Can Eating Too Little Prevent Weight Loss
the myth
A common myth is: “when we eat too little the body holds on to fat to stop us starving." However, research has demonstrated even in cases of the most extreme calorie restriction, subjects continue to lose weight.
The 1944 Minnesota Starvation Experiment saw subjects reaching extremely low body fat percentages while following very low calorie diets for extended time frames (1). We know that weight loss does continue to occur alongside extreme calorie restriction.
The body does make efforts to prevent weight loss by reducing non-essential activity and drastically increasing hunger. However it cannot continue to function, beat the heart, pump the lungs, walk you to work or do an exercise class without the energy to do so (2). This energy must either be coming from food or from your stored energy. If there is less food energy going into your system than required for this, you will be breaking down fat and/or other tissues to fuel your essential energy requirements.
However, while the physiological answer is that “eating too little” doesn’t prevent weight loss, the practical answer can look quite different.
the reality
A very common scenario is as follows: severe calorie restriction throughout the week does create a substantial deficit & facilitates some weight loss. But, due to severe restriction we can feel lethargic & our motivation to exercise decreases as we make subconscious efforts to conserve energy. The drop in exercise & activity may lower our calorie expenditure reducing the predicted calorie deficit somewhat, i.e we're now eating less, but also doing less!
Our hunger & willpower both reach breaking point by the weekend at which point we give up & binge through all the foods we restricted in the week. This calorie surplus is enough to offset the deficit created earlier in the week. As a result we are more or less at maintenance calorie intake overall & our weight remains stable.
The next week continues with the same cycle of guilt & restriction, followed by guilt & binging. The net result is long term weight maintenance alongside the potential muscle loss & increased body fat, all while eating very small amounts of food in the week and not feeling great.
This is a very common picture, particularly for the petite female consuming less than 1200kcal in the week & then frequently eating out at restaurants or having big nights out at the weekend.
the solution
While individual strategies may vary, it can often be sensible to increase calorie intake in the week to a more sensible figure (moderate deficit). This allows you to fuel more effect training sessions & keep active throughout the day. It also makes it more reasonable that this intake can be adhered across the weekend too (even if the food choices change some what).
By adding a little bit of what you like each day you may be able to more effectively manage cravings at the weekend. This creates a more stable sustainable deficit, more conducive with getting stronger & facilitating fat loss.
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