The Effects Of Crash Diets On The Brain

The Effects Of Crash Diets On The Brain

“Crash diets increase the level of the stress hormone called corticosterone which makes the brain more susceptible to stress”

Crash Diets And Its Effects

Crash diets are typically very low in calories and tat, which lead to rapid weight loss in a short span of time (within a few days). The motives behind this desire for rapid weight loss are often cosmetic rather than health-related. The reasons could include trying to look good for an upcoming wedding, party, date, etc, Additionally, some people opt for crash diets with the erroneous belief that rapid weight loss by whatever means, would lead to a better health status.

Crash diets may help an individual to reduce body weight in a short period of time. However, in the long run, the weight would come back (to the original weight) or it may increase in some cases and this is because, people may eat more after the crash diet period has ended, after the purpose of looking good on a specific occasion has been achieved. Also, the metabolic rate decreases during the period of a crash diet (as the body tries to adjust to a low caloric intake) and the metabolic rate may not increase, even when normal food intake is resumed, later on.

Crash diets may have several harmful effects on the health and this could include feeling weak, tired and fatigued. There may be muscle weakness, lethargy, deficiency of essential vitamins and minerals. The brain too, is affected, so shared here are some of the adverse effects of crash dieting on the brain.

How Crash Dieting Affects The Brain

Impaired Memory And Concentration

The brain needs carbohydrates (glucose) to function well. If the carbohydrate intake is reduced (to less than 100 grams per day) there is a shortage of glucose for the brain.

The body copes by breaking the fatty acids to ketones, which try to do the job of carbohydrates. The brain, however, cannot function well with ketones, resulting in impaired attention, concentration and memory. The impairment of memory can become long lasting too. Reaction time is also slowed, for those on crash diets.

Increased Risk Of Depression And Stress

Crash diets increase the level of the stress hormone called corlicosterone, which makes the brain more susceptible to stress.This increases the risk of depression. Another factor leading to depression in people with crash diets is lower levels of serotonin. This is because the amino acid tryptophan, the precursor of serotonin is less in crash diets (diets providing less than 1000 calories per day).

Low Sodium Levels

Crash diets are low in salt content. This leads to a deficiency of sodium (a condition, also referred to as hyponatremia). Sodium is extremely important for vital brain functions such as maintaining alertness and concentration. Those with hyponatremia may appear confused and disoriented. In severe cases, it may lead to drowsiness and a comatose state too.

Low Potassium Levels

Crash diets can also lead to low potassium levels in the body, a condition referred to as hypokalemia. Potassium is required for the proper functioning of muscles and the lack of potassium leads to muscle weakness and lethargy.

Increased Risk Of Brain Stroke

Crash diets, especially if repeatedly done, causes the shrinking of blood vessels, leading to atherosclerosis. This leads to reduced blood supply to the brain, leading to brain stroke, which may cause paralysis or loss of speech.


Crash diets are nothing but food fads. They are unscientific and are associated with multiple harmful effects on brain health. So those opting to lose weight, should not rely on crash diets but instead, should adopt these proven methods to lose weight in a scientific manner:

  • Aim for about 0.5-one kilo weight loss per week, and not more than that
  • Reduce the intake of saturated fat and sugars/carbohydrates in the diet
  • Increase the intake of proteins such as lean meat, fish, etc.
  • Increase the intake of fruits, vegetables and whole grains

How To Eat Healthy

Getting on with a healthy diet isn’t easy, but here are a few tips to stay on track and to build healthy eating patterns:

  • Keep yourself well hydrated as it helps in reducing cravings and keeps you feeling full
  • Never miss your meals and try eating at the same time every day
  • Get active. Increasing your activity level a notch, helps you create a mindset to eat healthy too
  • Plan in advance the food to munch on, when hunger pangs or cravings are bound to strike
  • Have a healthy alternative in place to deal with the cravings
  • It’s okay to slip up now and then, so forgive yourself for the same.

Health Tip

Small changes are the ones that set you in the right direction and help you improve your life

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