Flexible dieting: A term you may have heard before but probably thought sounded too good to be true, especially when you're constantly bombarded by the latest fad diet that will supposedly help you burn off fat faster than people click out of a long article (please don't go!). I'm here to tell you that flexible dieting is not too good to be true and is actually one of the best and most efficient methods of losing weight for the majority of the population.
First things first, we need to know what ISN'T flexible dieting. Any diet that has less of a focus on total caloric intake, but has a heavier focus on other variables instead, is not a considered a flexible diet. This can be things like Keto, which focuses primarily on causing ketogenesis, low carb which focuses on reducing carb intake, and other similar diets.
These diets may include some flexibility, but are overall much more restrictive when it comes to food choice. While there's no precise foods prescribed for you to eat on most of these diets, there's usually a frame work in place that restricts your food choices. Thus, these types of diets do not fall into the "flexible dieting" category.
So what is Flexible Dieting? Flexible dieting is a style of dieting in which no foods are “off limits” and that focuses on total calorie and protein intake instead. Calories are tracked to control body weight, while protein is tracked to support lean mass retention to maximize fat loss (or build muscle in the case of a bulk). Beyond this, nothing else has to be tracked or strictly controlled. Unlike most other diets, no foods or food categories are off limits as long as you can eat them and still be within your calorie and protein recommendations. Pizza? Cake? How about tacos? All perfectly acceptable. This allows great freedom and avoids the added stress of having to worry about those scary carbs or off limit food categories.
Flexible dieting is one of the most effective dieting styles because it focuses only on what truly matters for weight loss, while not over complicating the dieting process with things that have no direct impact on weight loss to begin with. Believe it or not, all diets cause weight loss through the same mechanism. They work by causing a person to eat less, putting them in what's called a negative energy balance. This means that they are burning more calories than they are consuming daily, which is what actually causes weight loss. If you are in a negative energy balance, you will lose weight no matter what foods you consume .
This is commonly referred to as Calories In VS Calories Out or CICO for short . If you want to gain or lose weight, you must consume the correct amount of calories, regardless of what foods you eat. For weight loss, this would mean consuming less calories than your body burns in a day. There are no tricks to losing weight, you can NOT lose weight if you are not in a negative energy balance, no matter what types of foods you're consuming or how much exercise you're performing.
All styles of dieting cause weight loss through this mechanism. Keto doesn't cause weight loss because it puts you into ketogensis, it causes you to lose weight because most people following keto eat less overall calories . Low carb doesn't cause weight loss because you lowered your carbs, it causes weight loss because lowering your carbs caused you to go into a calorie deficit. Any other diet you can name works through this very same mechanism to induce weight loss. There are no magic tricks or special mechanisms behind these diets.
Flexible dieting does away with these pointless variables such as obsessing over keto friendly foods or carb intake and instead focuses on the mechanism that ACTUALLY causes weight loss, total calories. THIS is why it's so effective. It strips away all of the useless variables and is absurdly simple, yet effective.
A common concern is that eating "junk" food will result in a negative impact on body composition (the ratio of fat to lean mass your body is composed of). This shouldn't be of concern, however, because what affects body composition is total calories and macronutrient intake, but NOT where those macronutrients come from .
In other words, in terms of body composition, as long as you're eating adequate calories and protein, it doesn't matter where those calories and protein come from. Two people eating the same exact amount of calories and protein who have very different diets in terms of food choices will have nearly identical progress.
Flexible dieting can be done for both gaining and losing weight, but we'll focus on weight loss here as the topic of main discussion, since putting on muscle is an entirely different beast and requires articles of it's own.
The first step to setting up a flexible dieting plan is to find how many calories your body burns on average every day. This is often called your Total Daily Energy Expenditure or TDEE for short. Calculating your TDEE is considered the most effective way to determine daily calorie needs   . Your TDEE consists of two parts:
- Resting Energy Expenditure (REE): The amount of calories you burn when resting.
- Non-Resting Energy Expenditure (NREE): The amount of calories you burn through exercise, daily activities and digesting food.
If you were to eat this amount of calories daily, you would maintain the same body weight. Having this number gives you a starting point so that you know how many calories you should consume for weight loss, because weight loss, as mentioned, is simply a product of consuming less calories than your body burns (there are NO other mechanisms to weight loss, it's all a numbers game).
How to calculate your TDEE
The quickest and easiest method to finding your TDEE is to use one of the many TDEE calculators found online. It's important to note that these are just estimates based on basic information such as your weight, height and activity. Each person's body is different and you should therefore only use these calculators as a starting point, and then fine tune your calorie intake over time based on your body weight fluctuations.
The math used to calculate TDEEIf you want to know how it's calculated, read on. First, you can use the formula below to find your BMR, which is essentially how many calories you burn while at rest.
- Men: (10 x weight in kg) + (6.25 x height in cm) – (5 x age) + 5
- Women: (10 x weight in kg) + (6.25 x height in cm) – (5 x age) – 161
Then, the result is multiplied by an activity factor to estimate your TDEE. The activity factor you'll use will depend on your average daily activities. Here are the activity factors and the number that you would multiply your BMR/REE by.
- Sedentary (little or no exercise): x 1.2
- Lightly active (1–3 days per week): x 1.375
- Moderately active (6–7 days per week): x 1.55
- Very active (every day): x 1.725
- Extremely active (twice or more per day, elite athletes): x 1.9
The result from the above formula should give you a basic estimate of your TDEE. Though this is likely not your true TDEE, because energy expenditure varies from person to person and most of our activity fluctuates from day to day. If you want a more accurate TDEE, I suggest testing it in the following way:
- Get your estimated TDEE from the above formula.
- Eat exactly that many calories for 2-3 weeks.
- Weigh yourself once a week under the same conditions and note any changes.
- Considering that a pound of fat consists of roughly 3500 calories, we can do simple math to figure out your actual TDEE. If your estimated TDEE is 2500 calories, for example, and you lose one pound a week when eating this amount of calories, then we know your true TDEE is actually 3000, because you must have been eating in a weekly deficit of 3500 calories (or 500 calories below your true TDEE every day).
Once you have an accurate estimate of your TDEE, now you need to decide how much weight you'd like to lose per week. A pound of fat is roughly 3500 calories, meaning that to lose one pound of fat in a week you'd need to eat 500 calories BELOW your TDEE daily for a week (500*7- 3500). You can safely lose 1-2 lbs per week, but I wouldn't suggest going any higher than this. Once you decide on a weight loss rate, then you have your calorie goals for your flexible dieting plan.
The next step once you have your daily intake requirements for the rate of weight loss you want is to figure out how much protein you should take in for optimal fat loss. The range that is typically recommended is around 1.6–2.2 grams per kg of bodyweight. If you resistance train (you absolutely SHOULD for fat loss), then you'd likely want to stay on the higher end of this range  .
Now that you have your calorie and protein goals, all you need to do is eat whatever foods you enjoy while staying within your calorie limits and meeting your protein requirements. Nothing else matters and you no longer have to stress over unnecessary variables that make your diet miserable.
While flexible dieting is the most straightforward way to diet, it doesn't mean there aren't some drawbacks. Below I'll list some of the pros and cons of flexible dieting.
- Focuses on the actual mechanism behind body weight changes without adding any unnecessary complexity, making it both extremely simple and extremely effective at the same time.
- Very easy to adhere to due to the simplicity and lack of unnecessary complexity, reducing overall diet stress and chances of binge eating.
- Provides much more freedom for the dieter. Because it's less restrictive, there's less concern that you can meet your diet needs when you're out and about with friends and family.
- Can help keep weight off long term . Flexible dieting is less restrictive and therefore can be an easy diet to implement into your lifestyle and continue to follow long after you're done with weight loss.
- Diet may be too free for some. Some people have trouble controlling their portion sizes with certain foods and may be more likely to binge when they're allowed too much freedom with food choice. By eliminating certain food categories, it makes it easier to stay on track and avoid eating impulsively.
- Micronutrient (vitamins & minerals) intake may suffer for some who eat mostly foods that lack healthy amounts of these nutrients. Because it is up to the dieter how they reach their calorie and protein goals, there is a chance that the foods chosen are low in micronutrients. While this won't affect body composition (the way you look), it can affect health in the long term.
- Calories must be tracked very accurately for the best results. Some diets, such as keto, naturally result in less overall calories consumed because of the types of foods they focus on which happen to be lower in calories. With flexible dieting, calculating calories and making sure you're in a deficit is very important, so all food intake must be tracked strictly.