In the quest for weight loss, many people fall into the trap of drastically cutting calories, aka crash dieting. Although it might seem like an effective way of fast-tracking your weight loss results, the reality isn’t all that simple, as consuming too few calories can actually have adverse long-term effects on your metabolism (and overall health). Let us explain.
The dangers of crash dieting
Crash dieting involves a significant reduction in caloric intake, often by skipping meals or eliminating entire food groups. Although initially, this method can lead to quick weight loss, these results are often short-lived.
Why? Well, your body sees severe calorie restrictions as a threat, triggering what is known as starvation mode, which slows down your metabolism to conserve energy – making it harder and harder to maintain your weight loss.
And it doesn’t end there. The long-term consequences can be detrimental to your health, potentially leading to:
- Nutrient deficiencies: A lack of essential vitamins and minerals can lead to a weakened immune system and increase the risk of health issues.
- Loss of muscle mass: When you don’t eat enough, your body may start burning muscle for energy, reducing lean muscle mass and further slowing metabolism.
- Delayed weight gain: Once normal eating patterns resume, the body tends to store fat more efficiently to prepare for potential future caloric deficits, often resulting in regaining the lost weight – and then some.
- Lowered thermic effect feeding (TEF): Eating fewer calories means your body uses less energy to digest food, so you’re not burning as many calories as usual.
- Hormonal changes: Prolonged calorie restriction can decrease levels of thyroid hormones and leptin (the hunger hormone), slowing down your metabolism and increasing your hunger levels.
How to recognise undernutrition
Here’s the good news: your body will send you signals when it’s not receiving adequate nutrition, so you can take steps towards better eating habits (and better health). Here’s what to keep an eye out for:
- A constant feeling of tiredness can indicate insufficient energy intake.
- Dizziness, sweating, and feeling cold even in warm environments.
- Irritability and frequent mood changes
- Constantly thinking about meals and experiencing “food noise”
- Hair loss and skin issues (these could be signs of a nutrient deficiency)
- A weakened immune system, which can lead you to get sick more often and take longer to recover
Avoiding a metabolic slowdown
Achieving your weight loss goal while avoiding a metabolic slowdown is all about finding a balance when reducing calories. Here are some tips to prevent your metabolism from slowing down:
- Avoid drastic calorie cuts: A moderate calorie deficit of 500-700 calories per day is often recommended.
- Prioritise protein: Protein helps you maintain muscle mass as you lose weight, which is crucial for keeping your metabolism high.
- Start strength training: Building and preserving muscle through resistance training will keep your BMR higher, as muscle tissue burns more calories.
- Use refeed days: Periodically increasing your caloric intake can help prevent long-term metabolic adaptation and keep your hormones balanced.
- Get enough sleep: Poor sleep can negatively impact your metabolism and hormones, leading to further weight loss challenges.
Additionally, Registered Nutritionist and Health Coach at Juniper, Lani Finau recommends:
“To get a better understanding of your food intake, often it can be helpful to track your meals, snacks and drinks for 1-2 days to get a baseline understanding of your energy and macronutrient intake – compared to your requirements.
“From there, you can tweak the meals as needed! In addition to this, establishing a regular eating pattern of 3 balanced meals and 1-2 protein and fibre-rich planned snacks daily can help stabilise appetite and cravings across the day.”
“We recommend aiming for at least 2-3 litres of water per day – as well as ensuring you replace lost fluids through sweat if exercising! Some quick tips to help increase your water intake; set alarms/reminders on your phone every couple of hours to drink a glass of water, grab yourself a water bottle that has time stamps on it, or even try incorporating more herbal teas,” she adds.