9 Things That Can Happen To Your Body When You Crash Diet

According to a doctor.
PHOTO: Getty Images

Crash dieting is unfortunately pretty common. "A crash diet may help you lose those extra pounds in time for that week [at the beach], [but] the results are generally short-lived and can ultimately have a negative impact on your body and mind," says Dr. Julianne Barry, General Practitioner at London Doctors Clinic.

Here, Barry lays out exactly how crash dieting can impact your body:

  1. It can reduce your metabolic rate.

    A high metabolism is key to losing weight, but crash dieting can actually make your metabolic rate lower. "Muscle breakdown is much greater with extreme dieting, rather than a steady prolonged approach. Less muscle reduces your metabolic rate, which is the number of calories you burn while resting and can ultimately result in weight gain later on," explains the doctor.

  2. It can weaken your immune system.

    "By depriving yourself of essential minerals and vitamins you risk weakening your immune system," says Dr. Julianne. And we all know that a low immune system makes getting ill far more likelynot what you want while you're away on holiday. "If you cut out all fatty foods from your diet, absorbing fat-soluble vitamins such as A, D, E and K may prove problematic," the doctor explains. "These vitamins are necessary as they help to support your immune system, so a lack of them could cause future issues."

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  3. It can cause ketone production.

    "With a very low carbohydrate diet, your body may start to break down fatty acids to produce ketones," says Dr. Julianne. You might have heard of ketones if you've ever read up on the keto diet. Sure, it might cause you to drop a few pounds, but it's also got some damaging side effects too, including "nausea, bad breath and liver or kidney problems."

  4. It can cause dehydration.

    Have you ever wondered why some diets, like juicing, lead to such quick weight loss? It's because you're losing water weightbut that's not ideal for longer-term weight loss. "Glycogen stores, which are a source of energy that binds water, are depleted faster than the fat cells releasing the water. So, when you start eating again, your body will replenish glycogen and water stores and weight gain follows," Dr. Julianne explains. "You run the risk of dehydration as a result, which can manifest with a headache and dizziness."

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  5. It can trigger heart issues.

    "Crash dieting can have some positive outcomes, for example, lowering blood pressure, cholesterol, and blood sugar levels," notes the doctor. But they can also have some potentially harmful effects on the heart as a result of increased heart fat levels, which can occur. "Anyone with heart problems should discuss this with their doctor prior to embarking on a crash diet due to the risk of heart problems arising early on in the diet," she adds.

  6. It can damage your hair and skin quality.

    If vanity's your thing, this might convince you to avoid crash dieting. "When you go on a crash diet, you limit the amount of vital vitamins and nutrients that your body absorbs," explains Dr. Julianne. And this, in turn, may have a negative impact on your physical appearance. "The lack of nourishment may be reflected in your hair, causing it to look lackluster, fall out, and generally reflect your lack of the right vitamins. Similarly, your skin could be left feeling dry and you may experience an acne breakout," adds the GP.

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  7. It can disturb bowel habits.

    A crash diet can also result in some tummy trouble. As the expert explains, "if you are not getting the right nutrients in your diet, this could result in irregular or inconsistent bowel movements." Dr. Julianne advises taking note of the consistency of your stool to work out whether your diet is healthy. "If it is either too runny or very difficult to pass, it is a sign that you should make a dietary change," says the GP, adding: "If you are worried be sure to contact your GP."

  8. It can leave you with low energy levels.

    "While crash diets may lead to weight loss, most of this weight comes from the reduction of glycogen and water in the body, which can result in the loss of energy, making you feel fatigued," says the doctor. "Similarly, due to the reduction of vitamins and nutrients taken in while doing a crash diet, your body is unable to produce energy, leaving you feeling sluggish and tired."

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  9. It can make you irritable.

    Don't want to be a grump on holiday? Crash dieting might not be the way forward. Barry explains how fad diets "can trigger the release of corticosterone from the brain, which predisposes us to heightened stress levels, irritability, and risk of depression. You may also experience poor concentration and disturbed sleep which can lead to fatigue," she adds.

An alternative to crash diets

"Rather than putting yourself under the pressure and perils of a crash diet," Dr. Julianne advises, "try to give yourself more time with regular realistic weight loss goals."

With longer-term lifestyle changes, you will be more likely to make a long-term difference of a more toned and healthy physique, while avoiding the turmoil of depriving yourself of a nutritious and balanced diet.

Here are 11 little things the GP advises you can do instead of crash dieting to improve your health:

  1. Reduce alcohol intake.
  2. Reduce intake of sugary foods and less processed foods.
  3. Include more lean protein in your diet.
  4. Aim for a diet rich in fruit and vegetables and nuts, legumes, and whole grains.
  5. Reduce stress levels.
  6. Avoid foods that contain trans fats, but do go for healthy fats!
  7. Increase dietary soluble fiber.
  8. Maintain a regular level of physical activity to keep your metabolic rate higher.
  9. Try to find a form of exercise you enjoy and make an effort to fit it into your daily routine. 
  10. Do 150 minutes of moderately intense exercise per week.
  11. Try to achieve 10,000 steps per day.
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This article originally appeared on Cosmopolitan.com/uk. Minor edits have been made by the Cosmo.ph editors.

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