What Do You Eat on an OMAD (One Meal a Day) Fasting Diet and What Happens to Your Body?

OMAD is a type of intermittent fasting diet in which all the calories your body requires per day are consumed in a single meal or within a 1 to 2-hour window. You eat a 1,200 to 1,500 calorie dish including all major food groups and it improves your metabolism along with providing other benefits.

Eating healthy, losing weight, and staying fit are many people's goals. If you’ve been on the lookout for a diet to help you achieve your health targets or are simply looking for a lifestyle change, intermittent fasting has been quite popular recently. 

Intermittent fasting mainly involves restricting the time periods when you eat. For example, in the 16:8 diet, you can eat at any time for 8 hours in the day but have to fast for the remaining hours. Another type is the 5:2 fast, in which you eat normally for 5 days a week but then fast for the remaining 2 days.

The latest type of intermittent fasting diet is called one meal a day (OMAD). Read on to find out how the OMAD fasting diet works. 

OMAD is a type of intermittent fasting diet in which all the calories your body requires per day are consumed in a single meal or within a 1 to 2-hour window. You’re expected to fast for the remaining hours of the day until the next meal.

For OMAD to work well, eating at the same time of the day is recommended. So, you have to be consistent in which meal you choose to eat every day. For example, if you’re a morning person, you may want to eat a hearty breakfast once you wake up. But if you’re a night owl, a late lunch or an early dinner might be more suitable for your lifestyle. 

Another aspect of successfully managing OMAD is to consume an adequate number of calories within a single meal. Food provides nutrition and energy for your body to function normally. Eating OMAD doesn’t mean deprivation as this can lead to health issues like chronic fatigue, hormonal imbalance, and poor immunity. 

If you don’t eat enough calories relative to the amount you burn, your body will conserve energy, thus preventing you from losing any weight.

So, if you decide to try the OMAD diet, ensure that you’re eating enough to support the caloric requirements of your body. It’s expected that you might need an adjustment period to help your body adapt to receiving all its nutrition in a single setting. Eventually, your body will become used to eating just one calorie-dense meal a day.

OMAD diets are likely to put your body in an acceptable calorie deficit. This means that you’re likely to burn more calories than you consume. This is the most conducive environment for the body to use up the stored fat in the body, leading to weight loss.

The body breaks down the food we eat into its component sugars like glucose for use as energy. This is done by a hormone called insulin, which manages the blood sugar levels in the body. If there are any extra sugars, they get stored as fat in the body. When you don’t eat for long periods of time, like in the OMAD diet, there are no sugars to break down. This causes a drop in your insulin levels. The stored energy in the fat cells then begins to be used. 

Compared with short fasting windows, overnight fasting has been shown to result in decreased body weight. Eating 1 or 2 meals a day has also been associated with an annual reduction in body mass index values.

Besides weight loss, the OMAD diet has been associated with many other health benefits. These include:

1. Fasting improves your metabolism.
2. Fasting promotes alertness because when you fast during the daytime, your body produces a chemical called orexin-A. This chemical is responsible for wakefulness. So increased orexin-A levels in your body can make you feel more alert.
3. Fasting has been shown to decrease the levels of inflammatory biomarkers like C-reactive protein and leptin. This indicates a reduced risk of developing inflammatory diseases such as chronic infections or cardiovascular diseases like atherosclerosis. 
4. Intermittent fasting can lower blood pressure levels in people with hypertension.
5. Intermittent fasting has been documented to lower your insulin and fasting blood sugar levels.
6. Fasting can help in reducing certain risk factors for heart disease such as bad cholesterol levels.
7. Fasting can also provide benefits to your nervous system. It may enhance longevity and slow down the degeneration of the brain tissues.

However, most of these benefits have been linked to intermittent fasting regimens in general and not only to the OMAD diet. In fact, extreme calorie restrictions could be harmful to the body.

Excessive calorie restriction has been associated with increased bad cholesterol and fasting blood sugar levels. You could also experience extreme and constant hunger due to the rise in hunger hormone levels.

Other potential side effects include fatigue, nausea, dizziness, constipation, and irritability. 

So OMAD may not be suitable for everyone, especially people with special nutritional requirements like children and adolescents, older adults with comorbidities, people with eating disorders, and pregnant or breastfeeding women.

Other considerations include people taking other regular medications. As you’re only eating once a day, food-dependent medications such as aspirin or steroids may not be absorbed well and result in ineffectiveness or increased side effects of medications.

If you’re diabetic, the sudden spikes or falls in glucose levels with prolonged fasting could also be detrimental to your health.

If you have stomach issues like bloating, acidity, or constipation, prolonged fasting could aggravate your condition. So OMAD might not be a good fit for you.

OMAD may also impact your social life and make it difficult to resist temptation and stick to your diet. Eating can be challenging during special occasions like birthdays, parties, and festivals.

However, OMAD is completely and doable if planned well and carried out responsibly.

An OMAD diet requires careful planning because adequate calories and essential nutrients have to be packed into a single meal to avoid deficiencies. 

OMAD diet meals usually deliver around 1,200 to 1,500 calories and include all major food groups like carbohydrates, proteins, and fats. Here are some sample meal plans:

• An egg dish like an egg white omelet or scrambled eggs with sides like avocado, goat cheese, baked potato fries, or wedges and grilled vegetables in olive oil, accompanied by fruits dipped in dark chocolate and topped with whipped cream.
• A chicken dish that's either baked or grilled with sides like mashed potatoes, roasted broccoli or cauliflower with olive oil, accompanied by a fruit smoothie with honey or Greek yogurt topped with trail mix, berries, or nuts.
• A fish dish like grilled salmon with sides like guacamole, a salad, or brown rice, accompanied by a fruit bowl garnished with coconut flakes, nuts, and flaxseed.

OMAD can be challenging and might not be recommended for all seven days a week. You could try OMAD for a few days and then eat normally for the rest of the week or alternate OMAD and normal eating days of the week, whichever works for you. The idea is to not feel hungry and be just as active and energetic while eating much lesser than usual.

Because you’ll be eating only once in a day, try to consume the five main food groups with healthy fats, which are considered the building blocks of nutrition. These are:

1. Fruits

These include both whole fruits and fruit juices.

2. Vegetables

These include green, leafy vegetables like broccoli and spinach, red and orange carotene-rich vegetables like carrots and tomatoes, starchy vegetables like potatoes, beans, peas, and other vegetables like mushrooms and squash.

3. Grains

These include whole grains like brown rice, popcorn, and oatmeal and refined grains like muffins and pasta.

4. Protein foods

These include meats like chicken and turkey, seafood, nuts, soy, and seeds.

5. Dairy

These include milk, yogurt, cheese, and kefir.

What to avoid

Avoid processed foods like sugary baked goods, chips, and soda, as they have very poor nutritional value and don’t make you feel full for too long. This can make it difficult to maintain OMAD, as you’re likely to feel hungry very soon.

Processed foods can also make you gain weight, as you tend to overeat them. These foods are also associated with an increased risk of disease.

OMAD can also get a little more challenging and may require greater customization if combined with other diet regimens like veganism or a low-fat diet.

You may be fond of nibbling on food at all times of the day, but this may not be good for your health.

Intermittent fasting is slowly turning out to be a more effective way to achieve and maintain your health goals. The OMAD diet is becoming increasingly popular among the various intermittent fasting regimens. 

Besides weight loss, there are many documented health benefits of prolonged fasting.

OMAD is a more extreme version of intermittent fasting. But if done right, it's proven to be an effective technique for not only losing weight but also maintaining stable physical and mental health while eating less.

As with all things, caution is necessary. Because OMAD can involve drastic lifestyle changes, an adjustment period is critical to successfully maintaining this diet.

Finally, there is no “one right answer” for everyone looking to discipline their eating habits or incorporate a fasting regimen into their diet. Making an informed decision based on adequate research and seeking professional consultation if required is important for a safe and healthy lifestyle.