Why You Should Run Far Away From Low Calorie Diets


In the last week, as I’m scrolling through Facebook hoping to avoid life’s responsibilities, I have come across several posts about people questioning whether low-calorie diets are a good idea.


Well, last week I wrote about cutting carbs and why carbohydrates are actually very important in your diet.  Not only do they provide a plethora of nutrients, but they also give us energy and proper neurological function.  


Well, just because a person cuts carbs in their diet, doesn’t mean they’re following a low-calorie diet.  If you’re on a low-cal diet, this is a very intentional type of diet. It’s a means to lose weight and lose it fast.  


What is classified as a low-calorie diet?


Depending on your age, gender, height, and current weight, etc., low-calorie diets can be classified as anything under 1200 calories.  


How much food does my body need to function?


That depends.  Every person is different and unfortunately, there isn’t a ‘one size fits all’ answer to this. The basic amount of calories your body needs for your vital organs to function is called your Basal Metabolic Rate (BMR).  That means, for example, that you are lying in a bed, not moving, not participating in physical activity, etc.  Your BMR is the minimum amount of food and calories you need to eat in order to keep your body alive.  


Above that is the Total Daily Energy Expenditure or TDEE.  This is the amount of energy your body needs in order to maintain life and be active.  When I’m evaluating a meal plan for a client, it’s imperative to take both the BMR and TDEE into account.  


Are low-cal diets safe?


There are quite a few studies out there on low-calorie diets, their efficacy, and their safety.  The most common times you might see a low or very low calorie diet used are in extreme cases with obese individuals with a BMI of 30 or above.  One study found that in both diabetic and non-diabetic subjects, a short-term low-calorie diet was effective for weight loss and they did not find any decrease in metabolic function (Henry et al, 1986).  Take note that this study was only conducted for 6 months.


Well, I only want to lose a few pounds to find my bikini body this summer…


Well, my response to that is: what if you could have your bikini body year round?  What if you put health so high at the top of your list that every choice you made resulted in something positive for your overall wellness?  Don’t get me wrong, it’s a lot harder than it sounds and it’ll take some serious intentionality, but it’s possible to change your overall lifestyle and maintain the body you want year round.  


What if you didn’t have to bounce around from diet to diet every year?  What if you could just work to change your habits and make nutritional choices that consistently benefited you?  


Low-calorie diets are useful for very few situations and shouldn’t be abused.  Another study found that low-calorie diets are, in fact, correlated to an increased risk in cancer (Fontana et al, 2006).  


Low-calorie diets restrict a person from receiving a healthy amount of nutrients that the body needs.  Keep in mind that your body needs certain nutrients in order to boost its metabolism which is what aids in you losing weight!  


Keep in mind that after time, your body will be so desperate for energy and calories that your weight-loss journey will likely stall because your body has transitioned into starvation mode thus holding on to every piece of fat it can in order to preserve your organs.  


I’m pregnant or breastfeeding.  Are low-calorie diets okay for me? 


No.  Now, more than ever, your body needs calories.  It needs food!   Do your growing baby a favor, whether still in utero or not, and eat!  That being said, the old adage of ‘eating for two’ IS NOT TRUE.  You only need an increase of 200-400 extra calories per day in order to grow a healthy baby.  It is not only unnecessary to consume hundreds or thousands of extra calories, but it’s unhealthy for both mom and baby and can lead to gestational diabetes, obesity in mother and child, and many other chronic illnesses.  




Instead of cutting your calories, consider changing your food choices.  Step away from fast and processed foods and introduce untouched, wholesome foods back into your diet.  The less your foods are touched between harvest and your plate, the better. Cutting your calories is detrimental not only to your metabolism and can actually significantly slow it down but studies also show that prolonged calorie restriction can actually lead to cancer.


It sounds counter-productive, but it would do your body good if you actually gave it as many calories as it needs from nutritious, whole foods for a prolonged period of time.  


I challenge you to change your food choices for 30 days instead of restricting calories.  





-Denke, Margo A. “Metabolic effects of high-protein, low-carbohydrate diets.” American Journal of Cardiology 88.1 (2001): 59-61.

-Diabetes 1986 Feb; 35(2): 155-164.https://doi.org/10.2337/diab.35.2.155

-Luigi Fontana, Samuel Klein, John O Holloszy, Long-term low-protein, low-calorie diet and endurance exercise modulate metabolic factors associated with cancer risk, The American Journal of Clinical Nutrition, Volume 84, Issue 6, December 2006, Pages 1456–1462, https://doi.org/10.1093/ajcn/84.6.1456