Calorie Restriction: How Low Is Too Low?
We all know someone who always seems to be on a diet but never actually seems to lose any weight or we may be that person ourselves. Is it because there’s something inherently wrong with us, or could it actually be our approach to dieting that’s slowing us down?
It’s easy to get swept up in the desperation and anticipation of weight loss, but severe long-term calorie restriction may actually be inhibiting your ability to lose weight and keep it off.
Reducing calories too low can have some serious adverse health effects. If maintained for long periods, severe calorie restriction may disrupt various hormone levels (e.g. leptin and ghrelin, the hormones responsible for satiety and hunger), compromise immunity and gut health, reduce bone density, increase the risk of disordered eating, and negatively impact psychological health. Once affected, many of these consequences will be difficult to normalise or may not even be reversible.
Further, prolonged periods of low-calorie intake may likely result in a slower metabolism, making it even harder to lose weight and keep it off. This means the next time around you’ll need to reduce your calories even further to drop weight - perpetuating the cycle of adverse health effects.
The general rule of thumb is to avoid decreasing intake below 30 calories per kilogram of lean body mass, at least for women. This means an 80kg woman with 56kg of lean body mass should avoid reducing calories below 1680 cals/day (56 kg x 30 cal) to avoid the negative effects of dieting.
So, the next time your personal trainer tries to put you on a 1200 calorie per day diet - run!
If you’re struggling with weight loss or are experiencing the adverse effects of restricting calories too low, consider booking an appointment with me. Together, we can explore the factors contributing to your weight and create a treatment plan tailored specifically to you.
References
Leibel, R. L., Rosenbaum, M., & Hirsch, J. (1995). Changes in energy expenditure resulting from altered body weight. The New England journal of medicine, 332(10), 621–628. https://doi.org/10.1056/NEJM199503093321001
Mountjoy, M., Sundgot-Borgen, J., Burke, L., Carter, S., Constantini, N., Lebrun, C., Meyer, N., Sherman, R., Steffen, K., Budgett, R., & Ljungqvist, A. (2014). The IOC consensus statement: beyond the Female Athlete Triad--Relative Energy Deficiency in Sport (RED-S). British journal of sports medicine, 48(7), 491–497. https://doi.org/10.1136/bjsports-2014-093502
