Theory vs. Practice in Weight Loss and Why All Diets Work if They Can Achieve One Thing

Posted by

The most commonly forgotten aspect of nutrition is the fact that our caloric needs depend on our body mass. The heavier we are, the more calories we need to maintain this weight. Instead of speaking in terms of short term caloric surpluses or deficits, we should realize that our body weight tends towards equilibrium, it tends to stabilize: if you consume more calories than you spend your body mass will grow until your body’s caloric needs match your caloric intake and then it will stop growing. Likewise, if you spend more calories than you consume, your body mass will decrease until your energy needs become as low as your energy intake, and then your weight will stop decreasing.

No matter how many calories you consume every day, your weight will eventually stabilize. (the exception would be extremely low intake levels, but we can ignore them now)

However, what level will your weight stabilize at, depends on how many calories you consume. The more calories you consume the higher the equilibrium level at which your weight will stabilize. In fact, your current weight is probably at an equilibrium level that is determined by your average caloric intake. Let’s see an example – the following chart shows the relationship between caloric intake level and equilibrium weight for a 35 year old male, 180 cm tall and with light physical activity levels.

So, if you are a 35 year old man, who is lightly active and is 180 cm tall – and you weigh 90 kilos – then your average calorie intake is probably around 2551 calories per day.

Now let’s see – what is just one requirement any diet needs to accomplish in order to help you achieve permanent weight loss? Well it’s simple, it just needs to permanently lower your caloric intake, so that you consume the amount of calories that will lead you to a new equilibrium lower than your current one. It is the ONLY requirement any diet needs to achieve in order to be successful in the long term.

Let’s get back to our example: let’s say you weigh 90 kilos, but you think your ideal weight is 75 kilos. What should you do? Of course, the only thing you need to do is switch from your current caloric intake level of 2551 calories per day, to a new permanent caloric intake level of 2344 calories per day, and over long term, your weight will eventually approach this new equilibrium of 75 kilos. That’s all. In other words, you need to permanently cut your caloric intake for the difference between these two equilibriums – in this case, it’s 207 calories difference. So just by consistently consuming 207 calories less than you used to, eventually you’ll find yourself at the new equilibrium weight. And then in order to maintain new equilibrium, you need to continue with this lower calorie intake level. If you go back to your old intake level, so will your weight go back to old equilibrium.

There’s one little caveat here: the difference between your current intake and the intake that would lead you to your desired weight is more important than amounts of calories at these levels themselves. This is because values themselves are obtained via calculators or formulas that calculate energy needs given parameters such as height, weight, gender and activity level. These calculators and formulas vary among themselves and are not always accurate. But they usually have more agreement when it comes to the difference in caloric intake that you need to make in order to shift your weight equilibrium a certain number of kilos up or down. So, in our example here by consuming 207 calories less, you shift your weight equilibrium 15 kilos down. From this we could make a very rough estimate that for each 5 kilos of weight difference that you want to create over a long term, you need to decrease (or increase, in case you want to gain weight) your daily calorie intake level by approximately 70 calories.

You want to permanently lose 10 kilos? Just shift to an eating plan that contains 140 calories less than your current way of eating and stick to it forever that’s it.

Now let’s explore why theory and practice when it comes to weight loss can be very different. As I said before, for a weight loss diet to be successful in long term, it just needs to permanently lower your caloric intake – now how shall it be done… it’s completely irrelevant, and it can be accomplished in ANY way. As long as you are consuming less calories over long term than you used to, you’re on a good track – when it comes to weight loss.

For this reason, many diets can be successful as long as people stick to them. But almost all diets fail, not because they don’t work – but because of mentality that treats diets as a short term intervention, after which you return to your old ways. This is very wrong. The only diet that can be truly successful is one that aims for a permanent change of eating habits, which include adopting permanently lower caloric intake levels.

In practice this shift towards lower caloric intake can be accomplished in many ways and it does not necessarily need to include calorie counting. In fact many successful diets accomplish lowering caloric intake indirectly, without requiring you to count calories. For example simply switching to healthier food choices (which are typically less calorie dense) and avoiding junk food, without any quantitative restriction and without any deprivation, will typically lower your average caloric intake and therefore, cause weight loss.

Popular diets usually work (I mean, at least until people quit them and yo-yo all the way up back to old weight) through skipping whole food groups. This is unhealthy and usually unneeded, and they usually have some sort of pseudoscientific theory to support such avoidance of certain food groups (for example paleo dieters believe that we haven’t evolved to digest grains and legumes) – but the diets still work because they cause you to skip a good bunch of food, which causes you to simply consume less calories. It’s not that they work because the theory behind them is sound – they simply work because they trick you into consuming less calories. In fact it would be quite difficult to consume the same amount of calories as you used to while skipping a good bunch of food groups. For this reason, you simply consume less calories, and therefore lose weight.

Different types of popular diets are, for the most part, simply different ways of tricking you into consuming less calories.

However, here we should underline that tricks are not necessarily bad. If they work and help, they can be good. They are definitely preferable alternative to meticulous and tiring calorie counting. They only become bad, when they are based on falsehood (for example the claim that we can’t properly digest grains, and that therefore they should be avoided) and when their long term application becomes unsustainable. And, unfortunately, most diets based on skipping multiple food groups are both based on false beliefs about these groups being unhealthy AND they are also unsustainable, because in a long term they become very boring, you feel deprived, you might even develop nutritional deficiencies and eventually you get back to your old ways of eating… The diet fails. So these types of tricks are usually working just in short term, that is, until you get sick of them (literally or figuratively) and give up.

It is also a big problem if diets are intentionally misleading – namely the authors of diets may be well aware of the fact that their diets work simply because they restricts your calories, but nevertheless they invent pseudoscientific mumbo jumbo to justify the restrictions that they arbitrarily made and to make it seem as if the diet is not all about restricting your calorie intake.

The most honest and true to theory approach to dieting is the calorie counting. However it is also the most mentally demanding and time consuming. For this reason, what I recommend instead is open tricks. That is, the tricks that openly tell you they are tricks, without any deception. You can also think of your own tricks, that is – ways of achieving reduced caloric intake, without necessarily having to count calories.

Here are some of my suggestions:

a) for example, if you have a habit of drinking a glass of soft drink or fruit juice with your lunch or dinner – you can drink a glass of water or mineral water instead. One 250 ml glass of soft drinks has around 100 calories. By just skipping it, with everything else in your diet remaining unchanged – you could lose around 7 kilos in the long term.

b) Eating fruits instead of cake – typically you could save around 200 calories – which could lead to up to 14 kilos weight loss in the long term. (if you had habit to eat cake every day…)

c) Simply reducing the amount of food that you put on your plate by around 10-20% during the main meals.

d) Eating a bit less bread with main meals…

e) Eating more vegetables – not only is it healthy, but it is also bulky, leaving less space for other more caloric stuff in your stomach.

Those are just some ideas… but the main thing is that achieving sustainable weight loss is simple, and relatively easy – but only with the right approach. You must accept that you need to permanently change your ways of eating in a way that will permanently lower your average daily caloric intake. How you make this change – it’s up to you. As long as your caloric intake is adequately lowered, you’re on the right track from weight loss perspective.

Of course, when you make such permanent shift in your eating habits, you should do your best to make sure that your new way of eating is not only calorically appropriate, but also healthy and sustainable. For this reason, before making such a shift, it would be advisable to make a good plan first, you can also consult with your doctor or dietician.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s