One Meal A Day (OMAD) is a form of intermittent fasting that has gained popularity for its simplicity and prospect of significant health benefits.

Unlike traditional eating patterns which typically involve 3 meals a day, OMAD involves eating all of your daily calories in a single meal.

By doing this, you restrict food intake to a very short window of approximately 1 hour each day.

This is an extreme version of intermittent fasting, grounded in the belief that prolonged periods without food can lead to improved health outcomes and weight management.

How OMAD works

The concept of OMAD is quite straightforward: eat once and then fast until the next day’s mealtime.

This approach is not just about limiting food intake to one meal a day.

It is also key to adhere to the same eating window daily to stabilise the body’s internal clock.

Flexibility in choosing the mealtime allows individuals to align their eating window with their lifestyle, making it a theoretically accessible approach to weight management and health improvement.

Advantages of OMAD

As with any eating approach, there are a range of potential advantages and disadvantages.

Potential for weight loss

OMAD’s restriction to a single daily meal can naturally lead to a reduction in calorie intake, thereby facilitating weight loss.

This aspect of OMAD can be particularly beneficial for weight management.

However, it’s important to acknowledge that OMAD may not suit everyone and that individual experiences can vary.

Limited research suggests that intermittent fasting can improve insulin sensitivity, thereby potentially aiding in blood sugar regulation.

Save time

Planning and preparing one meal a day is simpler and less time-consuming than traditional diets.



The strict nature of OMAD makes it challenging for many to sustain long-term. Some people may find this approach leads to increased hunger.

Nutritional deficiency risks

With only one meal to provide daily nutrients, there’s a heightened risk of deficiencies.

Potential for binge eating

The restriction can lead to overeating during the eating window, negating some of the diet’s benefits.

Potential blood glucose fluctuations

For people with diabetes, OMAD poses potential risks including significant blood sugar fluctuations.

Lack of food intake for extended periods may lead to hypoglycemia (low blood sugar) while the consumption of a day’s worth of calories in one meal might cause hyperglycemia (high blood sugar).

Therefore, individuals with diabetes considering OMAD should do so under medical supervision.


While studies on intermittent fasting show promise for weight loss and improved metabolic health, research specifically targeting OMAD is less abundant.

Some evidence suggests potential benefits in weight management and insulin sensitivity, which are critical for people with diabetes.

Nevertheless, the research is ongoing, and current findings should not be seen as conclusive.

While OMAD presents a simplistic and potentially effective approach to dieting, it requires careful consideration and is not universally suitable.

The diet’s extreme nature means it may offer benefits for some, particularly in terms of weight loss and metabolic health.

However, it also carries risks. Speak to your doctor before adopting this dietary approach.

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