Four Dangers of Underfueling

If weight loss is your goal, creating a calorie deficit (burning more calories than you consume) is essential. So then, it seems logical that a larger deficit would lead to faster weight loss. Read on for four dangers of undereating…

If weight loss is your goal, creating a calorie deficit (burning more calories than you consume) is essential. So then, it seems logical that a larger deficit would lead to faster weight loss… right? It’s not quite that simple.

When developing a weight loss plan, understanding your individual resting metabolic rate (RMR) is crucial. Your RMR represents the calories your body expends on essential, life-sustaining functions like breathing, blood circulation, and digestion. It's vital to consume enough calories to meet your RMR to ensure proper organ and muscle function. In fact, consuming fewer calories than your RMR can lead to health consequences and may even impede your weight loss progress. Let’s explore what happens with undereating: 

1. Decreased Fat Loss

   • The body has many processes naturally in place to protect itself and ensure survival. When you eat less calories than your RMR, you are essentially restricting the energy your organs need to function. If this continues for a prolonged amount of time, the body eventually starts to decrease the calories it uses for survival by slowing down voluntary movement and dropping your RMR. This can make it increasingly more difficult to remain in a calorie deficit, stalling fat loss. 

2. Loss of Lean Mass

   • Much like your vital organs, lean mass itself requires adequate energy intake to be maintained. Lean mass includes everything except fat mass in the body (muscle, organs, bones, and skin). When one is severely undereating, the body will start to break down lean tissue to serve as an energy source, leading to muscle weakness, decreased balance, joint pain, and increased fatigue. Over time, extended loss of lean mass can greatly increase risk of injury when performing physical activity.

3. Decreased Energy

   • Remember, your body wants to protect itself! When eating well below your energy requirements, non-essential activities and training are not a priority. So it’s no surprise that you’ll feel fatigued when carrying out simple everyday tasks, experience brain fog, and have trouble hitting your workouts. 

4. Hormone Imbalances

   • Because undereating impairs proper organ function, hormone production and regulation is also disrupted. This can unbalance stress, thyroid, reproductive, and hunger hormones, leading to side effects such as missed periods in women, irritability, mood swings, weight gain, and altered hunger cues.

The human body is a complex and intricate system, constantly working to keep you alive. Don’t make it work harder by over-restricting your nutrition! If your goal is to lose weight, working with a registered dietitian will help you reach your goal in a manner that is safe, practical, science-based, and ensures that you continue to feel your best physically and emotionally. Here at Nutriworks, we have a team of dietitians who can work with you to create an individualized plan that is perfect for you and your needs!