It’s that time of year when many people think about weight loss and dieting. The weather is warming up, end of year festivities are planned and the gym is bustling as the summer vibe is in the air.

But alas, you’ve noticed some weight gain from winter hibernation. Maybe you’re thinking of reducing the carbs, increasing your exercise or eating fewer calories. Better yet, why don’t you try a crash diet that claims you’ll be looking fabulous in your new swimwear in as little as 6 weeks?

Well, there is a good reason you should definitely reconsider jumping on a drastic crash diet plan. While you might see some weight loss initially, more often than not, it will result in weight gain long-term and lead you with poor metabolic health. These extreme low-calorie diets can also have a detrimental impact on your mental wellbeing.

Here are just some of the things you can expect when undergoing a “lose weight fast” crash diet:

1. Your body burns glycogen

In the first day or two of a crash diet, your body enters starvation mode and begins to utilise the stored glycogen for energy. Glycogen is a form of carbohydrate that’s stored in your muscles and liver.

When you reduce your calorie intake, you start to burn the glycogen for energy, not body fat. As water is attached to the glycogen molecules, you also start to lose water weight giving you the false impression your crash diet is resulting in immediate fat loss.

2. Your cortisol levels may rise

Your cortisol levels rise due to the stress you are inflicting on your body. The hormone corticosterone is released which may result in you feeling irritability and agitated. It’s not uncommon during this time to experience symptoms of depression, disturbed sleep and poor concentration. These symptoms may be exacerbated by blood sugar dysregulation, particularly if you’re following a very low-carb or low-calorie eating plan.

3. Your metabolic rate will slow

In as little as 48 hours of starting a crash diet, your body’s metabolic rate can slow in order to conserve your energy. The reduced number of calories means the body’s energy stores are virtually depleted and it adapts to this starvation environment.

The lowered metabolic rate can cause you to feel tired and unmotivated. While this survival instinct can come in handy when food is scarce, it can actually cause the body to store fat and increase in body weight long term.

4. Your muscle mass will reduce

When your metabolism slows, your body burns fewer calories and its choosing to store body fat as this offers more sustained energy. One of the side effects of extreme dieting is that you’ll experience lean muscle breakdown. This might look like you’ve achieved substantial weight loss through burning fat but you’ll be losing valuable muscle. Less muscle causes your metabolic rate to slow further.

5. You may feel fatigued

The reduction in nutrients of your crash diet meal plan will end up making you feel fatigued. Extreme dieting can also affect your thyroid function making you feel lethargic and the reduction in your glycogen stores and water also impacts your energy.

6. Your bowel habits may become irregular

A poorly balanced diet can lead to changes in your bowel habits. This may not seem like a problem in the short-term, but long-term irregular or inconsistent bowel movements can play havoc with your overall health including disrupting your gut microbiome and the reabsorption of toxins.

7. Your skin and hair quality can be damaged

If you’re opting for rapid weight loss to help improve your physical appearance, you may want to keep in mind the effect crash dieting has on your skin and hair. The lack of vitamins and minerals, restriction on healthy fats and limited variety across all food groups compromise the natural lustre of your hair and the quality of your skin. Breakouts are common and dryness can occur leaving you looking unrefreshed and unhealthy.

8. You may experience dehydration

Feeling dizzy? Have a headache? Rapid weight loss is often associated with dehydration causing unpleasant side effects like these. Unfortunately, when you lose weight quickly on a fad diet such as a juice cleanse, you’re really losing water weight. This increases the risk of dehydration and while that can be fixed by increasing your water intake, when you start eating solid foods or a balanced diet the weight gain tends to follow.

What’s better than crash diets? Getting a diet plan through a dietitian or nutritionist that can help you achieve your personal goals. That might be the keto diet, low-carb or even intermittent fasting. Whatever it is, the diet plan will be tailored to your our body type and lifestyle, helping you to reach your goal weight sustainably.