Brief Answer:
Intermittent fasting is a new diet plan, so far it is found effective and generally safe

Detailed Answer:
Hello and welcome to 'Ask A Doctor' service,

Intermittent fasting is a new dieting method and there are not yet many studies to definitely define the potential side effects. By what is noticed so far in studies, this method of dieting is quite effective and is generally safe.

Intermittent fasting has recently gained interest over continuous fasting due to these advantages: no increase in hunger, it boosts the metabolism rate at rest (increases weight loss), less tiredness or fatigue, more effective than continuous dieting (in continuous fasting the body adapts soon to the new calory intake and stops losing weight).

As for disadvantages with intermittent fasting, studies have shown that those who use this method of dieting may have headaches, constipation, lightheadedness, irritability during fast days and few studies have even shown a dropout rate of up to 65%

Also, intermittent fasting may not be good for people that need to have regular meals such as in pregnant or breastfeeding women, diabetes, elderly, patients with eating disorders or if they need to take medications with food regularly (chronic conditions)

The most recognized and studied intermittent fasting are 5:2 and alternate day fasting (ADF) and generally, it is safely used in overweight people and those with a normal weight that would like to lose some more weight.

It is important to combine intermittent fasting with exercise as this is superior to fasting or exercise alone. Furthermore, if intermittent fasting is used for a long time, its effect in weight loss plateaus in 6 months, so continuing exercise increases the chance of continuing to lose weight or keep the desired weight.

I hope this answers your query.
I remain at your disposal in case further medical assistance is needed.

Kind regards,
Dr. Antoneta Zotaj,
General and Family Physician

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