OMAD diet or One Meal a Day diet is a type of extreme time-restricted intermittent diet regimen where a person fasts for 23 hours of the day and has an eating window of only one hour. The whole idea about it is to limit calorie consumption throughout the day. 

Although many dieters have preached about the effectiveness of the typical 16:8 intermittent fasting (16 hours fasting, 8-hour eating window) on losing weight, the OMAD diet is not recommended by experts as the risks may outweigh its benefits. Below are the facts that you need to be aware of before trying the diet. 

OMAD only allows a 1-hour eating window throughout the day

Can the OMAD diet make you lose weight?

The more popular and less extreme types of intermittent diet that allow a longer eating window (4-8 hours) have been observed to increase insulin sensitivity, improve glucose tolerance, and also helped people lose weight in just a matter of weeks. These versions of intermittent fasting are considered good alternatives to daily caloric restriction for people who are keen on improving their body composition and overall health.  

On the other hand, a study published in 2015 by the Journal Nutrition Reviews warns us against the harmful effects of extreme versions of intermittent fasting like the OMAD diet. The findings of the study suggested that eating one meal a day may lead to an abnormal boost in appetite that can result in a higher body fat percentage to the dieter.

This is because people tend to overeat during the eating window and consume ungodly amounts of calories. The overeating then leads to a surge of insulin in the body making you feel sick and lethargic all throughout the day. 

People tend to overeat during the eating window

Is the OMAD diet healthy?

The main idea behind this diet is to allow your digestive hormones, metabolic functions, and your vital organs to rest or take a break. Researchers believe that fasting improves the function of your organs and also reduces susceptibility to insulin resistance which can lower the risks of diabetes. 

However, there are also numerous pieces of scientific evidence suggesting that as soon as you break the diet, the appetite-suppressing hormones rapidly halts its function and make you feel hungrier than when you started. This is the complete exact opposite of what you want to happen when dieting.

What are the side effects of eating only one meal a day?

The side effects of restricting food for 23 hours can include: fatigue, difficulty concentrating, irritability, nausea, lightheadedness, destabilized blood pressure, hypoglycemia or low blood pressure, increase in body fat, and muscle loss.

 These side effects can pose significant problems in carrying out your day. Without the proper fuel, it will be hard to exercise, you will have less concentration at work, and you could miss out on important personal occasions. 

Having no food consumption for 23 hours can have negative side effects on your body

Can everyone try the OMAD diet?

The OMAD diet can be dangerous to children, the elderly, and people with pre-existing medical conditions such as diabetes. Regular intake of calories is necessary to maintain proper health for these groups. Another group who should not subscribe or even attempt to try this type of diet are people who regularly take prescription drugs, as the majority of medications require food before taking them. 

The bottom line

If you still wish to try the OMAD diet, opt for a wide variety of nutrient-packed whole foods such as fruits, vegetables, nuts, whole grains, and lean cuts of meat. Remember that there is very little research that determines whether the diet is safe, sustainable, and effective for weight loss.

If you are interested in fasting to lose weight and optimize the other benefits of fasting, try the other less extreme types of intermittent fasting. However, always consult a nutritionist or a doctor before trying any restrictive forms of fasting especially if you have an underlying medical condition.