keep it off in the long term the weight loss diet you choose needs to be sustainable for you. It needs to develop from a tactical weight loss diet into your habitual food intake. It almost doesn’t seem fair does it. You’ve been good as gold with your diet for months so surely you deserve a few months of indulgence! Unfortunately, weight-loss doesn't play by these rules.
Your body has a natural biological defence against reduction of body weight. Widespread obesity and overweight amongst the world’s population is a relatively new epidemic. So, it’s unsurprising human biological make up still prioritises a protection against starvation. A function of which most of our ancestors would have required not so long ago. This means that even after you’ve reached your target weight, you will still be required to stick to an energy intake target to maintain that weight. The longer you manage to maintain your new weight, the less your body fights against it.
The good the “fad” and the ugly…
Just like all things fashionable, some fad diets are more functional than others. Look out for the warning signs of an excessive energy deficit or lack of opportunity to consume essential nutrients. Fad diets present their own pros and cons so with this in consideration one might stand out for you personally. Regardless of the diet you employ it would be beneficial to monitor your energy balance to some extent to avoid an excessive negative energy balance. If compliance becomes an issue, consider choosing a diet that is less restrictive but ensure a dramatic change of energy balance does not occur as a result.
Studies show moderation of negative/ positive energy balance (+/- 600kcal) and regular physical activity are characteristics of people who manage to maintain a reduced weight following weight loss. So, why not keep it simple? Why not keep it flexible? It works after all.
Rosenbaum, M., Hirsch, J., Gallagher, D. A., & Leibel, R. L. (2008). Long-term persistence of adaptive thermogenesis in subjects who have maintained a reduced body weight. The American Journal of Clinical Nutrition, 88(4), 906–912.