Why Losing Weight Fast Isn’t a Good Idea, and What to Do Instead
2023-09-21 16:54Everyone wants to know the fastest way to lose weight. And with so many diets promising just that, it's no surprise the trend continues.
Anything that sounds too good to be true most likely is. Rapid weight loss fad diets are usually gimmicks and are largely unsafe. Plus, losing weight too fast has some significant downsides.
The key to losing weight and keeping it off is approaching it in a sustainable, thoughtful, and balanced way.
If weight loss is your goal, consulting with a health care professional, like a registered dietitian, can help you develop an individualized plan that's sustainable, realistic, and compatible with your lifestyle.
What is Considered Fast Weight Loss?
Rapid weight loss is at least a 5 percent reduction in body fat within five weeks. This equates to approximately two or more pounds per week, depending on an individual's body weight.
Healthy Rate of Weight Loss
Slow and steady, or "healthy," weight loss is 0.5 to 2 pounds per week and an ultimate goal of 5-10% of total body weight within the first six months.
But if healthcare professionals recommend weight loss of one to two pounds per week, why is more than that dangerous? Studies find that both slow and rapid weight loss are effective in reducing body weight, but the faster you lose weight, the more lean mass you'll burn and the more likely you will gain it back over time.
Why is Rapid Weight Loss Dangerous?
There are many evidence-based reasons supporting the dangers of rapid weight loss, including loss of lean muscle mass, disordered eating habits, unsafe use of supplements, and more.
It Doesn't Preserve Lean Muscle
Weight loss and fat loss are not the same. You can lose weight without losing body fat. If this happens, you lose lean body mass, such as muscle, organ tissues, or water weight. Losing lean mass has several negative health consequences, including fatigue, increased risk of injury, low energy, reduced metabolism, and a decline in neuromuscular function.
One study comparing the effects of rapid weight loss and slow weight loss on body composition found that both diets resulted in weight loss and improvements in blood sugar and cholesterol levels. However, the slow weight loss group saw greater improvements in body composition. That means losing weight slowly helps preserve muscle while losing weight quickly does not.3
When losing weight, it's important to focus on preserving lean mass (muscle) so that you end up losing primarily body fat and shift your body composition