You’ve probably heard that if you want to drop a few pounds, it’s all about “calories in versus calories out.” On one level, it’s true; you can cut calories to lose weight. And the more you starve yourself, the thinner you’ll continue to get. But at what cost?
Cutting calories drops weight but preserves fat while whittling away at your muscle. This sets you up for a metabolic disaster. When you’re tired of being tired all the time and decide to eat more calories, your metabolism remains low. So not only will you gain your weight back, you’ll likely add on extra.
The good news is, weight loss isn’t that big of a mystery, and science knows there’s a better way. Read on to learn why cutting calories alone is the worst way to lose weight and what to do instead.
The Failure of Calories In vs Calories Out
Calories in, calories out will indeed help you lose weight, but you’ll lose lean body mass in the process. This not only has negative health implications but makes long-term weight loss unsustainable. There are three main reasons why a calorie deficit for fat loss simply doesn’t work.
1. A Calorie Deficit For Fat Loss Depletes Your Muscle Too
When you restrict calories to lose weight, your body drops pounds from three main areas; you lose water weight, lean body mass, and fat. If you’re losing weight for health, you want to preserve hydration and lean body mass while decreasing body fat.
Fat is the most metabolically dangerous1 tissue type while lean body mass, aka muscle, plays an important role in maintaining a healthy metabolism and hormonal balance. When restricting calories alone, the body doesn’t know to hold onto muscle and drop just the fat.
2. A Calorie Deficit to Lose Weight Slows Your Metabolism
Are you cutting calories but not losing weight? We’ve all experienced the effects of yo-yo dieting. We cut calories, lose weight, then gain it all back (and then some) as soon as the diet’s over. There’s actually a scientific explanation for this. When we create a calorie deficit by eating fewer calories than we burn, our metabolism slows down2.
This weight-loss paradox is the reason why it’s easiest to lose weight at the beginning but harder the longer we’re on a diet. Even in people who never work out, resting metabolic rate accounts for nearly 70%3 of energy expenditure. When metabolism slows, it’s a really big deal.
3. The Damage from Caloric Restriction May Be Irreversible
A slower metabolism isn’t just a temporary effect of caloric restriction. Unfortunately, when you cease restricting, your metabolism can take years4 to recover. This explains why we not only gain back our weight when we return to our pre-diet caloric intake, we gain even more!
So what causes this horrific slow metabolism response? Researchers use the term [adaptive thermogenesis[^5 to explain how muscle loss, changes in hormones, and reduced physical activity all conspire to keep us in balance.
When restricting calories for fat loss, your body makes its best effort to conserve energy because it thinks it’s not getting enough.
What you may not know is that there’s a way to hack this system. You can lose body fat and preserve muscle by eating as much as you want, just differently.
How to Lose Fat While Preserving Muscle
Your muscle mass is vitally important5 to your health. Not only does it look good, but it keeps your resting metabolic rate high, promotes a healthy hormonal balance, and keeps you functioning. So a weight loss strategy that preserves muscle mass is of high value.
The following three methods are scientifically proven to help you preserve muscle while losing fat. The three methods work best when combined.
1. Intermittent Fasting for Fat Loss
In comparing intermittent fasting vs calorie restriction, experts agree intermittent fasting is better than long-term dieting to kickstart your metabolism and burn off fat cells. With intermittent fasting, you alternate between periods of eating and restricting. It’s highly effective and boasts benefits that go beyond fat loss.
Unlike caloric restriction, intermittent fasting boosts your metabolism. This boost comes from changes to your insulin response and a process called ketosis. Fasting triggers a[metabolic switch6 which actually tells our body to burn fat.
In addition, intermittent fasting promotes human growth hormone7 and testosterone8, two key hormones for preserving and building muscle. More muscle equates to an improved body composition and even greater fat loss.
2. Eat More Protein for Fat Loss
In 2016, researchers at Canada’s McMaster University noticed just how important dietary protein9 is for those who want to lose fat while preserving muscle. During their study, two groups cut calories by an astonishing 40% while continuing to exercise intensely. One group ate a diet high in protein, while the other did not.
Surprisingly, the high-protein group experienced 2.5 pounds of muscle gains, even while deficient in calories. In addition, they lost about 1.5 more pounds of fat than their low-protein counterparts.
The lesson learned? Even if you cut calories, don’t cut protein. Not only will this help preserve your muscle, but protein consumption helps promote fat loss10.
3. Work Out Intensely to Lose Fat
When sustained, high-intensity movement will also help preserve your muscle while you’re losing weight. In the above study, the low-protein cohort didn’t gain any muscle, but they did preserve what they had. Their intense workouts prevented muscle loss despite their caloric deficit. Exercise, specifically[resistance training 11, signals the body to preserve muscle when energy intake is low.
The problem with long-term caloric deprivation is that it makes you too tired to perform12. Low glucose, iron, folate, and B6 can all result from caloric restriction, causing fatigue. In contrast, alternate day fasting 13 has shown promise in improving athletic performance and efficiency of energy usage.
The Best Way to Lose Weight?
A calorie deficit for fat loss is counterproductive. Restricting all-around calories, especially for the long term, promotes fat storage, slows metabolism, and sets you up for a greater weight gain in the future.
To lose weight and keep it off, a combination of intermittent fasting, a high protein diet, and intense exercise is your best bet.
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