Weight loss appears straightforward, doesn't it? Consume fewer calories, engage in more physical activity, and voilà: The pounds vanish. Regrettably, it's not always that simple. While a low 1200- to 1500-calorie diet suits many individuals, the required calorie count depends on factors such as weight, height, age, gender, and activity level. If exercise depletes a substantial portion of the calories consumed, leaving an insufficient amount to support the body's daily functions—referred to as low energy availability—your body may perceive it as starvation and enter conservation mode.

eat more or less to lose weight

“You don’t want to curtail your diet to the extent that you're left with too few calories to properly fuel your body's functioning,” warns Bronwen Lundy, Ph.D., senior sports dietitian at the Australian Institute of Sport. “You'll risk damaging your metabolism, hindering weight loss, and potentially causing broader effects on your body and health.”

What are these effects, and how can you discern if insufficient calorie intake is responsible for your weight-loss standstill? Read on to discover.

Indications Your Nutritious Habits May Have Affected Your Metabolism Low energy availability is prevalent among female athletes—perhaps you've heard of the female athlete triad, a medical condition characterized by energy deficiency, irregular periods, and low bone density. However, recent research indicates that the issue may be more widespread.

In 2014, experts, representing the International Olympic Committee, recommended replacing the term "female athlete triad" with "relative energy deficiency in sport" to better encompass the complexity of the condition and acknowledge that men are also susceptible. In 2016, researchers from the University of Otago in Dunedin, New Zealand, found that even everyday exercisers might be prone to undereating and affected by the condition. In fact, low energy availability can start negatively impacting the body after just five days of calorie restriction, with more severe complications emerging in the long term.

Identifying whether you have low energy availability can be challenging. The satiating effect of numerous healthy, low-calorie, high-fiber foods—such as fruits and vegetables—coupled with the appetite-suppressing effects of intense workouts, may lead to energy deficiency without apparent hunger. This implies you need to look beyond your appetite.

To determine if you're at risk, first, consider the signs and symptoms of low energy availability. They include:

  • Dizziness
  • Anemia
  • Chronic fatigue
  • Gastrointestinal issues, like cramping, bloating, or constipation
  • Cold sensitivity due to low thyroid hormone
  • Mood changes, such as irritability or depression
  • Recurring infections and illnesses
  • Impaired athletic performance
  • Difficulty gaining or building muscle
  • Elevated cholesterol
  • Frequent injuries, including stress fractures
  • Absent or irregular menstrual cycles
  • Reduced sex drive in men

If you've experienced any of these symptoms, it's advisable to collaborate with a doctor or certified sports dietitian to assess the number of calories your body typically utilizes each day. You can use your BP Doctor app for a rough estimate. Here's how:

  1. From the BP Doctor app dashboard, tap Calories Burned (the flame icon).
  2. Tap the double arrow in the top right corner to expand the screen.
  3. Tap 1wk and then swipe left to see more results.
  4. Note the average number of daily calories burned last week.

Return to the BP Doctor app dashboard and tap the Calories In vs. Out tile (the knife and fork icon). Scroll down to view your average daily calories consumed last week. If you don't log food, consider doing so for at least three days to get a daily average and ensure that your halted weight loss is due to energy deficiency rather than hidden calories in your diet.

Next, subtract the number from step 1 from the number from step 2, like this: [Average Calories Consumed (food) per day] minus [Average Calories Burned per day] = Energy Deficit

Firstly, the calories you're consuming (identified in step 2) should never dip below your basal metabolic rate (the calories your body burns at rest). Secondly, if the gap between what you're eating and the total calories you're burning—simply to exist and through exercise (your "energy deficit," calculated in step 3)—is too large, you risk losing essential muscle tissue and slowing down your metabolism.

“If you’ve been eating too little and exercising a lot and not losing weight, then it’s a sign your efforts are not working and something needs to change,” says Lundy. “The good news is, the impact on your metabolism is unlikely to be permanent. The solution could be that you simply need to slowly start eating more.”

The Healthy Approach to Revitalize Your Metabolism And Achieve Weight Loss Boosting your calorie intake for weight loss may seem counterintuitive—perhaps even daunting. However, to become leaner and stronger, you'll want to reduce body fat while maintaining or building lean muscle. Aim for a calorie target approximately 500 calories less than what you need to maintain your current weight.

“If someone has been following a strict diet for years, it can take longer to restore their metabolism to its full potential,” says Lundy, “but it is possible.” She suggests gradually increasing your food intake by 100 calories a day for two to four weeks—this could be a piece of fruit, a small container of non-fat plain Greek yogurt, or a small handful of nuts (again, food logging can help). Remember, moderation is key:

  • Avoid skipping meals
  • Consume enough protein throughout the day
  • Include ample whole fruits, vegetables, and grains
  • Incorporate low-fat dairy (or soy milk), legumes, and lean meats
  • Properly refuel and rehydrate after intense training sessions
  • Limit sugary beverages, such as sports drinks

If, after stepping on a scale, you observe that your weight isn't increasing, gradually add more calories (in 100-calorie increments) until your body starts shedding fat and maintaining or gaining muscle. (The Aria 2 smart scale can assist in measuring this.) This becomes your sweet spot—the new daily calorie goal to aim for.

Eating more may seem intimidating, but rest assured, not only will your metabolism receive the boost it needs to reignite your weight loss, but your body may also shed more fat while retaining valuable muscle. In the long run, this helps keep you strong and encourages sustained weight management.