Friends, it’s time for some real talk and this is going to be a long one. I hope you’ll stay with me to the end.
Day after day I work with clients who are trying to lose weight and somehow got the idea that 1,200 calories is the standard for weight loss. This blog post from last September did a great job of articulating my feelings about that at the time. The most terrifying thing for me is that people are taking it to even greater extremes and I see it in both my clients and some of the people who have added me as a friend on My Fitness Pal.
“If 1,200 calories is good or recommended for weight loss, then eating even fewer should help me lose more, faster.”
The emphasis on the magical number 1,200 drives me nuts and the consumption of even fewer calories is scary. The origin of that number, at least I would assume, is that 1,200 is the number a woman should never drop below for safety’s sake, based on an average woman’s basal metabolic rate. Do you get what that means? By eating fewer than 1,200 calories you may be putting your body at risk. Frankly, 1,200 is even too low for the vast majority of people. Yet I see people eating between 700-800 calories.
At a very basic level, to lose weight you need to consume fewer calories than you use. Calories in versus calories out. We’ve all heard that and for the most part it’s true. Just because it’s true doesn’t mean that’s all there is to it. It isn’t that simple. Let me repeat, it isn’t that simple!
Your body is smart. It wants to protect itself and it knows it needs to be nourished. Each body is unique and each person has slightly different caloric needs based on the amount of nourishment needed to feed muscles and healthy tissue. Newsflash: your organs are included in that!
Consume fewer calories than you need to nourish these muscles and tissues and your organs will slowly shut down. Emphasis on slowly. It isn’t going to happen immediately and as true as starvation mode is, it doesn’t happen fast enough for most of us to take it seriously. I doubt a single person hasn’t heard of starvation mode, especially those trying to lose weight.
One of the biggest problems is in the name. When people are consuming fewer calories than they need, there comes a time when the metabolism slows and the person genuinely doesn’t feel hungry very often. This in itself leads people to dismiss the idea of starvation mode. “If I were starving, I would feel hungry! I feel fine.”
People seem to also be skeptical that starvation mode exists. The misconception is that in starvation mode you’ll put on weight and many people think, “If that’s true, how do people with anorexia continue to lose weight?”
Starvation mode does not lead to your body putting on weight. It leads to a slowing of weight loss in an attempt to conserve what energy it has. When your body isn’t getting adequate nutrients, it will turn to your own tissue to nourish itself.
Your muscles are more nutritious than your fat. Think about that. When your body is lacking the nutrition it needs to continue to function, it will turn to the most nutritious source and you will lose muscle mass. You will also lose bone mass and could start losing your hair, getting brittle nails, etc. Your body prioritizes continuing to function over everything else.
When you lose muscle mass, your metabolism will slow down, making it harder to burn fat and much more likely that any weight you lost during this time will be put back on. Not in the form of muscle, but in the form of fat. This is why crash dieting can lead to an even bigger weight gain afterward than was lost initially.
So how many calories does your body need to maintain your muscle mass? That is based on your Basal Metabolic Rate. What is metabolic rate, really? From the American Council on Exercise (ACE):
Metabolic rate represents the number of calories needed to fuel ventilation, blood circulation and temperature regulation. Calories are also required to digest and absorb consumed food and fuel the activities of daily life. Or put another way, metabolic rate is an estimate of how many calories you would burn if you were to do nothing but rest for 24 hours. It represents the minimum amount of energy required to keep your body functioning.
Basal Metabolic Rate (BMR) is a little different from Resting Metabolic Rate (RMR). The main difference is that BMR is taken in a darkened room immediately after waking and 12 hours of fasting to get an accurate reading while RMR readings tend to have fewer restrictions. There are several ways to measure this number, but one of the most common (and considered one of the most accurate without gas analysis through either direct or indirect calorimetry, which is the most accurate measurement), is the The Mifflin-St Jeor equation for estimated RMR:
10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) + 5
10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) – 161.
Using this equation for my own metabolic rate resulted in over 1,500 calories. Using the BodyGem at work, which is an indirect calorimeter and more accurate than the equation, resulted in almost 1,700 calories.
This means that if I do absolutely NOTHING all day, I burn between 1,500-1,700 calories to exist in my current state.
When I eat fewer than this number of calories, I’m already at a calorie deficit, meaning I will lose weight. If I am also exercising, that changes my metabolic rate and means that to maintain my weight I’ll need to eat more. The more muscle you build, the higher your metabolic rate, which means you’ll need more calories.
If you’re eating fewer calories than your BMR or RMR and you’re exercising, you may be putting yourself in an extreme calorie deficit. This is one reason why those eating fewer than 1,000 calories per day feel too weak or fatigued to exercise. You’re not even eating enough for your body to rest!
This number isn’t taking into account even sitting at a desk all day. For that you need to check out your daily caloric need. A great calculator for that can be found here. When I put my info into that and indicate that I’m moderately active (3-5 workouts per week), my daily caloric need is 2359 calories!
Check out this calculator to determine your daily caloric need and then subtract either 500 calories per day to lose 1 pound per week or 1,000 calories per day to lose 2 pounds per week. Since the calculator already took exercise into account, this is the number of calories you should be eating.
With 3-5 days of exercise per week, I can lose 2 pounds per week (the upper limit for healthy weight loss), by eating 1,359 calories per day. Even if I eat 1,859 calories per day, I’ll lose a pound per week. The most important thing is that I will not lose muscle mass and am not at a risk of malnutrition, starvation mode, brittle bones, etc.
You do not need to eat 1,200 calories or less to lose weight! You should not eat 1,200 calories per day or less unless you are particularly petite and that’s what your calculation indicates.
It is super important to note that if you have been eating too few calories and increase to your healthy calorie range, your body may respond at first by putting on weight. This is normal and necessary. Your body WILL stabilize and you’ll replenish your muscles, bones, and vascular system then you will start to lose fat. Trust the process and give it time.
If you’re still with me, bravo! I know this is a lot of information, but the primary takeaway is that you don’t need to (and shouldn’t) starve yourself to lose weight. Eat nutrient dense foods, adequate calories to maintain your muscle mass, and move more to lose weight.
If you’ve learned anything from this post, please share it. We need to spread the word. I would also love to hear your thoughts.