One of the main reasons that undereating can lead to weight gain is because consuming too few calories can cause your resting metabolic rate to slow down. This means you may burn fewer calories throughout the day.
You will not gain weight from eating too few calories.
There are many reasons why it can seem like under-eating can lead to weight gain. But, science has shown over and over again that this isn't physiologically possible.
You Might Be Eating Too Little
This phenomenon is called “starvation mode,” and while your body isn't actually starving, it will naturally hold onto whatever calories it receives in an effort to help you maintain your energy balance.
Would you believe that eating less can result in more belly fat? It's true. While intuitively it makes sense that eating fewer calories will lead to a flat stomach, the reality is that because of the effects undereating can have on certain hormones, not eating enough can lead to fat accumulation on your midsection.
Too few calories can hamper your metabolism, sabotaging any goal to lose weight. Although some combinations of macronutrients or types of foods may affect weight loss synergistically, when it comes to dropping pounds, there's no denying that calories matter.
However, other studies show that while consuming 1,000 calories a day may result in significant weight loss, most people cannot sustain it and often experience significant weight regain . The reasons include regaining lost muscle mass and increased appetite. Also worth noting is that the human body can adapt.
Diet: There is no magic diet for belly fat.
But when you lose weight on any diet, belly fat usually goes first. Getting enough fiber can help. Hairston's research shows that people who eat 10 grams of soluble fiber per day -- without any other diet changes -- build up less visceral fat over time than others.
Some people go on a very low-calorie diet for rapid weight loss, often consuming only 800 calories a day. This type of diet usually includes special foods such as shakes, bars, or soups to replace meals and for added vitamins. Very low-calorie diets can help a person achieve weight loss of up to 3 to 5 pounds per week.
Consuming at least 1,200 calories per day has often been touted as the minimum for basic bodily functions and to stay out of starvation mode, but the amount is actually too low. A healthy amount of calories for adult women ranges from 1,800 to 2,400 calories per day and for men it's 2,000 to 3,200 calories per day.
However, calorie intake should not fall below 1,200 a day in women or 1,500 a day in men, except under the supervision of a health professional. Eating too few calories can endanger your health by depriving you of needed nutrients.
Muscle is denser than fat.
While one pound of fat weighs the same as one pound of muscle, muscle occupies about 18 percent less space. In addition, muscle burns calories while fat stores them. So, if your weight isn't decreasing but your clothes are starting to fit more loosely, you may be building muscle.
Some people may choose to restrict their daily intake to 1,500 calories. While factors such as age, gender, and activity level can cause caloric needs to vary, a 1,500-calorie intake is typically less than the average person requires. As a result, this diet may help some people lose weight.
If you're not getting enough calories, chances are you're not getting enough vitamins and minerals either. Nutritional deficiencies may cause a long list of health complications including, but not limited to, anemia, infertility, bone loss, poor dental health and decreased thyroid function.
For those who need fewer calories, a 1,200 calorie diet is usually safe and potentially effective. The number of calories a person needs each day depends on several factors , including their age, sex, activity level, and body size.
Short-term risks of eating 1,000 calories a day may include dizziness, hunger, gallstones, nausea, fatigue, headaches, and nutrient deficiencies. It can lead to nutrient deficiencies, slow metabolism, and make bones weaker if you exercise along with a low-calorie diet.
In addition to sabotaging your weight-loss efforts, eating too few calories can also harm your health. When your body goes into starvation mode, you are at increased risk for the following: Abnormally low blood pressure and slow heart rate. Heart rhythm abnormalities.
You feel lethargic.
Without enough calories, you will quickly experience feelings of fatigue. Because your body doesn't have enough calories to burn and generate energy.
One reason belly fat is so hard to lose is that it's considered an “active fat.” Unlike some fatty tissue that simply sits “dormant,” belly fat releases hormones that can have an impact on your health — and your ability to lose weight, especially in the waist and abdomen areas.
Some other signs of fat loss are:
It leads to a slimmer appearance and more muscle definition. Your exercise stamina increases, and you are getting fitter. As a result, your physical activity level shows improvement. You don't feel any energy slump in the afternoon and experience a better mid-day energy level.
You're eating less, but could make healthier choices
This is where a calorie deficit alone isn't a magic formula. Reducing your calories to 1,500 a day but eating processed foods instead of healthy fats, protein and fruit and veg won't give you long-term results. You could also be limiting how healthy you feel overall.