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Understanding the risks of rapid weight reduction strategies

July 10, 2024
9 minutes
Personal Health
Personal health journeys

Perhaps you have a big event coming up in a few weeks, or you're excited for a first date that you finally feel good about. Maybe you're prepping for a job interview, or you're getting ready for a vacation. There are many reasons why people search for terms like "how to lose weight fast" and "quick weight loss diet," but sadly, quick-fix weight loss often does more harm than good.

We get it—the promise of quick results can make rapid weight reduction strategies tempting. When you've decided that you're ready to start feeling better in your own skin, you want to get to your goal as soon as possible.

At Evidation, it's our goal to help you feel great, look great, and achieve optimal health. Here, we'll explore why rapid weight loss can be counterproductive to maintaining a healthy weight long-term, the physical and mental health risks that come with rapid weight loss, and how you can create a sustainable weight loss plan that will leave you feeling energized and motivated—not exhausted and insatiably hungry.

The impact of rapid weight loss on metabolism

Rapid weight loss doesn't just leave you ravenous in the short-term—it can also lead to metabolic changes that complicate long-term weight management.

When weight is lost quickly through significant calorie restriction, the body's basal metabolic rate (BMR)—the amount of calories the body burns in order to maintain basic physiological functions while at rest—decreases. From an evolutionary standpoint, this makes sense, as the brain and body receive the message that food is scarce.

By decreasing the number of calories your body burns at rest (a process known as metabolic adaptation or adaptive thermogenesis), your metabolism increases the likelihood that you'll make it out on the other side of a famine or other disaster. When your BMR drops, it makes weight loss more difficult, and can make it easier to regain the weight you've lost.

Loss of muscle mass is another factor that can cause the body's BMR to drop. Muscle is a metabolically active tissue, meaning it uses more calories when the body is at rest than other types of tissue. When we lose weight rapidly, we often lose muscle along with fat and water. This means that while the scale may be showing weight loss, the weight that's being lost may negatively affect weight loss and maintenance efforts in the future.

Your endocrine (hormone) system can also be disrupted when you lose weight too quickly. Hormones that can be affected by rapid weight loss include:

  • Leptin: Produced by fat cells, this hormone works to regulate the body's energy balance by suppressing hunger. When you lose weight quickly, your body's leptin levels decrease, leading to increased appetite and a decreased BMR.
  • Ghrelin: Known as the hunger hormone, ghrelin stimulates appetite. When we lose weight too quickly, ghrelin levels tend to increase—perhaps as an evolutionary last-ditch effort to encourage our ancestors to procure and eat a healthy amount of calories.
  • Thyroid hormones: Your thyroid works to regulate your metabolism. Losing weight quickly can reduce the amount of thyroid hormones your body produces, which can lead to lower energy expenditures and slower metabolic processes.
  • Insulin: While weight loss is typically positive for people who are diabetic or pre-diabetic, rapid weight reduction can cause dangerous blood sugar and insulin fluctuations that can cause metabolic disturbances.

If you've used rapid weight loss strategies before and fear that you may have negatively affected your metabolism, it may be more difficult—but not impossible—for you to lose weight in the future. If you have a history of yo-yo dieting or rapid weight loss, it's a good idea to talk with your doctor about what type of nutrition and exercise plan will best support your weight loss efforts.

Health effects of losing weight too quickly

Your metabolism isn't the only bodily system that can be negatively affected by losing weight too quickly. Some of the additional health effects of rapid weight loss include:

  • Nutrient deficiencies: Nutrient deficiencies are common among people who lose weight fast, as it can be difficult to maintain a low calorie diet while still consuming all the vitamins and minerals that the body needs to thrive. Many people who lose weight too quickly find that they feel tired and get sick more often. Providing the body with the right nutrients in the right dosages can help to boost your energy and support a healthy immune system while you're working to lose weight.
  • Gallstones: When your body loses weight quickly, the liver releases extra cholesterol. While this effect is usually temporary, you may experience the formation of gallstones. These hardened bile deposits can cause sudden and intense abdominal pain, nausea and vomiting, and more. If you develop gallstones and experience symptoms, you'll likely need to have surgery to have them removed.
  • Loss of bone density: Your body needs adequate nutrients to support your bone health. When you work to lose weight through crash dieting, it's likely that your body is not getting all of the bone-healthy nutrients necessary to keep you healthy and strong, leading to an increased risk of fractures and osteoporosis.
  • Cardiovascular stress: Weight loss is taxing on the heart, and it's important to prioritize your cardiac health as you're working to become your healthiest self. Extreme and rapid weight loss can stress the cardiovascular system, eventually leading to arrhythmias or other dangerous cardiac issues. If you've gone through extended periods of extreme weight loss, it's a good idea to talk with your doctor about any health screenings you may need to protect your heart.

Psychological effects of rapid weight loss

We know that rapid weight loss wreaks havoc on the body—but it can also harm your mental health. The psychological effects of rapid weight loss are unfortunately myriad, and can require help from a trained mental health professional to overcome.

Some of the psychological issues associated with rapid weight loss include:

  • Increased eating disorder risk: Some people who lose weight quickly find that they develop unhealthy eating behaviors and an obsessive focus on how they look. Anorexia nervosa, bulimia nervosa, and binge eating disorders can all take hold following a period of rapid, unhealthy weight loss.
  • Increased stress and anxiety: While going through a period of rapid weight loss, it can be hard to stick to the rules and regimens that come with a serious cut in calories (and a serious uptick in exercise). Some people find that sticking to a strict diet can cause constant feelings of stress and anxiety. These negative issues can become even more difficult to handle if the person who is crash dieting is afraid of regaining the weight.
  • Mood swings: In order to stay calm and productive throughout the day, it's important to provide your body with the nutrients that it needs to thrive. Severe calorie restriction can result in irritability and a lack of mood regulation, and can eventually alter brain function.
  • Obsessive thoughts: There's nothing wrong with thinking about the foods that help you feel your best. That being said, you're venturing into dangerous territory if you're beginning to obsess about your weight loss plan. If you're noticing obsessive thoughts about your body image, weight, or the food you eat, it's a good idea to reach out to a mental health professional who specializes in obsessive thoughts (OCD) and/or eating disorders.

Many people who have experienced rapid weight loss followed by rapid weight gain feel discouraged and unmotivated to keep working to get healthy. It can be helpful to remind yourself that once you lose weight the right way, you’re more likely to keep it off. Making one healthy decision at a time, and taking the process one day at a time, can help to move you toward your goal weight.

Sustainable weight loss: a healthier alternative

Exercising regularly and eating the right amount of calories for your body sounds simple, but doing so is often easier said than done. Understanding your caloric needs, properly estimating the amount of calories you burn during exercise, and managing your stress levels can all help you reach your weight loss goals.

To create a plan for sustainable weight loss, it's important to start by understanding your unique caloric needs. While understanding your body mass index (BMI) can give you some insight into how many calories you're burning each day, a registered dietitian or nutritionist can help you determine how to create a healthy meal plan that you love to support your weight loss efforts.

Not quite ready to reach out to a professional for help with your diet? We get it! It can take some time to understand how different foods affect your body. Keeping track of what you eat can help you identify patterns and find weak spots that are keeping you from hitting your goals. If you're struggling to understand where you're at nutritionally, you may want to take a week or two to log all the drinks and food you consume, allowing you to get a crystal-clear picture of your starting point. Remember, there's no need for shame—you're working hard to get your health on track, and that's an admirable pursuit.

You'll also need to accurately estimate the amount of calories that your body burns while you're exercising. Using a wearable fitness tracker can help motivate you to keep moving during the day. You may notice that different apps and tracking devices provide you with different estimates of how many calories you burn during physical activity. Stick to a single wearable fitness device and/or fitness tracker that you enjoy, wear it consistently, and set achievable movement goals that will keep you motivated and moving forward.

Finally, reaching out for help is often a key part of a sustainable weight loss plan. If you're experiencing physical health issues due to past rapid weight loss, it's important to talk with your doctor or other healthcare provider about potential issues that may need to be addressed before you begin a new weight loss plan. If you find that you're obsessing over calories eaten and calories burned, it's a good idea to talk with a mental health professional who specializes in eating disorders.

There's no need to try and drop weight quickly—as you know, when you lose weight rapidly, it comes back just as quickly as it left. Setting a goal of losing 1 pound per week gives your body the time it needs to adapt to your new, post-weight-loss metabolic needs, and also provides your mind with the time it needs to become accustomed to new, healthy behaviors.

Common myths about rapid weight loss debunked

If you've been spending some time searching for information about how to lose weight quickly, it's likely that you've spent plenty of time reading contradictory articles, leading you to wonder what's true and what's false when it comes to weight loss.

Let's take a look at some of the most common myths about weight loss:

Myth: You have to avoid carbohydrates in order to lose weight.

Truth: Carbs hold water, and when you cut them out of your diet, you're likely to experience a quick drop in water weight. That being said, carbs are an essential source of energy that can keep you pushing through a tough workout. Eating the right carbs at the right times can help you feel your best and move toward your healthiest sustainable weight.

Myth: You can't snack and lose weight.

Truth: If you're experiencing extreme hunger regularly, it's likely that your plan isn't sustainable. Fiber-packed snack options like vegetables, fruits, and nuts can help to hold you over to your next meal when you're feeling peckish.

Myth: Nighttime eating leads to weight gain.

Truth: Weight gain happens when you consistently take in more calories than you burn. It doesn't matter what time of day you eat, as long as your meals are contributing to your energy levels in a way that helps you feel your best.

When it comes to weight loss, looking for a quick fix typically backfires. No matter where you're at on your weight loss journey, exploring sustainable ways to improve your health will carry you closer to your goal.

Sustainability is key when it comes to creating a weight loss plan that works. You're likely already using apps like Lose It!, Apple Health, FitBit, and other fitness and nutrition trackers—and at Evidation, we're here to help you put the health data you share with us to good use. With your permission, we use the health data you're already tracking to provide you with insights that can help you understand how you can take your progress to the next level. Learn more and download our app today to learn more about healthy eating, get the accountability you need to stay on track, and get rewarded for engaging in the healthy activities you're already doing.

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