The OMAD diet, short for One Meal A Day, is an extreme intermittent fasting plan that has grown increasingly popular for weight loss. As the name suggests, it involves eating just one meal daily within a restricted time period.
But is limiting your food intake to only one meal healthy or effective? Let’s take a closer look at what the OMAD diet is, its proposed benefits, and potential side effects.
What Is The OMAD Diet?
This fad diet requires you to fast for 23 hours straight, eating all your calories in just one hour every day. Most people choose to eat their single daily meal at dinnertime. During the fast, you can consume low-calorie drinks like water, unsweetened tea, or black coffee.
The OMAD diet is an extreme form of intermittent fasting, as most IF plans allow a larger 4-8 hour eating window. But OMAD takes this to the extreme by squeezing all meals into one hour. Proponents claim restricting calories severely turbocharges weight and fat loss.
Benefits Of The OMAD Diet
Below are some of the touted health and weight loss benefits of the OMAD diet:
✅ Weight Loss
By severely limiting calories, the OMAD diet often creates an extreme daily calorie deficit. This forces your body to burn through glycogen stores and tap into fat stores for energy. Eating one meal may better control hunger hormones as well. These factors typically result in accelerated weight loss at first.
✅ Reduced Insulin Resistance
Going extended periods without food may improve insulin sensitivity, according to some studies. Lowering insulin resistance helps stabilize blood sugar levels and reduces fat storage over time.
✅ Increased Growth Hormone
Fasting for longer periods of time increases human growth hormone production. Higher GH levels are associated with more lean muscle mass and expedited fat burning. However, extreme calorie restriction tends to undercut muscle gains.
Fasting for longer spurts promotes a process called autophagy, where old cells die off and are replaced by new cells. This regenerative effect keeps tissues and organs functioning optimally longer. It may lower the risks of cancers and neurodegenerative diseases.
The OMAD diet requires very little meal prep or planning. You get to enjoy one large meal with favorite foods, without worrying about additional meals throughout the day. This makes it easier to follow than most diets. Just one hour of eating means less time spent cooking and cleaning too.
Potential OMAD Diet Side Effects
Despite some benefits, the OMAD diet does come with the following risks and drawbacks:
- Nutrient deficiencies – It’s extremely difficult to fit all necessary macro- and micronutrients into one meal daily. Missing nutrients over time can cause many health problems.
- Increased disordered eating – For those prone to eating disorders, restrictive fad diets with long fasting periods reinforce unhealthy behaviors and obsessive calorie counting.
- Binge eating – After fasting for 23 hours straight, people tend to binge and lose control when their eating window finally opens. Eating too fast leads to poor digestion as well.
- Decreased metabolism – Prolonged periods with inadequate calories can lower your metabolic rate as the body tries to conserve energy. This makes long-term weight maintenance very difficult.
- Poor sleep – Going to bed on an empty stomach makes falling and staying asleep much harder for most people. Poor sleep tends to disrupt appetite hormones.
- Lack of energy – It’s tough to power through daily activities and workouts with no/low fuel intake for 23 hours. Headaches, dizziness, and brain fog are common side effects.
The OMAD diet promotes accelerated short-term weight loss by squeezing all calories into just one meal daily. However, adopting this extreme form of intermittent fasting long-term may cause more harm than good for overall health. Nutrient deficiencies, disordered eating patterns, lack of energy, and rebound weight gain are common problems.
More moderate intermittent fasting plans that allow 4-8 hour eating windows are likely safer and easier to sustain. Pairing IF with a balanced diet and exercise gives you the benefits of fasting while avoiding the downsides of prolonged nutrient restriction seen in the OMAD diet.
A: Most people need around 1,200-2,000 calories in their one meal. Calculate your calorie needs based on age, gender, and activity level.
A: Focus on satiating foods with healthy fats, quality carbs, and lean proteins. Avoid heavily processed foods or sugar spikes.
A: Most find success eating later, like 2-3 PM or 5-6 PM, to better distribute fasting periods. But listen to your hunger cues.
A: Yes, but reduce intensity and watch for low energy. Fuel appropriately after workouts. Light exercise is ideal for fast days.
A: No, restricting calories this severely on a regular basis can lead to health issues over time due to lack of nutrients. Use it only short-term.