I have several posts on calories, how they work, how many one should consume, what kinds should we eat, how to figure out how many we’re burning. I realized they’re spread out all over my blog, so decided to cobble them together in one post to make it a little easier to get the whole picture. There are two main themes: how much should we eat (how many calories), and WHAT should we eat (what KIND of calories). I attempt to simplify it for the folks who don’t want to spend all their free time reading scientific studies. So without further ado…
How Much Should I Eat?
There’s a lot of confusion out there, so in the name of clarity, I’ll give you the basics on calorie intake, as simply as possible. A calorie is a unit of energy. Your body uses energy to fuel your daily activity. If you take in more energy than your body uses, it stores the excess, usually as fat, but if you’re lifting heavy and using your muscles it can and will use that excess energy to build muscle too. That’s what we want.
If you’re at a healthy weight and your goal is body recomposition, you need to eat AT LEAST as many calories as your body burns, preferably a little bit more. Your body needs raw materials to build muscle, and if it’s using all the calories you eat to fuel your activity there will not be any left to build muscle with. If you’re undereating at a healthy weight, your body will do whatever it can to burn fewer calories, so will slow down your metabolic processes and start burning muscle for fuel, because muscle requires more calories to maintain than fat. If you’re undereating, that muscle is taking up energy (calories) that your body would rather use to fuel your heartbeat and brain activity.
If you’re obese or overweight, you need to burn more calories than you consume to lose weight. Not too many more, I generally recommend keeping a 500 calorie deficit (or less) to keep your metabolism healthy. That deficit should get smaller as you get closer to your goal. Alternately, you can use a calorie calculator to figure out how many calories your body will need to maintain your goal weight (including your activity), and eat that many calories. Your body will take care of the rest (that’s how I did it). If you keep your deficit relatively small and lift weights and get regular exercise, your body will tag your muscles as ‘in use’ and preserve them, burning stored fat to make up the deficit in energy in vs energy out. If you’re sedentary, your body will burn lean mass as well as fat to make up for that deficit.
NONE of this means that diets that don’t require calorie counting don’t work. It just means that, for some people, those diets help them to naturally and instinctively consume the number of calories that will support their goals. Different people can experience this with different diets. Some people (like me) don’t ever experience it (or at least I haven’t yet, and I’ve tried all the diets) and need to be at least somewhat aware of our energy requirements. And we need to eat enough to fuel our activity and support our goals. Restricting calories below that level is counterproductive and will ultimately lead to failure. For most people, including women over about 100 pounds, that means eating at least 2000 calories a day, much more for most of us (I eat about 3000 most days). Even to lose weight, very few of us will need to drop below that, and if we do we are setting ourselves up for a damaged metabolism and fat storage.
Here’s a calorie calculator that I find realistic and helpful, it won’t give you an unsustainably low calorie target, in fact you will likely be surprised by just how much you need to eat to stay healthy and support your goals:
What Should I Eat?
Invariably, every time I say that weight is a product of energy balance (ie, calories in vs. calories out) I get at least one person arguing ‘calories don’t matter! different kinds of calories affect the body differently!’.
I can’t really blame people for the confusion. There are a shit ton of diet gurus out there muddying up the waters with claims that combining foods ‘properly’ or cutting out certain foods or macronutrient groups is really the key to weight loss and that all you have to do is eat the ‘right’ foods and you’ll be able to eat all you want and still lose weight. Oh, and conveniently they just happen to be selling a list of those approved foods. Calories DON’T matter they claim, it’s the KIND of calories you eat that matters. “Those people who tell you to just eat less have got it all wrong” they say. “‘They’ have been misleading you, I’m telling you the TRUTH.”
All that black and white thinking has got people believing a false dilemma: It’s EITHER ‘calories in vs. calories out‘ OR ‘the kind of calories you eat‘ that matters! It’s a big ole’ moneymaker. They tell you they have the secret diet that will allow you to eat all you want and still lose weight, and you open up your wallet and buy it.
Here’s the truth, and I’m not going to charge you for it: weight is a product of energy balance, AND the kinds of calories you eat.
Lets start with the basic equation X +/- Y = Z, where X is calories in, Y is calories out and Z is total weight. The KINDS of calories you choose can affect the values of X and Y (Y moreso than X), but here’s where the diet gurus are misleading you: changing the values of X and Y doesn’t change the basic equation.
Some foods cause your body to burn more calories than others. Protein and fiber rich foods require your body to do more work to digest. It’s called the ‘Thermic Effect of Food‘. Eating foods with a high thermic effect makes your body burn more calories (Y), sometimes a LOT more calories. That’s why the list of approved foods your guru sells you will be comprised primarily of protein-rich foods and fiber-rich vegetables. Both are highly thermic. There’s also some evidence that whole, minimally processed foods are more highly thermic than equivalent processed foods (Y). Eating good quality nutritious foods can increase your energy level, which can lead to more spontaneous activity, which leads to a higher calorie expenditure (Y). Eating highly satiating foods can also cause a spontaneous reduction in total calorie intake (X). Protein and fiber, again, are highly satiating. As our understanding of the ways food affects our bodies grows, I suspect we will discover other ways that the kind of calories we choose can change the values of X and Y.
Eating a rich and varied diet full of whole, protein- and fiber-rich foods can absolutely change the way your body functions! In the end, however, it is still subject to the laws of thermodynamics. In an energy surplus it will store that surplus as mass (either muscle or fat depending on your activity level), and in an energy deficit it will burn stored energy reserves to fuel activity. Your task is to eat (and move) in a way that increases your energy expenditure to a level that exceeds your energy intake, if weight loss is your goal. Eating less isn’t the whole story, and sometimes eating MORE will produce a higher Y variable and weight loss will ensue, but optimizing your individual X and Y variables IS the way to get the Z you desire.
Creating your ideal diet: Macros and Micros
Protein and vegetables are GREAT and you should try to get lots, but eat fat and carbs too! Carbs are not the devil, eat lots of real whole foods like fruits and starchy vegetables, and grains if you tolerate them. If you have a medical reason to restrict carbohydrates, work with a registered dietician to make sure you’re meeting all yoru micronutrient needs. Fat fills you up and makes food taste good, and your body needs it for proper nutrient absorption and hormonal function. Tracking your diet can be helpful for many reasons, my favorite diet tracking website is fatsecret.com because it gives a more realistic, sustainable calorie target than most other diet tracking websites, which ensures that you’re getting enough calories to support your activity. It's not just about calories, regular tracking will help you learn to meet your energy requirements with foods that also provide the vitamins, minerals and adequate amounts of fat and protein to support good health and weight management. It can be a pain at first, but over time it helps you fine tune your diet to suport your individual needs, preferences and goals. Calories DO matter, but most of us can eat a lot more than we think we can. Tracking calories is NOT about restriction, and reaching/maintaining a healthy weight is NOT about being hungry and denying ourselves proper nutrition. Quite the contrary, it is about feeding ourselves adequate amounts of (mostly) nutritious foods that support health, energy and vitality. Here is a tool that will help you determine how many calories your body needs to function properly. Many of you will be surprised at how high the number is. Mine is as much as 3500 a particularly active day. Hardly restrictive. Aim for, at minimum, .5 ' 1 gram of protein per pound of body weight a day. Fat should make up at roughly 20-35% of your calories (some people do well on lower or higher fat percentages, but 20-35% is a healthy range for most of us). The rest of your calories can come from whatever macronutrient you prefer (macronutrients = protein, fat and carbs). If you're doing a lot of endurance exercise, go for more carb dense foods. It’s looking like the only 'bad guys' are refined seed oils and trans-fats (even refined sugar can be helpful under certain circumstances such as recovery from anorexia and digestive malabsorbtion issues), and by including more whole foods in your diet you will be reducing your intake of those in the form of processed foods. So after all this, I come back to: eat real food, but don't obsess! Make mostly healthy choices, but it’s also ok to eat foods purely for pleasure. Your diet has got to be enjoyable to be sustainable.
**A note to the nutrition nerds: yes, I’ve simplified things. That’s what I do here on my blog. This post isn’t for you, it’s for non-nutrition-nerds who don’t want to spend all their free time reading diet blogs and scientific abstracts.**